BAPI Programming

HELP.CABFABAPIREF

BAPI Programming

Release 4.6B

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BAPI Programming

SAP AG

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Meaning Caution Example Note Recommendation Syntax Tip

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Contents BAPI Programming .............................................................................................6 BAPI Programming Guide............................................................................................................. 7 BAPIs .............................................................................................................................................. 9 BOR ............................................................................................................................................... 11 Terminology ................................................................................................................................. 13 Further Documentation on BAPIs.............................................................................................. 14 Defining and Implementing the BAPI ........................................................................................ 15 BAPI Explorer............................................................................................................................... 17 Working with Display Functions ............................................................................................... 18 Working with Tools and Projects .............................................................................................. 20 Defining the Scenario.................................................................................................................. 21 Reviewing the Scenario Concept ............................................................................................... 23 Defining a BAPI and Its Interface ............................................................................................... 24 Standardized BAPIs ................................................................................................................. 26 Standardized Parameters......................................................................................................... 29 Determining the Object Type and Its Key Fields ...................................................................... 31 Defining the Interface Structure of the BAPI ............................................................................ 32 Naming Parameters in the Function Module ............................................................................ 34 Defining Data Formats.............................................................................................................. 36 Specifying Development Objects in ABAP Dictionary.............................................................. 37 Naming the Method in the BOR ............................................................................................... 40 Naming Parameters in the BOR............................................................................................... 41 Naming the Function Module and the Function Module Group................................................ 43 BAPIs Used for Outbound Processing ..................................................................................... 45 Creating Development Objects and Documentation ............................................................... 46 BAPI Interface and Function Module......................................................................................... 48 Testing the BAPI and Its Documentation .................................................................................. 52 Releasing the BAPI...................................................................................................................... 53 General Programming Guidelines for BAPIs ............................................................................ 54 Transaction Model for Developing BAPIs ................................................................................. 58 BAPI Transaction Model with Commit...................................................................................... 60 BAPI Transaction Model Without Commit ................................................................................ 63 Customer Enhancement Concept for BAPIs ............................................................................ 65 Internal and External Data Formats ........................................................................................... 69 Providing Input Help (F4 Help) ................................................................................................... 73 Providing Interface Descriptions ............................................................................................... 75 Buffering with Write BAPIs ......................................................................................................... 77 Example of Implementation and Process Flow ........................................................................ 83 Improving Performance .............................................................................................................. 86 Documentation Guidelines ......................................................................................................... 88 Programming Standardized BAPIs ............................................................................................ 90 Programming GetList() BAPIs .................................................................................................... 91 Example of a GetList() BAPI..................................................................................................... 92 Programming GetDetail() BAPIs ................................................................................................ 93

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Example of a GetDetail() BAPI................................................................................................. 94 Programming GetStatus() BAPIs ............................................................................................... 96 Example of a GetStatus() BAPI................................................................................................ 97 Programming ExistenceCheck() BAPIs..................................................................................... 98 Example of an ExistenceCheck() BAPI .................................................................................. 100 Programming Create() BAPIs ................................................................................................... 102 Example of a Create() BAPI ................................................................................................... 104 Programming Change() BAPIs ................................................................................................. 106 Example of a Change () BAPI ................................................................................................ 108 Programming Delete() BAPIs.................................................................................................... 110 Example of a Delete() BAPI.................................................................................................... 112 Programming Cancel() BAPIs................................................................................................... 113 Example of a Cancel() BAPI................................................................................................... 114 Programming Replicate()/SaveReplica() BAPIs...................................................................... 115 Example of a SaveReplica() BAPI.......................................................................................... 118 Programming Methods for Sub-Objects ................................................................................. 120 Programming Standardized Parameters ................................................................................. 122 Address Parameters.................................................................................................................. 123 Change Parameters ................................................................................................................... 125 Extension Parameters ............................................................................................................... 129 Return Parameters (Error Handling)........................................................................................ 130 Selection Parameters ................................................................................................................ 134 TestRun Parameters.................................................................................................................. 135 Text Transfer Parameters ......................................................................................................... 136 Tools for Developing BAPIs ..................................................................................................... 137 Defining Methods in the BOR Using BOR/BAPI Wizard ........................................................ 138 Converting Internal and External Data Formats ..................................................................... 140 Application Example ............................................................................................................... 142 SAP Enhancements to Released BAPIs.................................................................................. 144 Compatible Enhancements....................................................................................................... 146 Incompatible Enhancements .................................................................................................... 148 Customer Modifications and Developments........................................................................... 151 BAPI Modifications .................................................................................................................... 152 Creating Subtypes .................................................................................................................. 156 Redefining BAPIs ................................................................................................................... 157 Defining Delegation Relationships ......................................................................................... 158 BAPI Development..................................................................................................................... 159 Creating Subtypes .................................................................................................................. 160 Namespaces............................................................................................................................... 161 Using BAPIs in Distributed Systems (ALE) ............................................................................ 164 BAPI Quality Checklist .............................................................................................................. 166

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BAPI Programming

BAPI Programming

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BAPI Programming BAPI Programming Guide

BAPI Programming Guide Purpose This document describes the SAP guidelines for developing and implementing Business Application Programming Interfaces [Page 9] (BAPIs). It is targeted at SAP developers and SAP partners who want to implement BAPIs. Customers are also recommended to follow these guidelines when developing BAPIs. All developments should be done in the customer name space; all changes to existing developments objects of the SAP standard are considered to be modifications. (See Namespaces [Page 161]). As these guidelines are targeted for internal use at SAP, procedures or tools may be mentioned that do not apply or are not available to customers. Information that applies internally to SAP is indicated. This document describes the guidelines valid at the time this document was published.

Prerequisites To program and implement a BAPI with these guidelines you need to have: •

Basic knowledge of BAPIs, as described in the BAPI User Guide [Ext.]

•

Knowledge of the ABAP programming language and ABAP Workbench

•

Basic knowledge of the R/3 System

Process Flow To implement a BAPI follow the processes described in the sections below as closely as possible: Defining and Implementing the BAPI [Page 15] Creating Development Objects and Documentation [Page 46] General Programming Guidelines for BAPIs [Page 54] Testing the BAPI and Its Documentation [Page 52] Releasing the BAPI [Page 53] Programming Standardized BAPIs [Page 90] Programming Standardized Parameters [Page 122] SAP Enhancements to Existing BAPIs [Page 144].

In Release 4.6A in the BAPI Explorer [Page 17] project forms are provided that take you step by step through the implementation procedure for BAPIs and enable you to

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BAPI Programming Guide document the development of your BAPIs. For SAP internal development it is obligatory to use a project form. The BAPI Quality Checklist [Page 166] from earlier releases is still provided at the end of this document. Other topics related to developing BAPIs are: Modifications and Customers’ Own Developments [Page 151] Using BAPIs in Distributed Systems (ALE) [Page 164]

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BAPI Programming BAPIs

BAPIs Definition A Business Application Programming Interface (BAPI) is a precisely defined interface providing access to processes and data in business application systems such as R/3.

BAPIs of SAP Business Object Types BAPIs are defined as API methods of SAP business object types. These business object types and their BAPIs are described and stored in the Business Object Repository [Page 11] (BOR). A BAPI is implemented as a function module, that is stored and described in the Function Builder.

BAPIs of SAP Interface Types As of Release 4.5A BAPIs can also describe interfaces, implemented outside the R/3 System that can be called in external systems by R/3 Systems. These BAPIs are known as BAPIs used for outbound processing. The target system is determined for the BAPI call in the distribution model of Application Link Enabling (ALE). BAPIs used for outbound processing are defined in the Business Object Repository (BOR) as API methods of SAP Interface Types. Functions implemented outside the R/3 System can be standardized and made available as BAPIs. For further information see BAPIs Used For Outbound Processing [Page 45].

Integration BAPIs can be called within the R/3 System from external application systems and other programs. BAPIs are the communication standard for business applications. BAPI interface technology forms the basis for the following developments: •

Connecting:

•

New R/3 components, for example, Advanced Planner and Optimizer (APO) and Business Information Warehouse (BW).

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Non-SAP software

•

Legacy systems •

Isolating components within the R/3 System in the context of Business Framework

•

Distributed R/3 scenarios with asynchronous connections using Application Link Enabling (ALE)

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Connecting R/3 Systems to the Internet using Internet Application Components (IACs)

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PC programs as frontends to the R/3 System, for example, Visual Basic (Microsoft) or Visual Age for Java (IBM).

•

Workflow applications that extend beyond system boundaries

•

Customers' and partners' own developments

The graphic below shows how BAPI interfaces enable different types of applications to be linked together.

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BAPIs

BAPIs - Interfaces to the R/3 System R/3 satellite systems / distributed systems (ALE)

Business Workflow BAPI

BAPI BAPI

Business Object

Business Object

BAPI BAPI

Business Object

Internet / Intranet

VisualBasic/JAVA...

BAPI

BusinessObject

BAPI

Business Object

Business Component BAPI

Isolating components in the Business Framework (R/3, R/2)

Business B Component

BusinessBAPI Object BAPI BAPI

Customers and partners‘ own developments

Business Component

For further background information on BAPIs refer to the document BAPI User Guide [Ext.].

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BAPI Programming BOR

BOR Definition The Business Object Repository (BOR) is the object-oriented repository in the R/3 System. It contains the SAP business object types and SAP interface types as well as their components, such as methods, attributes and events. BAPIs are defined as methods of SAP business object types (or SAP interface types) in the BOR. Thus defined, the BAPIs become standard with full stability guarantees as regards their content and interface. For general information on creating business objects see the documentation on SAP Business Workflow [Ext.].

Use The BOR has the following functions for SAP business object types and their BAPIs: •

Provides an object oriented view of R/3 System data and processes. R/3 application functions are accessed using methods (BAPIs) of SAP Business Objects. Implementation information is encapsulated; only the interface functionality of the method is visible to the user.

•

Arranges the various interfaces in accordance with the component hierarchy, enabling functions to be searched and retrieved quickly and simply. This finds the functionality searched for quickly and simply.

•

Manages BAPIs in release updates. BAPI interface enhancements made by adding parameters are recorded in the BOR. Previous interface versions can thus be reconstructed at any time. When a BAPI is created the release version of the new BAPI is recorded in the BOR. The same applies when any interface parameter is created. The version control of the function module that a BAPI is based on is managed in the Function Builder.

•

Ensures interface stability. Any interface changes that are carried out in the BOR, are automatically checked for syntax compatibility against the associated development objects in the ABAP Dictionary.

Integration A BAPI is implemented as a function module, that is stored and described in the Function Builder. You should only define a BAPI as a method of an SAP business object type in the BOR, if the function module that the BAPI is based on has been fully implemented. Access to the BOR is restricted at SAP.

BOR/BAPI Wizard The BOR/BAPI Wizard [Page 138] helps you to create new BAPIs in the BOR. It takes you through the process step by step.

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BOR

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BAPI Programming Terminology

Terminology Definition The table below contains definitions of the terms used in this document: Term/Synonym

Definition

Object type

Generic definition of business objects. Describes the general characteristics and common attributes of instances of SAP business object types.

Business object type SAP business object type Business object

One instance of an SAP business object type

Business object instance SAP business object instance BOR Business Object Repository BAPI Business Application Programming Interface

Central repository within the R/3 System containing all the business object types and SAP interface types together with their definitions and methods. Standardized programming interface enabling external applications to access business processes and data in the R/3 System. BAPIs are defined in the BOR as methods of SAP business object types that carry out specific business functions. BAPIs are implemented as RFC-enabled function modules and are created in the Function Builder of the ABAP Workbench.

Interface type SAP interface type

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Definitions of attributes, methods and events grouped together in one context. An object type can support one or more interface types. The functional group of associated attributes, methods and events defined for the interface type together with their interfaces are used by the object type and are inherited by the respective subtypes of the object.

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Further Documentation on BAPIs

Further Documentation on BAPIs In the Open BAPI Network under the URL www.sap.com/bapi application developers can view the latest information on BAPI developments undertaken by SAP and by partners. The following R/3 documentation contains further information about developing BAPIs and developing with BAPIs: Document BAPI User Guide [Ext.]

Information about using BAPIs in application programs.

BAPI Programming Guide [Page 7]

Describes how BAPIs are developed in SAP and what guidelines you have to follow. This document can also be used by customers and partners, who want to develop their own BAPIs, or enhance SAP BAPIs.

ALE Programming Guide [Ext.]

Information about ALE technology (Application Link Enabling), including guidelines on using and programming BAPIs implemented in ALE distributed environments.

Library of ALE Business Processes [Ext.]

Overview of ALE business processes (application scenarios of Application Link Enabling). ALE business processes delivered in the standard system are preconfigured and include important application examples of the distribution of business functions and processes.

BAPI ActiveX Control [Ext.]

Describes how external client applications can use SAP’s BAPI ActiveX Control to access SAP business objects.

Calling BAPIs with BAPI Control [Ext.] in the Tutorial: Communication Interfaces [Ext.]

Describes how business objects are called from the R/3 System using SAP’s BAPI ActiveX Controls and how the data is displayed using Table View Controls

SAP Automation RFC and BAPI Interfaces [Ext.]

Describes how C++ and Java class libraries are used to access BAPIs on C++ and Java platforms.

R/3 DCOM Component Connector [Ext.]

Describes how the R/3 DCOM Component Connector developed jointly by SAP and Microsoft is used to integrate R/3 objects and COM objects seamlessly. SAP business objects and their BAPIs can be called directly from COMbased development tools. COM components are also provided in the SAP development environment. The R/3 DCOM Component Connector SDK is shipped as part of RFC SDK for Windows NT.

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BAPI Programming Defining and Implementing the BAPI

Defining and Implementing the BAPI Purpose Various components of the ABAP Workbench are used when you define and implement a BAPI. These are shown in the graphic below. BAPIs are defined in the Business Object Repository (BOR) as API methods of SAP business object types. BAPIs are implemented in the Function Builder as RFC-enabled function modules. The definitions and descriptions of the data structures used by the BAPI are stored in the ABAP Dictionary.

BOR, Function Builder and ABAP Dictionary

ABAP Workbench Business Object Repository

Function Builder

Business Object BO:

Function module BAPI_BO_M1

Method 1 = M1 Method 2 = M2

Function module BAPI_BO_M2

ABAP Dictionary

Definition and description of data structures

Prerequisites For function modules that implement BAPIs, certain standards and rules must be adhered to over and above the standard programming rules for function modules. The following sections guide you through the steps involved in developing a BAPI. The sections contain information about the guidelines and conventions that you should adhere to when defining and implementing a BAPI. When implementing BAPIs follow the requirements below to ensure you achieve consistent behavior and representation of BAPIs as object-oriented methods of SAP business object types or SAP interface types.

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Defining and Implementing the BAPI

Process Flow The development of a BAPI is divided into the steps below (see also the appropriate project template in the BAPI Explorer [Page 17] or the BAPI Quality Checklist [Page 166]):

Task

For further information see:

1. Defining the scenario in which the BAPI will be used

Defining the Scenario [Page 21]

2. Reviewing the BAPI scenario and how the BAPIs interact with one another

Reviewing the Scenario Concept [Page 23]

3. Defining a BAPI and Its Interface

Defining the BAPI and Its Interface [Page 24]

4. Creating individual programming objects

Creating Development Objects and Documentation [Page 46]

5. Programming BAPIs

General Programming Guidelines for BAPIs [Page 54]

6. Testing the BAPI and its documentation

Testing the BAPI and Its Documentation [Page 52]

7. Releasing the BAPI

Releasing the BAPI [Page 53]

8. Enhancing existing BAPIs, if required

SAP Enhancements to Existing BAPIs [Page 144]

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BAPI Programming BAPI Explorer

BAPI Explorer Definition The BAPI Explorer is the R/3 System working environment for developing BAPIs themselves and for developing with BAPIs.

Use Prerequisites The BAPI Explorer is available as of Release 4.6A and enhances or replaces the BAPI Browser used in earlier releases. The BAPI Explorer uses the latest HTML control technology. For this reason to work with the BAPI Explorer, you must be using a SAPgui of version 4.6A. If you are using a SAPgui from an earlier release, the BAPI Browser (Transaction BAPI45) is automatically called instead of the BAPI Explorer. For information about working in the BAPI Browser see BAPI Browser [Ext.] in the BAPI User Guide.

Purpose In the BAPI Explorer, application developers can get an overview of the status of BAPIs in the BOR. The BAPIs can be determined either by the position of the associated obect or interface type in the component hierarchy in the BOR, or from an alphabetical list. All information required to use a particular BAPI is provided in the BAPI Explorer. The BAPI Explorer is used internally in SAP to develop BAPIs, but can also be used by customers and partners. The BAPI Explorer provides all the tools used to create BAPIs and the required development objects in an integrated programming environment. The entire development process of a BAPI takes place in the framework of form-controlled "projects" to achieve maximum quality, stability and usability of the BAPI.

Structure The BAPI Explorer is divided into two areas: •

Hierarchy display Here all the business object types or interface types for which BAPIs have been defined are displayed. For further information see Working with Display Functions [Page 18].

•

Work area Here the details and documentation of the development object selected in the hierarchy display can be viewed. The tools used to develop BAPIs are also available in the work area. For further information see Working with Tools and Projects [Page 20].

Integration To call the BAPI Explorer choose Tools → Business Framework → BAPI Explorer. To call it directly use Transaction BAPI.

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Working with Display Functions

Working with Display Functions Use In the hierarchy display of the BAPI Explorer all the business object types or interface types for which BAPIs have been defined are displayed. Using the tabs Alphabetical and Hierarchical in the hierarchy display, you can select whether the business object types or interface types are displayed alphabetically or as they are assigned in the component hierarchy in the BOR. By expanding the relevant nodes you can navigate up to the parameter level of individual BAPIs.

Features The following display functions are also provided which enable you to directly access BAPIs and their details in the BOR. •

Displaying details Under the Detail view of the work area all the technical details of the development object selected in the hierarchy are displayed. In most cases you can double-click on a field in the Detail display to get to the developent environmnt or to display further information. For example, in the detail display for a particular method, by double clicking on the name of the function module, it will be displayed in the Function Builder.

•

Displaying and Printing Documentation In the Documentation view of the work area the documentation for the development object selected in the hierarchy is displayed. The data element documentation for each parameter field is contained in the documentation for structured BAPI parameters. If you have installed Microsoft Internet Explorer Version 4.0 on the front-end computer, you can print the documentation using the standard SAPgui print function.

•

Changing the level of the hierarchy display The component hierarchy may have many hierarchy levels. To make it easier to find a business object type and its BAPIs, you can use the function Goto → Change hierarchy level to limit the display to two hierarchy levels.

•

Specifying the BAPIs to be displayed The default is to display only released BAPIs of business object types. By choosing Goto → BAPIs to display, you can display all the BAPIs contained in the BOR, that is BAPIs of SAP interface types and BAPIs that have not yet been released. Business object types and interface types are identified by different symbols. To display these, choose Goto → Display legend.

•

Searching for BAPIs Using the standard functions Find and Find next you can search the displayed business object types or interface types using specified criteria (placeholders such as ' * ' can be used):

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BAPI Programming Working with Display Functions

−

Object name, e.g. BusinessProcess

−

Object type (technical object name) e.g. SAP0001

−

Object description, e.g. Plan*

−

Method name, e.g. GetList

−

Method description, e.g. object list*

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Working with Tools and Projects

Working with Tools and Projects Use The views Tools and Projects in the work area are mainly used for developing BAPIs.

Features Depending on the development object selected in the hierarchy display, in the Tools view, the following tools and navigation options are provided: •

Direct access to the Business Object Builder, Function Builder and ABAP Dictionary.

•

List generator to create lists of BAPIs using specified selection criteria.

In the Project view you can create projects to assist you with following and documenting the development procedures below: •

Implementing new BAPIs (for internal SAP use, BAPI developments must be carried out and documented using a project in the BAPI Explorer)

•

Changing released BAPIs (only for SAP internal use)

•

Requesting a new business object type (only for SAP internal use)

For each of these projects there is a project form that takes you step by step through the entire development process and provides direct navigation options to the required development tools and information. Within the project management you can save and delete your projects and you can edit the projects managed by other users by selecting Other users. If you have installed Microsoft Internet Explorer Version 4.0 on the front-end computer, you can print the project form using the standard SAPgui print function.

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BAPI Programming Defining the Scenario

Defining the Scenario Purpose Before you program a BAPI you should clearly define the processes and situations the BAPI will be used for. BAPIs should only be implemented within the context of a meaningful business scenario. For examples of BAPI scenarios refer to Overview of ALE Integration Scenarios [Ext.] in the Library of ALE Business Processes. SAP developers will also find templates for defining and documenting BAPI scenarios.

Process Flow To define the scenario the BAPI is to be used in, consider the following issues: •

Which scenario is to be implemented? Every BAPI should be based on a model of a scenario in which it can be usefully employed. Keep in mind whilst you are planning the scenario that COMMIT WORK commands must not be used in BAPIs. COMMIT WORK commands can adversely effect the process flow of the scenario and how the BAPIs in the scenario work together.=

•

Which SAP business object types are required and do they exist? From the scenario definition you can get information about the SAP business object types relevant to the BAPI scenario. If the business object types required do not exist, they must be created. For information about creating SAP business object types see the documentation, SAP Business Workflow [Ext.]. For SAP internal development you have to complete a business object request form in the BAPI Explorer.

A BAPI is required to read the data of a company code. First of all, a list of all company codes is to be displayed. From this list a company code can be selected, and then using another BAPI, details about this company code are to be displayed. The relevant SAP business object type for this scenario is CompanyCode. •

What functionality should the BAPI provide and how does it affect related BAPIs, especially the other BAPIs of the SAP business object type in question? In line with the scenario concept, BAPIs must complement each other to create a complete scenario. Their relationships with each other must be clearly defined.

To read the details of a company code as described in the above example scenario, two BAPIs are required: •

To display all the company codes

•

To display a specific company code

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Defining the Scenario The interdependency between these two BAPIs is evident because first the list of company codes is displayed to obtain the ID of the specific company code sought. From this ID details of the company code can be displayed. However, the two BAPIs remain functionally independent of each other, because if the company code ID is known, the BAPI "Display details of a specific company code" can be used without first calling the BAPI "Display list of all company codes". •

To what extent can the BAPI's functionality be implemented within the scope of the business object? A BAPI should be developed so that it provides functionality exclusively within the context of its associated SAP business object type. If the data of a different SAP business object type is to be read or updated then the appropriate interface for this object type must be used. The functions or methods of these other object types are used implicitly.

The BAPIs required to read the details of a company code in the above example scenario are only able to access data in the SAP business object type CompanyCode. Other object types are not involved. •

Is the BAPI assigned to the SAP business object type in a meaningful and semantically correct way?

Result Once you have considered these issues you will be able to clearly conceptualize the functionality of the planned BAPI(s).You will also have identified the SAP business object types relevant to the BAPI scenario.

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BAPI Programming Reviewing the Scenario Concept

Reviewing the Scenario Concept Purpose In the previous step you created a concept for a scenario a BAPI could be applied to. You also defined the relevant SAP business object types. Before you implement the scenario and begin defining and developing the BAPI, you should carry out a review of the scenario.

Process Flow You should carry out the review of the BAPI scenario together with all the people involved in the development of the BAPI and those responsible for quality control in your development group. Confirm that the scenario as it stands is meaningful and that the BAPIs in the scenario can interoperate without any problems. Start developing the BAPI only after you have successfully completed the review.

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Defining a BAPI and Its Interface

Defining a BAPI and Its Interface Purpose After you have carried out the review of the BAPI concept and it has been accepted, you can start defining the BAPI itself. In this step, you will decide on the names, parameters, and characteristics of the BAPI and determine the structures in the ABAP Dictionary which the BAPI will be based on. Only after you have planned and defined these required details can you start to implement the BAPI and create the required programming objects. The table below illustrates where the planned information is written and how it fits together.

Information in the BOR, Function Builder and ABAP Dictionary Business Object Repository (BOR)

Function Builder

Business object : CompanyCode

Function module

Interfaces

: ....

Parameter Importing : COMPANYCODEID

Key fields

: CompanyCodeId : ....

Methods

: GetDetail :

Exporting : COMPANYCODE_DETAIL COMPANYCODE_ADDRESS

Attributes

Parameters

: BAPI_COMPANYCODE_GETDETAIL

RETURN

CompanyCodeDetail CompanyCodeAddress Return

Events

: ....

ABAP Dictionary Structures Fields

BAPI 0002_2 : COMP_CODE : BAPI0002_3 : BAPIRET2 :

Process Flow To implement your BAPI in accordance with the required conventions, follow the guidelines for each of the tasks below. Follow the instructions in the references given in the second column.

Task

For further information see:

1. Check if the BAPI is in the Standardized BAPIs category.

Standardized BAPIs [Page 26]

These BAPIs provide basic functions and can be implemented for most of the SAP business object types. Check whether the BAPI can be implemented as a standardized BAPI.

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BAPI Programming Defining a BAPI and Its Interface

2. You have to identify the SAP business object type in the Business Object Repository or if necessary, create one. Test whether the key fields of the business object type are relevant for your BAPI. 3. Define the structure and the scope of the BAPI interface

Determining the Object Type and Its Key Fields [Page 31] For information about creating SAP business object types see the documentation, SAP Business Workflow [Ext.]. Defining the Interface Structure of the BAPI [Page 32] and Standardized Parameters [Page 29]

4. Give names to the required parameters in the function module.

Naming Parameters in the Function Module [Page 34]

5. Define the data formats in which the values must be transferred in the function module interface.

Defining Data Formats [Page 36]

6. Specify the required data objects in the ABAP Dictionary.

Specifying Development Objects in the Dictionary [Page 37]

7. Assign a name to the method in the BOR.

Naming the Method in the BOR [Page 40]

8. Assign a name to the method parameter in the BOR.

Naming Parameters in the BOR [Page 41]

9. Specify the name of the function module that the BAPI is based on, and the name of the function group in which the function module is to be stored.

Naming the Function Module and the Function Module Group [Page 43]

Result Once you have completed these steps, you will have defined your BAPI.

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Standardized BAPIs

Standardized BAPIs Use Some BAPIs and methods provide basic functions and can be used for most SAP business object types. Such BAPIs are known as “standardized” BAPIs.

Features With object methods and especially with BAPIs, you can differentiate between instance methods and class methods. Instance methods refer to precisely one instance (one specific occurrence) of an SAP Business Object type, for example, to one explicitly specified customer order. Whereas class methods are instance-independent.

BAPIs for Reading Data The following BAPIs provide you with read-only access to data in the associated business object type: GetList() With the BAPI GetList() you can select a range of object key values, for example, company codes and material numbers. The BAPIs GetList() is a class method. For more information see Programming GetList() BAPIs [Page 91]. GetDetail() The BAPI GetDetail() uses a key to retrieve details about an instance (one specific occurrence) of a business object type and returns this data to the calling program. Then this information is reported back to the calling program. The BAPI GetDetail() is an instance method. For more information see Programming GetDetail() BAPIs [Page 93]. GetStatus() The BAPI GetStatus() is used to query the status of an SAP business object instance, for example, the processing status of a sales order. This BAPI is used only for displaying the status of an object and does not retrieve full details like the BAPI GetDetail(). The BAPI GetStatus() is an instance method. For more information see Programming GetStatus() BAPIs [Page 96]. ExistenceCheck() The BAPI ExistenceCheck() checks whether an entry exists for a business object instance, for example, whether the customer master has been created. The ExistenceCheck() BAPI is an instance method. For more information see Programming ExistenceCheck() BAPIs [Page 98].

BAPIs for Creating or Changing Data The following BAPIs can create, change or delete instances of a business object type:

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BAPI Programming Standardized BAPIs

Create() or CreateFromData() The BAPI Create() or CreateFromData() creates an instance of an SAP business object type, for example, a purchase order. These BAPIs are class methods. For more information see Programming Create() BAPIs [Page 102]. Change() The BAPI Change() changes an existing instance of a SAP business object type, for example, a purchase order. The () BAPI is an instance method. For more information see Programming Change() BAPIs [Page 106]. Delete() and Undelete() The BAPI Delete() deletes an instance of an SAP business object type from the database, for example, a purchase order. The BAPI Undelete() removes a deletion flag. These BAPIs are instance methods. For more information see Programming Delete() BAPIs [Page 110]. Cancel() Unlike the BAPI Delete () the BAPI Cancel() cancels an instance of a business object, that is the instance to be cancelled remains in the database and an additional instance is created that is canceled). The Cancel() BAPI is an instance method. For more information see Programming Cancel() BAPIs [Page 113]. Add and Remove The BAPI Add adds a sub-object to an existing object instance and the BAPI and Remove removes a sub-object from an object instance. These BAPIs are instance methods. For further information see Programming Methods for Sub-Objects [Page 120].

If you are implementing BAPIs that create or change data you should consider using buffering. For further information see Buffering for Write BAPIs [Page 77].

BAPIs for Mass Processing The BAPIs listed in the above section, “BAPIs for Creating or Changing Data”, can also be used for mass processing. Here, when a BAPI is called, several business object instances are processed at the same time. With BAPIs for mass processing, the suffix “Multiple” is added to the method name, for example, ChangeMultiple(), CreateMultiple(), DeleteMultiple(). The BAPIs here are always class methods.

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Standardized BAPIs

We strongly recommend that you create instance-dependent BAPIs with buffering instead of Multiple() BAPIs. For further information see Buffering with Write BAPIs [Page 77].

BAPIs for Replicating Business Object Instances The following BAPIs are used for replicating business object instances: Replicate() and SaveReplica() The BAPIs Replicate() and SaveReplica() are implemented as methods of replicable business object types(). They enable specific instances of an object type to be copied to one or more different systems. These BAPIs are used mainly to transfer data between distributed systems within the context of Application Link Enabling (ALE). These BAPIs are class methods. For more information see Programming Replicate()/SaveReplica() BAPIs [Page 115].

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BAPI Programming Standardized Parameters

Standardized Parameters Use There are some parameters that can be created for various BAPIs because they contain the same or equivalent data in all BAPIs. Such parameters are known as “standardized” parameters. They should be implemented the same in all BAPIs.

Features Address parameters Specific reference structures are defined for address parameters in BAPIs. You should copy these structures to use in your BAPI, especially if the underlying object type uses the central address management (CAM). For more information see Address Parameters [Page 123].

Change Parameters In BAPIs that cause database changes (for example, Change() and Create() BAPIs) you must be able to distinguish between parameter fields that contain modified values and parameter fields that have not been modified. This distinction is made through the use of standardized parameters. For more information see Change Parameters [Page 125].

Extension parameters The parameters ExtensionIn and ExtensionOut provides customers with a mechanism that enables BAPIs to be enhanced without modifications. For further information see Customer Enhancement Concept for BAPIs [Page 65].

Return Parameters Each BAPI must have an export Return parameter for returning messages to the calling application. To provide application programmers with a consistent error handling process for BAPI calls, all Return parameters must be implemented in the same, standardized way. For further information see Return Parameters (Error Handling) [Page 130].

Selection Parameters The parameters in BAPIs used to search for specific instances of a business object type, for example, BAPI GetList(), have to enable the caller of the BAPIs to specify appropriate selection criteria. Standardized selection parameters are used to do this. For more information see Selection Parameters [Page 134].

Test Run Parameters The parameter TestRun is used in the BAPIs that generate instances - Create() or CreateFromData(), to check the entries for the object instance in the database before actually creating the object instance. The creation of the object instance is only simulated and data is not updated.

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Standardized Parameters For further information see Test Run Parameters [Page 135].

Text Transfer Parameters To transfer BAPI documentation texts, for example, documentation of a business object type, you have to create standardized text transfer parameters. For more information see Text Transfer Parameters [Page 136].

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BAPI Programming Determining the Object Type and Its Key Fields

Determining the Object Type and Its Key Fields Purpose Object type You have to identify the SAP business object type required for your BAPI in the Business Object Repository or if necessary, create one. For information about creating SAP business object types see the documentation, SAP Business Workflow [Ext.]. For SAP internal development you have to complete a business object request form in the BAPI Explorer.

Key Fields A key is defined in the BOR for the majority of SAP business object types. This key may consist of several key fields which are used to identify an individual single instance of the SAP business object type. You can differentiate between instance-dependent (instance methods) and instance-independent (class methods) BAPIs. Unlike instance-independent methods, instance-dependent methods relate to one instance (one specific occurrence) of an SAP business object type, for example to one specific sales order. In the case of instance-dependent BAPIs, the key fields of the corresponding SAP business object type must be used as parameters in the function module the BAPI is based on so that the associated object instance can be identified. For further information see Defining the Interface Structure of the BAPI [Page 32]. The names of the key fields in the SAP business object type and the corresponding parameters in the BAPI function module must be the same, because the name links the key fields to the parameters.

The SAP business object type, CompanyCode, has a key field named CompanyCodeId. This key field must be defined as a parameter with the name COMPANYCODEID in the function modules of the instant-dependent BAPIs for this business object type.

Process Flow To display a business object type and its key fields: 1. Select Tools →=ABAP Workbench → Overview →=Business Object Browser=. The business object types are displayed in the order of the R/3 application hierarchy. 2. Select the required SAP business object type in the application hierarchy and double click it to open it. 3. To display the business object type’s key fields, expand the node Key fields.

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Defining the Interface Structure of the BAPI

Defining the Interface Structure of the BAPI Purpose In this step you are going to define the scope and interface structure of the BAPI, that is, the individual import, export and table parameters required for calling the BAPI. You will specify the names of these parameters in the section Naming Parameters in the Function Module [Page 34]

You cannot use change and exception parameters in a function module which implements a BAPI.

Process Flow Try to structure the BAPI as clearly as possible. Match the import parameters with each other to avoid having redundant data in the interface. To identify the interface parameters for your BAPI, proceed as follows: 1. Check that the key fields of the SAP business object type in question are required and specify how they are going to be used in the BAPI interface. The key fields of the SAP business object type are some of the most important BAPI parameters. •

If a key value is to be passed to the BAPI by the calling program, the key field must be set as an import parameter in the function module of the BAPI. That way a specific instance of the business object type is identified. For example, this could be a customer number (CustomerNo) in the BAPIs Customer.GetDetail() and Customer.CheckPassword(), or the number of a sales document in the BAPI SalesOrder.GetStatus().

•

For BAPIs that generate instances, for example, the BAPIs Create() or CreateFromData(), each key field of the business object type should be set as an export parameter in the BAPI function module. These BAPIs return one key value, for example, an order number in the BAPI SalesOrder.CreateFromData().

•

For BAPIs that are class methods no key field is set as the BAPI function module’s own parameter. Class methods are instance-independent and are called without the use of key values. Usually they return a table with a selection of key values. Exceptions are write BAPIs, as described in the list item above.

2. Specify what other data is relevant in import, export or table parameters for the BAPI. Check that the parameters can be implemented as standardized parameters. You have to create an export parameter, Return, to send messages back to the calling program. For details see Return Parameters (Error Handling) [Page 130].

The BAPI to be developed is to read data from the SAP business object type CompanyCode. To read the company code, the calling program has to specify the ID

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BAPI Programming Defining the Interface Structure of the BAPI

of the company code. The returned information should include detailed data and address data. To map these requirements to the BAPI interface, the following parameters must be created in the function module which the BAPI is based on: •

The key field CompanyCodeID of the SAP business object type as an import parameter

•

A Return parameter that reports messages back to the calling program

•

A parameter for the details of the company code.

•

A parameter for the address data of the company code.

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Naming Parameters in the Function Module

Naming Parameters in the Function Module Purpose In the previous step you identified the scope and the required contents of the interface parameters. Now you have to specify the names of these parameters in three function module.

Process Flow You are only allowed to define export, import and table parameters for the BAPI function module interface. Change and exception parameters are not allowed. The names you choose for the function module parameters are used in the Business Object Repository (BOR) as the names of the associated method parameters. The names of BAPI parameters in the BOR and the names of the parameters in the associated function module must be identical. For this reason parameters in function modules must have meaningful names in English to ensure the BAPI method call can be carried out without any problems. When assigning parameter names follow the guidelines below: •

The names must be in English.

•

As of Release 4.5A the names of method parameters in the BOR can be up to 30 characters long. Parameter names in function modules that implement the BAPIs can therefore also have up to 30 alphanumeric characters. (In earlier Releases names of parameters in the BOR could only be a maximum of 20 characters long. The associated parameter names in the function module could only be 20 characters long).

•

Choose meaningful names and do not use abbreviations.

In the above example based on the company code scenario, the following parameters were required: •

An import parameter for the key field CompanyCodeID of the SAP business object type CompanyCode

•

An export parameter for the detailed data of the company code.

•

An export parameter for the address data of the company code.

•

A return parameter that reports messages back to the calling program You could use the following names for these parameters in the function module:

Contents Company code Detailed data of company code Address data of company code Return Parameters

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Name in Function Module COMPANYCODEID COMPANYCODEDETAIL COMPANYCODEADDRESS RETURN

Parameter Type IMPORTING EXPORTING EXPORTING EXPORTING

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BAPI Programming Naming Parameters in the Function Module

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Defining Data Formats

Defining Data Formats Purpose Here you specify the formats in which the data has to be transferred in the function module interface. BAPIs are not end user interfaces, they are programming interfaces that can be used in diverse application areas, for instance, to connect non-SAP systems and PC products to the R/3 System. Fields in BAPI parameters must be presented in a neutral form used in the database and not in a form formatted in the BAPI interface. •

Data must not be presented in a user-dependent or language-dependent format. For example, the date in a BAPI must be in the internally used format YYYYMMDD, where YYYY is the year, MM the month and DD the day.

•

Standard codes, such as ISO codes must be used, whenever possible.

Exceptions SAP-specific data formats must be converted into the data format required externally. This applies to, for example: •

Currency amount fields

•

Quantity fields

•

Fields that have an internal key

•

Specific fields in address structures

To do this you can generate function modules that can map the relevant data to each other and perform the conversion. For further information about these exceptions see Internal and External Data Formats [Page 69].

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BAPI Programming Specifying Development Objects in ABAP Dictionary

Specifying Development Objects in ABAP Dictionary Purpose After you have specified the contents and names of the required interface parameters, you can identify and define the required data objects in the ABAP Dictionary.

Process Flow Note the following guidelines: •

You can use individual fields, structures and tables as parameters. Every parameter must refer to a Dictionary object. Note that all the parameters must be defined as structures. If a parameter consists of one field only, this must be linked to a field in a BAPI structure. Complex data types, such as table fields in structures, are not allowed.

•

You have to create your own data structures for the BAPI interface that are independent of the data structures generally used in the R/3 application. This enables changes to be made in R/3 applications without affecting BAPIs. Give meaningful names to the data structures you create. Names should begin with the prefix BAPI.

•

You must not use INCLUDE structures in BAPI structures, because enhancements to INCLUDE structures generally lead to incompatible changes to the BAPI structure. For further information see Incompatible Enhancements [Page 148]. BAPI structures themselves should not be used in other structures.

Structure S1 consists of fields F1 and F2. Structure S2 includes structure S1 and has a field F3. If a field F3 is added to structure S1, this causes an incompatible change to structure S2 and leads to a name clash of the F3 fields. The graphic below illustrates the problem: Original structures: Structure S1

F1

F2

Structure S2

F1

F2

Structure S2 includes structure S1 F3

Structures after adding field F3: Structure S1

F1

F2

F3

Structure S2

F1

F2

F3

F3

Problems in structure S2: • Field added in the middle of structure (incompatible change) • Two fields have the same name (naming conflict)

•

You can use existing data elements and domains for fields in BAPI structures. If possible only use central data elements and domains contained in Basis Development or in Application Basis. The associated development classes begin with B or S.

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Specifying Development Objects in ABAP Dictionary Before you use an existing data element or domain, you should consult the respective colleague responsible for the object. •

Choose meaningful names in English for the fields in the structures. Up until Release 4.0 ten characters were available for naming structures; from Release 4.0 you can use up to 30 characters. You can use alphanumeric characters and underscores. As of Release 4.0 default field names in English exist for data elements in the ABAP Dictionary. Whenever possible use these names for the field and parameter names. The report BBAPIFLD generates the English default names for the fields and parameters. To use this report refer to the report documentation. If German field names are used in the internal work structures of a BAPI you can use the transaction described in Converting Between Internal and External Data Formats [Page 140], to convert the German field names into English.

In the example in the previous steps, the reference fields/tables shown below were identified for the parameters. The first example here uses structures created in Release 3.1. In this Release structure names had a maximum of 10 characters. The second example shows how you could name the structures more meaningfully in Release 4.0.

Parameters and their Reference Fields in Release 3.1 Parameter in the Function Module

Reference Field/Table

COMPANYCODEID

BAPI0002_2-COMP_CODE

COMPANYCODEDETAIL

BAPI0002_2

COMPANYCODEADDRESS

BAPI0002_2

RETURN

BAPIRETURN1

Parameters and their Reference Fields in Release 4.0

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Parameter in the Function Module

Reference Field/Table

COMPANYCODE

BAPI0002_2-COMP_CODE

COMPANYCODEDETAIL

BAPI0002_COMPANYCODEDETAIL

COMPANYCODEADDRESS

BAPI0002_COMPANYCODEADDRESS

RETURN

BAPIRETURN1

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BAPI Programming Specifying Development Objects in ABAP Dictionary

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Naming the Method in the BOR

Naming the Method in the BOR Process Flow You can now specify the name of the BAPI as a method of a SAP business object type in the Business Object Repository (BOR). The individual components of BAPI names are identified by the use of upper and lower case letters, for example, ChangePassword. BAPI names must be meaningful and be in English, and can only have a maximum of 30 characters. For example: •

ExistenceCheck

•

ChangePassword

•

GetDetail

For standardized BAPIs use the corresponding generic name, for example, GetList, GetDetail. For further information about these BAPIs see Standardized BAPIs [Page 26].

In standard, object-oriented language use, parentheses() are added to the method name, for example GetList(), in documentation and user guides. This convention is also used in the document. However, no parentheses are used when assigning BAPI names. To get an idea about naming BAPIs, you should take a look at the existing BAPIs of an SAP business object type in the BOR.

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BAPI Programming Naming Parameters in the BOR

Naming Parameters in the BOR Process Flow You can now assign names to the individual method parameters in the Business Object Repository (BOR). These names are based on the names of the parameters in the function module that you assigned in Naming Parameters in the Function Module [Page 34]. When naming BAPI parameters in the BOR follow the guidelines below: •

The components of parameter names in the BOR are separated by upper and lower case letters to make them easier to read. Each new word in the parameter name begins with a capital letter, for example, CompanyCodeDetail.

•

From Release 4.0 the names of BAPI parameters in the BOR and the names of the parameters in the associated function module must be identical except for the use of upper and lower case letters. This was not necessarily the case for BAPIs developed before Release 4.0.

•

Standardized parameters have specified names. For more information see Programming Standardized Parameters [Page 122]. If you create your BAPI in the BOR using the BOR/BAPI Wizard, the Wizard uses the parameter names in the function module as the default names of the method parameters. For information about the BOR/BAPI Wizard see Defining Methods in the BOR Using the BOR/BAPI Wizard [Page 138].

•

Parameter names in the BOR must be in English.

•

Parameter names in the BOR cannot be more than 30 characters.

In the example in the previous steps, four parameters for one BAPI were identified and the names of these parameters specified in the function module. The table below shows what the parameter names could look like in the function module and in the BOR.

Parameters and their Names in the Function Module and in the BOR Contents

Name in Function Module

Name in the BOR

Company code

COMPANYCODE

CompanyCode

Detailed data of company code

COMPANYCODEDETAIL

CompanyCodeDetail

Address data of company code

COMPANYCODEADDRESS

CompanyCodeAddress

Return Parameters

RETURN

Return

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Naming Parameters in the BOR

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BAPI Programming Naming the Function Module and the Function Module Group

Naming the Function Module and the Function Module Group Purpose Here you specify the name of the function module the BAPI is based on. You must also specify the function group which this function module is to be assigned to. If there is not an appropriate function group, you have to specify a name for a new function group.

Process Flow Assigning a Name to the Function Module Choose a name for the function module which gives an indication of what the BAPI is used for. The naming convention for BAPIs is BAPI__. You cannot exceed the maximum length of 30 characters. If required, you can shorten the name of the method, but the BAPI_ should always be written in full.

In the case of a GetDetail() BAPI, which reads details for the object type CompanyCode, the name of the associated function module is BAPI_COMPANYCODE_GETDETAIL.

Specifying the Function Group All the BAPIs belonging to an SAP business object type should be created in one or more function groups. BAPIs belonging to different SAP business object types must not be created in the same function group. Ascertain whether a function group has already been created for the BAPIs of the SAP business object type in question. If a function group does not already exist, specify a name for one to be created. As the basis for naming the function group, you can use either the default technical name (object type) of the SAP business object type or its object name. •

The technical name (object type) of an SAP business object type usually takes the form of BUSnnnn, where n is a number. Use the suffix "nnnn" as the technical name of the function group. For example, if the technical name of the object type is BUS1008, then the associated BAPI function group is called 1008. To find out the technical name of the business object type, open the object type in the Business Object Repository (BOR), as described in the section Determining the Object Type and Its Key Fields [Page 31] To display further details, for example, the technical name, double click on the name of the business object type .

•

The object name of an SAP business object type can be used for the name of the function group. For example, all BAPIs associated with the business object type, CompanyCode, could be stored in a function group called Companycode.

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Naming the Function Module and the Function Module Group

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BAPI Programming BAPIs Used for Outbound Processing

BAPIs Used for Outbound Processing Use As of Release 4.5A BAPIs can also be defined which have been implemented outside the R/3 System yet can still be called from the R/3 System. These BAPIs are known as BAPIs used for outbound processing. Unlike the conventional BAPIs that are implemented in the R/3 server system and also called here (inbound), outbound BAPIs are interfaces implemented on the client system. There are always separate systems for defining (client) and for implementing (server) outbound BAPIs. The target system is determined for the BAPI call in the distribution model of Application Link Enabling (ALE).

Integration BAPIs used for outbound processing are defined in the Business Object Repository as API methods of SAP interface types. Functions implemented outside the R/3 System can be standardized and made available as BAPIs. BAPIs both for outbound processing and for inbound processing can be called in the same way via the ALE distribution model.

Features When creating BAPIs for outbound processing keep in mind: •

BAPIs used for outbound processing simply require the interface definition; the function module cannot be programmed.

•

Use the BOR/BAPI Wizard to create a BAPI of an SAP interface type. For further information see Defining Methods in the BOR Using the BOR/BAPI Wizard [Page 138].

•

In Release 4.5A API methods of interface types must have the status “implemented”.

•

BAPIs used for outbound processing can be determined from the BOR using Transaction SWO1. For further information see Determining BAPIs of Interface Types [Ext.] in the BAPI User Guide.

The information contained in the BAPI User Guide [Ext.] and in the BAPI Programming Guide refers to - with the exception of the above-mentioned points BAPIs of both SAP interface types and SAP business object types. If this is not the case, the documentation will explain what the differences are.

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Creating Development Objects and Documentation

Creating Development Objects and Documentation Purpose After you have defined your BAPI, identified the relevant programming objects and given them names, you can create the programming objects in the R/3 System.

Process Flow Task

Tools / Further Information

1. If necessary, create the required SAP business object type in the Business Object Repository.

For SAP internal development you have to complete a business object request form in the BAPI Explorer. For general information about creating business object types refer to the documentation on SAP Business Workflow [Ext.].

2. The data objects, for example, structures, fields and domains are stored in the ABAP Dictionary.

For further information see the ABAP Dictionary [Ext.].

3. Create the function module in the Function Builder and the function group, if required.

For further information see the BC ABAP Workbench: Tools [Ext.].

4. Create the documentation for the BAPI and for each interface parameter and for each parameter field.

For internal BAPI documentation you must follow the current BAPI documentation guidelines which you can get from your contact person in the BAPI Development group.

Documentation on the BAPI and its parameters is essential because it is very difficult to use a BAPI that has not been well documented.

See the general Documentation Guidelines [Page 88].

5. If required, generating the function modules that can convert between the internal and external data formats.

For details on how to do this see Converting Between Internal and External Data Formats [Page 140].

6. Writing the program for the function module that the BAPI is based on.

For further information see General Programming Guidelines for BAPIs [Page 54] and Programming Standardized BAPIs [Page 90]

Note that the COMMIT WORK command must not be used in the function module.

For an example of a function module that implements a BAPI see BAPI Interface and Function Module [Page 48].

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7. Using the BOR/BAPI Wizard, define the function module as a method of the associated SAP business object type in the BOR. Finally, make sure that the parameters and parameter types of the method in the BOR match the parameters of the underlying function module in the Function Builder.

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For more information see Defining Methods in the BOR Using the BOR/BAPI Wizard [Page 138]. For an example of a function module that implements a BAPI see BAPI Interface and Function Module [Page 48].

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BAPI Interface and Function Module

BAPI Interface and Function Module The definition of a BAPI in the Business Object Repository and its associated function module in the Function Builder must correspond to each other. This example shows the relationships between the method and the function module. The graphic below shows the SAP business object type PurchaseOrder (BUS2012) in the BAPI Browser view of the BOR. Note the following: •

The business object type has a key field PurchaseOrder.

•

The method we are looking at, GetDetail(), displays details of a purchase order The method consists of several import, export, and import/export (table) parameters.

Business Object PurchaseOrder with Key Fields and Methods

Function Module BAPI_PO_GETDETAIL This function module BAPI_PO_GETDETAIL implements the BAPI GetDetail() of the business object type PurchaseOrder. Keep in mind the following points when reading the source code extract below: •

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The name of the function module BAPI_PO_GETDETAIL is in the format: BAPI__. Standard abbreviations can be used for business

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BAPI Programming BAPI Interface and Function Module

object types. It is, however, better to write the name of the object type in full, for example, BAPI_PURCHASEORDER_GETDETAIL and, if necessary, to shorten the method name. •

BAPI data structures are used. These are recognized by the prefix BAPI, for example, BAPIEKKOL.

•

As of Release 4.0 the names of the parameters in the method in the BOR must be exactly the same as the names of the parameters in the function module. Underscores in parameter names are no longer allowed.

•

The key field PURCHASEORDER of the business object type is defined as an import parameter.

•

The function module performs authorization checks.

•

The function module picks up exceptions in the Return parameter. From Release 4.5A the reference structure BAPIRET2 or BAPIRET1 must be used.

Source Code Function Module BAPI_PO_GETDETAIL *"---------------------------------------------------------------------*" *"local interface: *" IMPORTING *" VALUE(PURCHASEORDER) LIKE BAPIEKKO-PO_NUMBER *" VALUE(ITEMS) LIKE BAPIMMPARA-SELECTION DEFAULT 'X' *" VALUE(ACCOUNT_ASSIGNMENT) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" VALUE(SCHEDULES) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" VALUE(HISTORY) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" VALUE(ITEM_TEXTS) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" VALUE(HEADER_TEXTS) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" VALUE(SERVICES) LIKE BAPIMMPARA-SELECTION *" DEFAULT SPACE *" *" *" *"

EXPORTING VALUE(PO_HEADER) LIKE BAPIEKKOL STRUCTURE VALUE(PO_ADDRESS) LIKE BAPIADDRESS STRUCTURE BAPIADDRESS

*" *" *" *" *" *" *" *" *" *" *" *" *" *" *"

TABLES

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BAPIEKKOL

PO_HEADER_TEXTS STRUCTURE BAPIEKKOTX OPTIONAL PO_ITEMS STRUCTURE BAPIEKPO OPTIONAL PO_ITEM_ACCOUNT_ASSIGNMENT STRUCTURE BAPIEKKN OPTIONAL PO_ITEM_SCHEDULES STRUCTURE BAPIEKET OPTIONAL PO_ITEM_TEXTS STRUCTURE BAPIEKPOTX OPTIONAL PO_ITEM_HISTORY STRUCTURE BAPIEKBE OPTIONAL PO_ITEM_HISTORY_TOTALS STRUCTURE BAPIEKBES OPTIONAL PO_ITEM_LIMITS STRUCTURE BAPIESUH OPTIONAL PO_ITEM_CONTRACT_LIMITS STRUCTURE BAPIESUC OPTIONAL PO_ITEM_SERVICES STRUCTURE BAPIESLL OPTIONAL PO_ITEM_SRV_ACCASS_VALUES STRUCTURE BAPIESKL OPTIONAL RETURN STRUCTURE BAPIRETURN OPTIONAL

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BAPI Interface and Function Module *"---------------------------------------------------------------------* reset all structures and tables CLEAR: PO_HEADER, PO_ADDRESS, PO_ITEMS, PO_HEADER_TEXTS, PO_ITEM_ACCOUNT_ASSIGNMENT, PO_ITEM_SCHEDULES, PO_ITEM_TEXTS, RETURN, EKPOKEY, PO_ITEM_HISTORY, PO_ITEM_HISTORY_TOTALS, PO_ITEM_LIMITS, PO_ITEM_SERVICES, PO_ITEM_CONTRACT_LIMITS, PO_ITEM_SRV_ACCASS_VALUES, CEKKO, CEKPO, CEKKN, CEKET, CEKAN, SEKKO, SEKPO, CADR. REFRESH: PO_HEADER_TEXTS, PO_ITEM_ACCOUNT_ASSIGNMENT, PO_ITEM_SCHEDULES, PO_ITEM_TEXTS, PO_ITEMS, RETURN, EKPOKEY, PO_ITEM_HISTORY, PO_ITEM_HISTORY_TOTALS, PO_ITEM_LIMITS, PO_ITEM_SERVICES, PO_ITEM_CONTRACT_LIMITS, PO_ITEM_SRV_ACCASS_VALUES, CEKKN, CEKET, SEKKO, SEKPO. * select the header data from database SELECT SINGLE * FROM EKKO WHERE EBELN EQ PURCHASEORDER. IF SY-SUBRC NE 0. PERFORM FILL_BAPIRETURN TABLES RETURN USING 'E' 'W5' '107' PURCHASEORDER SPACE SPACE SPACE. EXIT. ENDIF. * authority check PERFORM PO_AUTHORITY_HEADER TABLES RETURN USING EKKO. IF NO_AUTHORITY NE SPACE. PERFORM FILL_BAPIRETURN TABLES RETURN USING 'E' 'W5' '033' SPACE SPACE SPACE SPACE. EXIT. ENDIF. ……. ……. SORT SORT SORT SORT SORT SORT SORT SORT SORT

PO_ITEMS BY PO_NUMBER PO_ITEM. PO_ITEM_ACCOUNT_ASSIGNMENT BY PO_ITEM SERIAL_NO. PO_ITEM_SCHEDULES BY PO_ITEM SERIAL_NO. PO_ITEM_HISTORY BY PO_ITEM SERIAL_NO. PO_ITEM_HISTORY_TOTALS BY PO_ITEM SERIAL_NO. PO_ITEM_LIMITS BY PCKG_NO PO_ITEM_CONTRACT_LIMITS BY PCKG_NO LINE_NO. PO_ITEM_SERVICES BY PCKG_NO LINE_NO. PO_ITEM_SRV_ACCASS_VALUES BY PCKG_NO LINE_NO SERNO_LINE.

ENDFUNCTION.

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BAPI Programming BAPI Interface and Function Module

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Testing the BAPI and Its Documentation

Testing the BAPI and Its Documentation Purpose After you have implemented the function module your BAPI is based on and you have defined the BAPI as a method of an SAP business object type in the Business Object Repository (BOR) you should check that the BAPI functions properly.

Prerequisites Carry out the test together with persons responsible for quality control in your development group. Before you start testing make sure that the underlying function module has been completely implemented and that the BAPI has been correctly defined in the BOR as method of a business object type.

Process Flow Testing the Documentation Check that the documentation for each business object type, each BAPI and for each interface parameter is available and that you can understand it.

Testing the BAPI You can test the BAPI in the following ways: •

By testing the underlying function module in the Function Builder You can individually test the parameters in your function module by entering the appropriate test values in the parameters to verify that the source code in the function module can run without errors.

•

By testing the BAPI call from an external program. You should ensure that your BAPI can be called from within external programs, for example, from a Visual Basic program using SAP’s BAPI ActiveX Control [Ext.].

Result If you find any errors in the BAPI implementation, correct them and repeat the tests until you and the quality control team in your group are fully satisfied with the BAPI implementation and with the documentation.

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BAPI Programming Releasing the BAPI

Releasing the BAPI After you have completed the function module and BAPI tests, the development of the BAPI is complete. You can now release the function module the BAPI is based on and the method in the Business Object Repository (BOR). Once the BAPI has been released, it becomes available as a fully implemented method of a business object type. Releasing also prevents anyone making incompatible changes to the BAPI, because all changes made to a released BAPI are automatically checked for compatibility in the BOR and the ABAP Dictionary, and incompatible changes are rejected. For more information about what to look out for when making changes to existing BAPIs see SAP Enhancements to Existing BAPIs [Page 144]. The BAPI must be released in cooperation and agreement with the persons responsible for the development objects involved and those responsible for quality control. To release a BAPI follow the steps below: 1. First release the function module in the Function Builder. Select Function module → Release → Release. 2. Set the status of the method to 'released' in the Business Object Builder. 3. Select the relevant SAP business object type in the Business Object Builder and open the node Methods. 4. Place the cursor on your BAPI and select Edit → Change release status → Object type component → In Released. 5. Verify the new status of the function module in the Function Builder and the method in the BOR.

Releasing BAPIs in the Context of ALE If you are implementing the BAPI in an asynchronous context of Application Link Enabling (ALE), you have to also release the IDoc associated with the BAPI. For more information see the ALE Programming Guide [Ext.].

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General Programming Guidelines for BAPIs

General Programming Guidelines for BAPIs Use To ensure that BAPIs, as interfaces of SAP business object types, provide access to R/3 data and processes in a consistent way, you must follow certain rules when programming BAPIs. This section contains general information and guidelines on programming BAPIs. It is difficult to formalize the contents and functional scope of a BAPI. Every BAPI has a different functional content, even those that perform similar functions, for example, the standardized BAPIs. The differences are mainly due to the different characteristics of SAP business object types and their contents.

Guidelines Specific to BAPIs In addition to the general guidelines, you should follow the specific guidelines for programming BAPIs: Programming Standardized BAPIs [Page 90] Using BAPIs in Distributed Systems (ALE) [Page 164]

General Recommendations Keep in mind the following recommendations when developing your BAPI:

Recommendation

For Further Information See:

Minimize interface complexity. Supply the BAPI with the minimum of data and group the data from a business perspective. Structure your BAPI in the most efficient way

Improving Performance [Page 86]

Mandatory Rules You must follow these rules for all BAPIs:

General Mandatory Rules

For Further Information See:

BAPIs must not invoke COMMIT WORK commands.

Transaction Model for Developing BAPIs [Page 58]

BAPIs must not contain the following commands:

Transaction Model for Developing BAPIs [Page 58]

•

CALL TRANSACTION

•

SUBMIT REPORT

•

SUBMIT REPORT AND RETURN

INCLUDE structures must not be used in BAPI structures.

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BAPI Programming General Programming Guidelines for BAPIs

Database changes can only be made through updates.

Transaction Model for BAPIs Without Commit [Page 63]

The global memory must not be used to transfer values.

Transaction Model for Developing BAPIs [Page 58]

Due to transparency it is strongly recommended not to use Set and Get.

Transaction Model for Developing BAPIs [Page 58]

If required every BAPI must be able to carry out its own authorization checks. Values relevant for Customizing are not allowed to be changed.

Programming Create() BAPIs [Page 102] and Programming Change() BAPIs [Page 106]

Language-dependent values cannot be used as interface parameters. BAPIs must not produce any screen output. This means that lists, queries and dialog boxes must not be returned to the calling program. This is true for the BAPI itself and for any function module that may be indirectly called by the BAPI.

Return Parameters (Reporting Errors) [Page 130]

BAPIs must not cause program terminations, they can only return a message (type A: termination message) in the return parameter. Messages of type E (error) and A (termination) cannot be output in the program.

Fields and Parameters You must follow these rules for BAPI fields and parameters:

Mandatory Rules for Fields and Parameters Standardized parameters must be implemented consistently.

For Further Information See: Programming Standardized Parameters [Page 122]

Each BAPI must have a return parameter for returning messages to the calling application.

Return Parameters (Reporting Errors) [Page 130]

All field and parameter names must be in English

Naming Parameters in the Function Module [Page 34] Specifying Development Objects in the Dictionary [Page 37]

All quantity and amount fields must be assigned quantity unit fields. All currency amount fields must be assigned currency IDs.

Internal and External Data Formats [Page 69]

All key fields in GetDetail() and GetList() BAPIs must be displayed as text fields.

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General Programming Guidelines for BAPIs Whenever possible, F4 input help for fields in BAPI parameters must be made available

Providing Input Help (F4 Help) [Page 73]

Data conversion You must follow these rules for data conversions:

Mandatory Rules for Data Conversion

For Further Information See:

Only the internal data format can be used in BAPIs

Internal and External Data Formats [Page 69]

Except for: •

Currency amount fields

•

Quantity fields

•

ISO codes

•

Fields that have an internal key

•

Specific fields in address structures

You must always use a period for the decimal point Currency amounts with decimal points must be formatted with a decimal point in the interface.

Internal and External Data Formats [Page 69]

For example, the value "10.12" must be formatted as "10.12" and not as "1012".

Documentation You must follow these rules for the documentation:

Mandatory Rules for Documentation

For Further Information See:

The business object type must be documented

Business object type documentation is stored in the Business Object Repository. SAP information developers must follow the latest business object type documentation guidelines. You can get these from your contact person in BAPI development.

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BAPI Programming General Programming Guidelines for BAPIs

The business object must be documented All interface parameters must be documented. Note the following guidelines: •

BAPIs with buffering must be identified as

«

such. •

In the case of exceptions: If the BAPI contains a COMMIT WORK command; this must be documented.

•

The documentation on return parameters must describe all possible return values and messages.

•

If, for termination messages, a database rollback is executed in the return parameter, this must be explained in the documentation on the return parameter.

•

Documentation on mandatory parameters must specify which fields must be filled.

•

All mandatory fields in a parameter must be documented as mandatory parameters.

•

All available BAPI table extensions must be listed in the documentation on the extension parameter.

Data element documentation must be written for all the fields in BAPI parameters.

The documentation on the BAPI and the interface parameters is created in the Function Builder for the function module that the BAPI is based on. SAP information developers must follow the latest BAPI documentation guidelines. You can get these from your contact person in BAPI development.

Providing Interface Descriptions [Page 75]

The documentation must be checked for completeness and comprehensibility.

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Transaction Model for Developing BAPIs

Transaction Model for Developing BAPIs Use The transaction model in which BAPIs are used determines how you have to program BAPIs.

Logical Unit of Work (LUW) and Statelessness Within the context of the transaction model used to develop BAPIs, a transaction represents one processing step or one logical unit of work (LUW). An R/3 LUW is all the steps involved in a transaction including updating the database. The whole transaction must be programmed to be stateless. The ACID principle applies to transaction models, meaning that transactions are: •

Atomic When a transaction is called, database operations are either fully executed or not at all. Either all relevant data has to be changed in the database or none at all.

•

Consistent If a transaction is called more than once, each call must have the same result. No data is imported that may indirectly affect the result.

•

Isolated (isoliert) There must be no functional dependencies between two transactions, one transaction must not affect another transaction.

•

Durable Changes cannot be reversed and transactions cannot be canceled.

Features In Release 3.1, the BAPIs themselves executed the COMMIT WORK command, BAPIs had the same purpose as an LUW or transaction.

If a BAPI executes a COMMIT WORK command, this must be mentioned in the BAPI documentation. This is the only way users are able to know that the BAPI contains a COMMIT WORK command. These BAPIs must also be documented in the SAPNet - R/3 Frontend in Note 0131838, "Collective Note for BAPIs with the Commit Work Command". As of Release 4.0 BAPIs cannot execute 'COMMIT WORK' commands. This enables several BAPIs to be combined in one LUW. The outcome is two transaction models: Transaction Model for BAPIs with Commit [Page 60] Transaction Model for BAPIs Without Commit [Page 63]

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BAPI Transaction Model with Commit

BAPI Transaction Model with Commit Use The example below of an external program calling a BAPI to change data in an R/3 System, illustrates how the transaction model affects BAPI development using commit. For example, this could involve a transaction implemented with Visual Basic. Only data from the R/3 System is to be changed. The RFC connection is live the whole time the external program is logged on to the R/3 System to avoid having to connect and disconnect repeatedly. When the RFC connection is already established, an RFC call does not essentially take up any more CPU time than a direct call to the function module from within the R/3 System. There is one BAPI call for each transaction in this transaction model. BAPIs can only be called synchronously. A BAPI call is essentially the call of the underlying RFC capable function module. The process flow of the program consists of the following steps below (see graphic below): Log on ...

Source code

Call BAPI to read and/or change data ...

Source code

Call BAPI to read and/or change data ...

Source code

Log off

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BAPI Programming BAPI Transaction Model with Commit

BAPI Transaction Model with Commit

BAPI call (RFC call of function module)

Visual Basic

...

...

...

...

R/3(ABAP)

Time

Log off

Log on Logical Unit of Work

Logical Unit of Work

“Commit Work“ call RFC session

What do the terms "LUW" and "stateless" mean to BAPIs that have been implemented in the framework of this transaction model? If a transaction represents one Logical Unit of Work and in addition is supposed to be stateless, BAPIs are affected as follows: •

Initial state each time a BAPI is called A repeated call of one BAPI must produce the same result. Only data that is not affected by the execution of the BAPI, for example, Customizing data, can be buffered. For BAPIs this means, for example, that due to transparency, Set and Get parameters and the global memory should not be used. However, you can keep Customizing data in a global memory as this data remains unchanged even if transaction calls are repeated.

•

All or nothing principle A database change, for example, creating a new sales order, must be carried out completely or not at all (LUW). This is why BAPIs to be implemented in 3.1 are created with integrated commit control. The COMMIT WORK command is always invoked at the end of the function module of a BAPI that modifies data.

If a BAPI executes a COMMIT WORK command, this must be mentioned in the BAPI documentation. This is the only way users are able to know that the BAPI contains a COMMIT WORK command.

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BAPI Transaction Model with Commit In later releases BAPIs can only be implemented with integrated COMMIT WORK commands in exceptional cases. BAPIs with COMMIT WORK must be documented in the SAPNet - R/3 Frontend in Note 0131838, "Collective Note for BAPIs with the Commit Work Command". •

No functional dependency between two BAPIs A BAPI call must not be negatively affected by an earlier call of another BAPI. A follow up call must not presuppose an earlier call. For this reason also, you should not use Set and Get parameters in the BAPI nor use the global memory. Make sure that a COMMIT WORK command only deletes the memory of the function module, and not the memory of the function group. The global data of the function group remains and could prevent another BAPI from being called, and thus impair the BAPI’s functional independence.

•

Other separate LUWs are not triggered The call of a BAPI must not trigger further LUWs that are independent of the BAPI. For this reason BAPIs must not contain the following commands:

•

CALL TRANSACTION

•

SUBMIT REPORT

•

SUBMIT REPORT AND RETURN

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BAPI Programming BAPI Transaction Model Without Commit

BAPI Transaction Model Without Commit Use As of Release 4.0 the commit control must be taken out of write BAPIs, that is, those BAPIs that cause database changes. The existing transaction model should not be changed. This is achieved by using the method TransactionCommit of the business object type BapiService which executes the command COMMIT WORK. The process flow of the program consists of the following steps (see graphic below): Log on ... Source code * Call BAPI Source code * Call BAPI Source code Call BAPI BapiService.TransactionCommit() ... Source code * Call BAPI Source code * Call BAPI …. Source code Call BAPI BapiService.TransactionCommit() ... Source code Log off

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BAPI Transaction Model Without Commit

BAPI Transaction Model Without Commit

BAPI call

Visual Basic

...

BAPI call

...

BAPIService Transaction Commit call

...

R/3(ABAP)

...

...

Commit Work

Log on

Log off Logical Unit of Work

RFC Session

The same rules apply in this model as in the BAPI Transaction Model With Commit [Page 60]. But also keep in mind: •

If a termination message is displayed (message type A) in the Return parameter, a database rollback can be executed by the BAPI. This causes all the activities carried out since the last COMMIT WORK command to be canceled. This situation must be described in the Return parameter documentation for the BAPI in question.

•

Operations that change the database must be carried out through the updating process.

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BAPI Programming Customer Enhancement Concept for BAPIs

Customer Enhancement Concept for BAPIs Use The customer enhancement concept for BAPIs enables customers to enhance business object types without modifications, for example, make table enhancements to master data, and then to reflect these enhancements in the BAPIs of the business object types.

The customer concept described here has been introduced in Release 4.5B. Customer exits implemented using the enhancement concept valid before do not have to be reprogrammed. The customer enhancement concept is converted in the BAP interface by standardized extension parameters which can be combined with one or both of the enhancement mechanisms below: •

By the BAPI table extensions developed by BAPI programmers. Customers must not program these extensions.

•

Conventional customer exits that can be individually implemented.

The customer enhancement concept is not intended for developing individual industry solutions within SAP; a special enhancement concept has been defined for industry solutions. For further information contact the BAPI Development.

Features Extension Parameters in BAPI Interfaces First consider which tables used by the BAPI may be suitable for customer enhancements. Then, depending on the requirements of the BAPI, create, one extension parameter for the data import and/or one extension parameter for the data export. Note the following guidelines: •

The naming convention for the extension parameter is ExtensionIn for import parameter enhancements and ExtensionOut for export parameter enhancements.

•

Define the extension parameter as a table parameter.

•

Use the reference structure BAPIPAREX for extension parameters. With this structure the extension parameter can be used as a generic data container.

Extension parameters can relate to BAPI table extensions and/or to customer exits already in the program (see below). We recommend you use BAPI table extensions, if possible, because customer enhancements can be automatically used by the BAPI and do not require customers to rewrite any programs. You should create customer exits to enable customers to enhance BAPI interfaces in situations where it was not anticipated enhancements may be needed.

BAPI Table Extensions BAPI table extensions and help structures are used to copy data from a customer table extension and to place it in an extension parameter. Customer-defined data can then be read and processed by the BAPI automatically.

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Customer Enhancement Concept for BAPIs BAPI table extensions can only refer to tables whose contents belong to the business object type. For example, the Create() BAPI of the business object type Material, cannot have a BAPI table extension that supports a table extension of the business object type Equipment. The graphic below shows how extension parameters and BAPI table extensions function together: The BAPI TravelAgency.CreateFromData has a standardized parameter ExtensionIn for extending the import parameter to be read. The parameter ExtensionIn relates to the BAPI table extension BAPI_TE_STRAVELAG. This consists of: •

A key part predefined by SAP (AGENCYNUM). The key field of the database table STRAVELAG which the BAPI table extension refers to.

•

Data part (CUSTOMER FIELD1 to CUSTOMER FIELD3) determined by the customer in an append technique . These are the fields with which the customer extended table STRAVELAG. BAPI: TravelAgency.CreateFromData BAPI Table Extension: BAPI_TE_STRAVELAG

Parameter: AgencyDataIn

Felder AGENCYNUM .APPEND CUSTOMER FIELD _1 CUSTOMER FIELD _2 CUSTOMER FIELD _3

AgencyNumber Return ExtensionIn Fields from ExtensionIn: Structure

BAPI_TE_ STRAVEL AG

… …

Valuepart1

Valuepart2

Valuepart3

Valuepart4

Values from CUSTOMER FIELD_1, CUSTOMER FIELD _2, CUSTOMER FIELD _3

Database table: STRAVELAG Key field AGENCYNUM Fields NAME STREET ... ... TELEPHONE URL LANGU .APPEND CUSTOMER FIELD _1 CUSTOMER FIELD _2 CUSTOMER FIELD _3

Customer-defined fields are able to be automatically processed because the use of BAPI table extensions are searched for in the ExtensionIn parameter in the BAPI program code. The name of the active BAPI table extension (here BAPI_TE_STRAVELAG) is inserted in the STRUCTURE field of the ExtensionIn parameter. The key of the extended table (AGENCYNUM) and the customer-defined data part (CUSTOMER FIELD1 to CUSTOMER FIELD3) are transferred to the data fields VALUEPART1 to VALUEPART4 in the extension parameter. If the fields inserted by a customer in a BAPI table extension exactly match the fields in the table extended by the customer, the BAPI can read or write the data using 'move-corresponding'. As shown by the arrows and color in the graphic, specific guidelines and naming conventions must be followed for the implementation and when using extension parameters with BAPI table extensions, to assure that customer data can be processed without errors occurring. When creating BAPI table extensions, make sure you:

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BAPI Programming Customer Enhancement Concept for BAPIs

•

Create one BAPI table extension for each table to be extended.

•

The naming convention for BAPI table extensions is BAPI_TE_.

The BAPI table extension BAPI_TE_MARA relates to table MARA. •

The structure of the BAPI table extension must contain the key fields of the table that the BAPI table extension relates to.

The BAPI table extension BAPI_TE_MARA has a field MATNR, as MATNR is the key field of table MARA. •

Customers can use only fields of data type CHAR and similar data types in BAPI table extensions. This restriction is due to the reference structure BAPIPAREX of the extension paramters. Customers cannot use fields from the standard table in the append of the BAPI table extension because a 'move corresponding' would overwrite the SAP field. For further information see the Customer Enhancement Concept [Ext.] in the BAPI User Guide.

•

A BAPI table extension can have a maximum length of 960 characters.

•

All available BAPI table extensions must be listed in the documentation on the extension parameter.

Programming examples are provided in the function modules BAPI_TRAVELAGENCY_CREATE and BAPI_TRAVELAGENCY_GETDETAIL. The methods are called TravelAgency.CreateFromData() and TravelAgency.GetDetail(). The extract below from the program code for the BAPI TravelAgency.CreateFromData shows how the ExtensionIn parameter and the BAPI table extension are used. loop at extensionin. case extensionin-structure. when 'BAPI_TE_STRAVELAG'. move extensionin+c_lenstruc to wa_bapi_te_stravelag. move agencynumber to wa_bapi_te_stravelag-agencynum. read table t_stravelag with key agencynum = agencynumber. catch system-exceptions conversion_errors

= 1.

move-corresponding wa_bapi_te_stravelag to t_stravelag. endcatch.

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Customer Enhancement Concept for BAPIs

Customer Exits If BAPI table extensions cannot be used, you should insert customer exits in suitable places in the source code of the BAPI, to enable customers to program their own exits and to include them in the BAPI. The standard rules for customer exits apply and maintenance with Transaction SMOD (SAP internal) and CMOD (for customers). For further information see the documentation on SAP Enhancement Management (for Transaction SMOD) and in BC - Enhancing the SAP Standard [Ext.] (for Transaction CMOD). Note the following: •

BAPIs that cause database changes, e.g. Create(), Change() Create a customer exit that checks all the data and transfers data to internal, customerdefined structures. A second customer exit must be provided for writing data to customer-defined tables.

•

BAPIs with read function, for example GetDetail() Create a customer exit after the SAP data retrieval to enable customers to then import their own data.

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BAPI Programming Internal and External Data Formats

Internal and External Data Formats Use BAPIs are not end user interfaces, they are programming interfaces that can be used in diverse application areas, for instance, to connect non-SAP systems and PC products to the R/3 System. To meet the requirements of this diverse range of applications, a common strategy for representing data in the BAPI interface must be used.

General Guidelines Fields in BAPI parameters must be presented in the internal form used in the database and not in a form formatted in the BAPI interface. Because of the reasons above, BAPIs should not convert data between the internal and external data formats, except in the circumstances outlined below. For example, the date in a BAPI must be in the format used internally, YYYYMMDD, where YYYY is the year, MM the month and DD the day. The graphic below shows the BAPI programming interface where data is transferred at the source code level and not at the application interface level.

BAPI Programming Interface

GUI

Application program

GUI

BAPI

Application program

External data format, for example, on the screen (GUI)

Internal data format

Exceptions There are exceptions where the calling program has to map and convert the data between the internal and external data formats in a BAPI.

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BAPI Programming Interface For these exceptions you can generate function modules that can map and, if required, convert between the internal and external data formats. The section Converting Between Internal and External Data Formats [Page 140] describes how to generate these function modules. You can use these function modules in the source code of your BAPI for the following: •

To map the internal work structures to the external BAPI structures before calling the BAPI

•

To map the result to the internal work structure after the BAPI has been called

•

To map the imported parameters to the internal structures (import parameter structures) when you are implementing the BAPI

•

To map the result from the internal structure to the BAPI (export parameter structures) when you are implementing the BAPI

These exceptions are: •

Currency amount fields In an R/3 System a currency amount field can only be used when accompanied by a currency code. Only then can the decimal point be set correctly. A currency code field must be assigned to each currency amount field. For example, two yen are stored as 0.02 in the field of data type CURR in the database. Non-SAP systems will not understand this syntax. All R/3 currency data types have two digits after the decimal point, even though currencies do exist with three digits after the decimal point. For these reasons, the data type CURR cannot be used in the BAPI interface. Adhere to the following guidelines when using currency amount fields in BAPIs: −

You must not use parameters and fields of data type CURR in the interface

−

All parameters and fields for currency amounts must use the domain BAPICURR with the data element BAPICURR_D or BAPICUREXT with the data element BAPICUREXT.

−

The position of the decimal point in currency amount fields must be converted correctly You can use two function modules for this conversion. The function module BAPI_CURRENCY_CONV_TO_EXTERNAL converts currency amounts from R/3 internal data formats into external data formats. The function module BAPI_CURRENCY_CONV_TO_INTERNAL converts currency amounts from external data formats into internal data formats.

•

Quantity Fields and Unit of Measurement Fields Like currency amount fields, the decimal point in quantity fields and unit of measurement fields must be converted correctly. A field to indicate the amount or the unit of measure must be assigned to all amount and quantity fields. Quantity fields have no standard domain that can be used for BAPI structures.

•

Internal keys In some situations an internal technical key is maintained in the database alongside the external key. Examples are work breakdown structure plans or networks in project systems.

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BAPI Programming BAPI Programming Interface

You must always use the external key in the BAPI interface. To convert activity codes in networks, the following function modules are provided: −

EXT_ACTIVITY_GET_INT_ACTIVITY, to convert from the external activity into the internal activity

−

INT_ACTIVITY_GET_EXT_ACTIVITY, to convert from the internal activity into the external activity.

These conversion transactions are not included in the transactions described in the section Converting Between Internal and External Data Formats [Page 140]. •

ISO codes In R/3 Systems ISO codes are currently supported for language, country, currency, and unit of measure fields. If you use one or more of these fields in your BAPI you have to make two fields available for each of these fields in the BAPI interface: one field containing the SAP code and another containing its corresponding ISO code. Use the naming convention, Fieldname_for_SAPCode_ISO for the field containing the ISO code. For example, the field LANGU contains the country codes used internally in R/3, for instance E. The corresponding field for the ISO code would then be named LANGU_ISO and would contain the corresponding ISO code EN. Implement the BAPI as follows: −

When you export data from the BAPI both fields must contain corresponding values.

−

When you import data into the BAPI the ISO code is only significant if no value was given in the SAP code.

Use the domains below for the ISO codes:

Domains for SAP internal codes and ISO codes Size

ISO Code Domain

SAP Code Domain

Currency key

ISOCD

WAERS

Quantity unit

ISOCD_UNIT

MEINS

Language key

LAISO

SPRAS

Country key

INTCA

LAND1

For every domain there is a data element of the same name. •

Dates and Time In accordance with ISO standard 8601 dates an time must be transferred between two external systems in Universal Coordinated Time (UTC). UTC is the equivalent of the formerly used term GMT (Greenwich Mean Time) and is now used as the unique time reference across the globe. In the BAPI interface you have to provide a field for the time zone, that is, the location of an object with respect to its local time, as well as a field for the UTC time stamp. You can also specify the local time. The naming convention for the UTC time stamp field is _ISO.

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BAPI Programming Interface The following types are provided for dates and time.

•

−

TIMESTAMP

−

TIMEZONE

Specific fields in address structures These fields are:

•

Address text (fields TITLE_P, TITLE and FORMOFADDRESS)

•

Academic title (fields TITLE_ACA1 and TITLE_ACA2)

•

Name prefixes, for example "von", "van der" (fields PREFIX1 and PREFIX2)

•

Names affixes, for example, titles (field TITLE_SPPL) For more information see Address Parameters [Page 123].

BAPIs for Converting Between Internal and External Data Formats (Converting Domains) BAPIs are programming interfaces in which, with a few exceptions, only the internal data format should be used. However, application programmers calling a BAPI from within their program may sometimes require the external format, for example, to display data on the screen. In such cases the calling program must be able to convert between the internal and external data formats. The calling program can use conversion BAPIs to convert data into the required format: These are described in the BAPI User Guide in the section Service BAPIs for General BAPI Functions [Ext.].

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BAPI Programming Providing Input Help (F4 Help)

Providing Input Help (F4 Help) Use Users of R/3 Systems can use the F4 key to retrieve information about the possible input values for screen fields. Information about the possible values for a field should also be available to those users who are working with the data in the R/3 System from an external program, via BAPI calls. For example, the user of a Visual Basic program which incorporates a BAPI to display or modify data in R/3 should have transparent access to the functionality of the F4 input help.

Features In order to provide input help, a calling program can use the BAPI HelpValues.GetList(). This method is based on the RFC-enabled function module BAPI_HELPVALUES_GET, which obtains the possible input values for a field that is passed in a BAPI call. Detailed information about the structure and use of the BAPI HelpValues.GetList() is available in the documentation for this BAPI. The BAPI HelpValues.GetList() method refers to the help view for the check table, matchcodes or domain fixed values linked to the field in the ABAP Dictionary. For this reason, you have to create or specify relevant check tables, match codes or domain fixed values. Only then can the calling program access the relevant input values for your BAPI fields using the BAPI HelpValues.GetList().

As of Release 4.5A you have to specify a foreign key, if a check table has been defined in the domain. Otherwise F4 input help cannot be displayed. For information about check tables, matchcodes and domain fixed values see the ABAP Dictionary [Ext.].

Authorization Check In some cases you will only want to allow only those persons with a specific user profile to access information in F4 input help. To do this you can carry out authorization checks within the BAPI using table BAPIF4T. This table comprises the following fields which you have to fill with the values for your BAPI. •

OBJTYPE (object type) The technical name of the SAP business object type, for example, BUS1065.

•

METHOD (verb) The name of a BAPI for the business object type named above, for example, GetList.

•

DTEL (data element) The name of a data element for which a possible entry is specified. For example, an elementary input help could be specified for the data element PERNR_D and be protected from unauthorized access.

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Use •

FNAM (name of the function module) The name of the function module that you have to create and that carries out the authorization check for the data element. This function module must have the following predefined interface: *"------------------------------------------------------*"*"Local interface: *" IMPORTING *" VALUE(OBJTYPE) LIKE BAPIF4F-OBJTYPE *" VALUE(METHOD) LIKE BAPIF4F-METHOD *" VALUE(DTEL) LIKE BAPIF4F-DTEL *" VALUE(SHLPNAME) LIKE BAPIF4F-SHLPNAME *" VALUE(TABNAME) LIKE BAPIF4F-TABNAME *" EXPORTING *" VALUE(RETURN) LIKE BAPIF4F-RETURN *"---------------------------------------------------------

As the template for your function module you can use the function module BF_BAPI_F4_AUTHORITY which provides exactly this interface. Copy this function module and follow the documentation provided with it. The additional parameter SHLPNAME contained in the function module interface provides the name of the active input help for the table or for the data element. The parameter TABNAME contains the name of the value table. The return code of the parameter RETURN is: −

'X' if the user of the BAPI is not authorized to call up the valid input values for a field.

−

' ' (no value), if the user of the BAPI is authorized to display the input values for a field. During runtime the function module is called dynamically by the BAPI HelpValues.GetList(). An authorization check can be carried out at business object type, method or data element level:

To carry out authorization check at this level....... Business object type BAPI Data Element

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... ......the following fields in table BAPIF4T must be filled. OBJTYPE, FNAM OBJTYPE, METHOD, FNAM OBJTYPE, METHOD, DTEL, FNAM

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BAPI Programming Providing Interface Descriptions

Providing Interface Descriptions Use Descriptive text, for example, short texts and texts on how to write help functions are very useful for using BAPI interfaces. Various functions are provided that support R/3 users in carrying out the tasks required of them. For example, F1 help provides information on specific input fields. F1 help should also be available to users who are working with data in an R/3 System from an external program, via BAPI calls.

Features Service BAPIs are provided that are used by external programs to call documentation and descriptions of BAPI interfaces. •

BapiService.FieldHelpGetDocu() This method reads the documentation (F1 help) for the fields in a BAPI parameter. Application developers can use this method to provide end-users with descriptions of fields in a BAPI parameter. To ensure that F1 help for your BAPI can be called via the method BapiService.FieldHelpGetDocu(), data element documentation must be written for each parameter field in the BAPI.

•

BapiService.InterfaceGetDocu() This method reads the whole interface documentation for a BAPI. You can use this method to access the documentation on the business object type, method, parameters and parameter fields. To support application developers with their work, the documentation on BAPI interfaces must be complete. For internal use SAP provides detailed guidelines on writing BAPI documentation. You can get a copy of the guidelines from your contact person in the BAPI Development group. See the general Documentation Guidelines [Page 88].

•

BapiService.MessageGetDetail() This method returns the short and long texts of BAPI error messages. To enable application developers to process BAPI error messages, you have to maintain the short and long error texts for the BAPI. You should follow the standard ABAP programming rules.

For information about these BAPIs see the relevant BAPI documentation.

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Providing Interface Descriptions

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BAPI Programming Buffering with Write BAPIs

Buffering with Write BAPIs Use To save external systems each having to define their own data, predefined buffering mechanisms should be implemented in all write BAPIs (i.e. BAPIs that create and change data). For SAP internal use this is particularly relevant for BAPIs developed as of Release 4.6A. If you want to implement a buffer for BAPIs in an earlier release, you should first contact a colleague in the central BAPI development group. For BAPIs standard R/3 System mechanisms can be used to buffer application data. Data to be created or changed by a BAPI is not created in the update buffer, it is first collected in the global buffer of the BAPI function module group. Then the whole buffer is updated at a specified time. This has the following advantages: •

Improvement in performance of the whole system. The updating of individual operations is delayed and they can all be updated together. Techniques such as "array insert" improve system performance. If buffering is not used, each change must be updated separately.

•

Several changes to an application instance With the first change the data is read from the database into the buffer and the change is made in the buffer. With the next change, the system recognizes that the data already exists in the buffer and also makes the change in the buffer. If buffering is not used, the first change would have to be updated before a second change could be made.

•

Using in Application Link Enabling BAPIs with buffering are especially suited in situations where mass data is exchanged between systems via Application Link Enabling (ALE). The buffering mechanism enables application instances to be processed separately in the ALE layer, while still enabling the instances to be updated together. Unlike multiple BAPIs, such as, SaveReplicaMultiple(), this procedure allows error handling of individual instances.

BAPIs with buffering mean that there is no need to use or implement multiple BAPIs.

Integration The Transaction Model for BAPIs Without Commit [Page 63] in use since Release 4.0 can be enhanced on the basis of these advantages: •

Within one Logical Unit of Work (LUW) several changes or detailed changes can be carried out for one instance.

•

All changes (to one or more instances) are updated together by the BAPI BapiService.TransactionCommit().

This graphic shows the transaction model for BAPIs without buffering:

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Buffering with Write BAPIs

Transaction Model Without Buffering Create i1

BapiService.TransactionCommit Create i2 Change i1 BapiService.TransactionCommit

Client (e.g. Visual Basic)

Server (R/3)

i1 is passed to pdate

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LUW

i2 passed to update

Update performed: i1 and i2 are updated separately

LUW

i1 passed to update

Update performed: i1 updated

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BAPI Programming Buffering with Write BAPIs

This graphic shows the transaction model for BAPIs with buffering:

Transaction Model with Buffering Create i1 Change i1 Create i2 BapiService.TransactionCommit Client (z.B. Visual Basic)

Server (R/3)

LUW

Instances are created and processed in the buffer

Buffer contents passed to update. Update is performed: i1 and i2 are updated together

Prerequisites The buffering mechanism for BAPIs must be implicit, that is, the caller must not have to control the buffering. A calling program must be able to use, for example, a Create()or Change() BAPI with buffering as well as it can use a BAPI without buffering. The buffer is updated implicitly in R/3. If buffering has been implemented for a business object type, all write BAPIs of this business object type must also be implemented with buffering. If write BAPIs with buffering have been implemented for a business object type, this affects the read BAPIs of this object type. Refer to the information in the Activities section below.

Features For BAPIs with buffering, in addition to the standard guidelines, the following implementation steps and characteristics described below are required.

Function Modules for Updating the Contents of the Buffer As BAPIs with buffering can only create or change instances in the buffer, you have to provide one or more function modules to carry out the final update of the buffer contents. These update modules transfer the entire contents of the buffer to the update program. These function modules should not be implemented as BAPIs, as these are only used in the system in which the buffer is also used.

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Buffering with Write BAPIs The naming convention for these function modules is: _SAVEBUFFER. Exceptions must not be defined for the update modules, as these are not run until the end of the program, when error handling is no longer possible (see Special Characteristics below).

Function Modules for Deleting the Contents of the Buffer To ensure that the buffer is empty at the start of a transaction, you must provide a function module that deletes the contents of the buffer. This delete function module deletes the entire contents of the buffer and removes any locks on the instances. Neither should you implement this function module as a BAPI, because it is only used in the system in which the buffer is also used. The naming convention for this function module is: _CLEARBUFFER. No exceptions can be defined for delete modules because these are not run until the end of the transaction, when error handling is no longer possible (see Special Characteristics below).

Special Characteristics BAPIs with buffering need to have special characteristics. For example, these BAPIs must be able to deal with errors because a caller cannot reprocess data in the buffer. As data is buffered implicitly, no administration BAPIs are provided for callers.

Consistency of the Buffer Contents A BAPI with buffering must carry out all the processing steps, except for updating. The consistency of all instances created or changed in the buffer must be guaranteed by the application. This means that: •

Only operations that can be updated with consistency guaranteed can be carried out in the buffer. The update module itself cannot perform consistency checks.

•

All other steps required before updating, such as assigning numbers or creating application blocks, must be carried out before calling the update module.

•

For operations that cannot be updated consistently, no action can take place. In these cases the error situation must be reported in the BAPI return parameter.

Calling Update Modules After the buffer operations have been successfully carried out, using the command PERFORM ON COMMIT call a form routine which then calls the update module(s). The update modules must be called using the command CALL _SAVEBUFFER IN UPDATE TASK to flag the execution in the update program. By adding 'ON COMMIT' to the command PERFORM ON COMMIT, updating is not carried out immediately,it is carried out in the next COMMIT WORK. This way any number of BAPI calls can be collected together. The final COMMIT WORK command that is executed via the BAPI BapiService.TransactionCommit(), executes the form routine and also each update

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BAPI Programming Buffering with Write BAPIs

module once only. For this reason error handling cannot be performed in this form routine nor in the function module.

Subscribing the Delete Module At the start of each LUW the buffer must be empty. Any instances that may exist in the buffer, which were updated in an earlier LUW, are no longer blocked and may be older than the versions in the database. If this instance is updated again, inconsistencies would result. At the end of each LUW, the buffer contents must be deleted by calling the delete module. This can only be done by the BAPIs BapiService.TransactionCommit() and BapiService.TransactionRollback(). To supply these BAPIs with the necesary information, BAPIs with buffering must subscribe thier delete module for the BAPI BapiService.TransactionCommit() bzw. BapiService.TransactionRollback(). The delete module is subscribed by calling the central function module BUFFER_SUBSCRIBE_FOR_REFRESH, whereby the parameter NAME_OF_DELETEFUNC must contain the name of the delete module.

No COMMIT WORK or ROLLBACK WORK Command BAPIs with buffering must not execute COMMIT WORK or ROLLBACK WORK commands.

Documentation Each BAPI with buffering must be explicitly documented as such.

Activities Keep in mind the following important information about how write BAPIs with buffering interact with read BAPIs of the same business object.

Write BAPIs with Buffering and Read BAPIs for the Same Business Object No Buffering for Read BAPIs If write BAPIs with buffering are implemented for the same business object type, read BAPIs are not allowed to use the buffer for the same business object type, so that data read from the database can be stored, thereby avoiding further database accesses. As the imported data is not locked, the corresponding data in the buffer would become outdated over time. Subsequent read operations would first access the buffer and read the potentially outof-date data, as data in the database can only be read, if this data is not in the buffer.

Buffer Instances Are "Real" Instances All instances created or changed by write BAPIs in the buffer are consistent. They can be used by other change BAPIs for further processing within the same LUW. To guarantee the consistent behavior, all read BAPIs must handle existing instances that are in the buffer, and not yet in the database, as valid instances. Read BAPIs must be implemented in such a way that they first try to read an instance in the buffer and only start searching the database, if the instance is not found in the buffer. A buffer instance is therefore "real" instance. For example, a BAPI ExistenceCheck() must search for the existience of an instance in the buffer also.

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Documenting Read BAPIs Each read BAPI that handles the buffering of corresponding write methods must be documented.

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BAPI Programming Example of Implementation and Process Flow

Example of Implementation and Process Flow The example below describes the implementation and process flow of BAPIs with buffering. A more detailed example is the BOR is the BAPI CreateFromData() of business object type TravelAgency (SAGENCY. The development class is SAPBC_BOR.

Implementation For the business object , BAPIs with buffering should be provided, in particular Create() and Change() BAPIs. In the BAPI function group , belonging to the business object, the following routines or function modules are created. •

Form routine for the update form . call _savebuffer in update task. endform.

•

Update module function _savebuffer. ... {Read buffer} {Update buffer} ... endfunction.

•

Delete module function _clearbuffer. ... {Update buffer} ... endfunction.

•

Function module for the Create() BAPI function bapi__create. call buffer_subscribe_for_refresh exporting name_of_deletefunc = _clearbuffer. {Operations in buffer} perform on commit. endfunction.

•

Function module for the Change() BAPI

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Example of Implementation and Process Flow function bapi__change. call buffer_subscribe_for_refresh exporting name_of_deletefunc = _clearbuffer. {Operations in buffer} perform on commit. endfunction.

Process Flow An external application executes the BAPI Create() of business object twice, to create the two instances 4711 and 4712. Then another change is made to instance 4711 using the BAPI Change(). To complete the LUW, the BAPI BapiService.TransactionCommit() is executed. The steps are: Step

Process Flow

1. Call meth od .C reate( ) for insta nce 4711

The delete module _clearbuffer is subscribed by calling buffer_subscribe_for_refresh for the BAPI BapiService.TransactionCommit().

2. Call meth od .C reate( ) for insta nce 4712 3. Call meth od Chan ge() for insta nce 4711

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The buffer is empty. Instance 4711 is created in the buffer. The call of the update module is _savebuffer is flagged using the form routine .

The delete module _clearbuffer is subscribed by calling the buffer_subscribe_for_refresh for BAPI BapiService.TransactionCommit(). As this is already subscribed, it is not subscribed again. Instance 4712 does not yet exist in the buffer; it is created here. The call of the update module is _savebuffer is flagged using the form routine . As this is already flagged, it is not flagged again.

The delete module _clearbuffer is subscribed by calling the buffer buffer_subscribe_for_refresh for BAPI BapiService.TransactionCommit(). As this is already subscribed, it is not subscribed again. Instance 4711 exists in the buffer; it is changed here.

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BAPI Programming Example of Implementation and Process Flow

The call of the update module is _savebuffer is flagged using the form routine . As this is already flagged, it is not flagged again. 4. Call meth od Bapi Servi ce.Tr ansa ction Com mit()

The form routine of the function group is executed once only by the COMMIT WORK command. This executes the update module and the contents of the buffer is transferred to the update program. After the COMMIT WORK command, the delete modules subscribed for the BAPI BapiService.TransactionCommit() are called, that is, the function module _clearbuffer is executed and the buffer for the business object is emptied.

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Improving Performance

Improving Performance Use In order to improve the performance of your BAPI, you should follow the standard ABAP programming guidelines: •

Use only complete WHERE conditions to minimize the amount of data to be transferred.

•

Avoid unnecessary database access.

•

Do use of arrays.

•

Buffer data, for example in the local memory of the function module. Note that you must not buffer data in the global memory.

•

The locking granularity must correspond to the instance granularity in the object model.

•

Do not generate programs at runtime.

See the internal SAPnet for further notes about effective programming in the R/3 environment.

Additional Guidelines for BAPI Programming The function module on which a BAPI is based can be accessed by external programs using RFC. For this reason, you should follow these additional guidelines when programming BAPIs: •

Large amounts of data Mass data is treated differently in ABAP programs, which use the SAPgui (graphical user interface) as a front end, and in programs developed on external development platforms such as Visual Basic. If large amounts of data are read in the R/3 System, for example a list containing many entries, the majority of the data remains on the application server. Only the data that is actually displayed is sent to the front end. In contrast, if you are programming with Visual Basic, all the data will be sent from the application server to the client system. This increases the load on the network and the amount of memory required in the client system. You need to cover the situation when your BAPI has to read mass data. For example, you could specify a limit so that only the first n data records are read. Alternatively your BAPI could return a message to the calling program indicating that the amount of data has exceeded a certain limit and that a new selection should be made.

•

Do not define parallel processes.

•

If no COMMIT WORK is triggered after a BAPI is called, a lock that has been set has to be explicitly deleted.

•

To reduce the duration of database locks, you should not assign numbers to them individually. Instead make use of the buffers. Read the numbers to a buffer and assign the numbers directly from the buffer.

•

Lock periods can be minimized by making database updates as close as possible to the COMMIT WORK command. This reduces the duration of database locks and the risk of blocking other processes.

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BAPI Programming Improving Performance

•

The less specific the (partial) key of a modified data record is, the more likely it is that the data record will be accessed by multiple BAPIs, causing the record to be locked. For example, running a statistic on plant level will have a negative impact on the performance of the BAPI, whereas a statistic based on plant and material will cause fewer locks because it will apply to fewer BAPIs.

•

Minimize the use of read transactions which depend on a previous database COMMIT (committed read). These read transactions have to wait for the COMMIT WORK command of the update transaction to be processed.

•

All tables that are not protected by SAP internal locks must always be updated in the same order to prevent a deadlock.

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Documentation Guidelines

Documentation Guidelines Purpose To use a BAPI in an application program, application developers need to know: •

Which BAPI provides the required data, that is, they need to know what the BAPI can do.

•

How the BAPI is called, that is what are the parameters and fields of the BAPI interface.

Application developers access the technical meta data and documentation of BAPIs from the Business Object Repository. This section contains general guidelines for documenting BAPIs. For internal use, SAP provides detailed guidelines on writing BAPI documentation. You can get a copy of the guidelines from your contact person in the BAPI Development group.

Prerequisites BAPIs are business interfaces to the R/3 System and users are not required to have a thorough knowledge of the R/3 System and the R/3 development environment. Readers of BAPI documentation are often not R/3 experts or business application experts.

Process Flow To give application developers a complete picture of the functionality of a BAPI, the following documentation must be provided:

Documentation on Methods Create this documentation in the Function Builder in the function module that the BAPI is based on. The purpose of this documentation is to explain what the method does and how the communication with external programs works. The documentation should help customers decide whether a method is appropriate to perform the task in question and it should therefore provide answers to the following questions: •

What is the business function of the BAPI and what can it be used for?

•

What exactly are the functions of the BAPI?

•

Are there any important limitations, that is, functions that this BAPI cannot perform?

•

What must you pay particular attention to with this BAPI? For example, is special authorization required to use this BAPI?

•

Are there any Customizing dependencies?

•

What dependencies are there between this BAPI and other BAPIs, and between individual method parameters?

If the BAPI uses a COMMIT WORK command or works with buffering, you must include this in the documentation.

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BAPI Programming Documentation Guidelines

Documentation on Method Parameters Documentation on the individual parameters is also written in the Function Builder in the associated function module. Parameter documentation should provide answers to the following questions: •

What is the parameter used for?

•

Which fields must be filled, that is, what are the mandatory fields?

•

What are the dependencies between fields?

•

Are there any fixed values and what do they do?

•

What are the default values of the parameter? All the fields that are assigned default values by Customizing and are therefore write-protected, must be documented.

•

Which return codes may be returned to the calling program directly or indirectly in the Return parameter?

Data Element Documentation on Parameter Fields A calling program can call data element documentation (F1 help) for a field in a BAPI parameter using the Service BAPI BapiService.FieldHelpGetDocu (see Providing Input Help [Page 73]). For this reason you have to write data element documentation for each field in BAPI parameters.

Further Documentation To provide the complete context of a BAPI, the information below must also be available: •

Documentation on the business object type the BAPI is implemented for.

•

Documentation on the key fields of the business object type.

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Programming Standardized BAPIs

Programming Standardized BAPIs Purpose Some BAPIs and methods provide basic functions and can be used for most SAP business object types. These BAPIs are called “standardized” BAPIs.

Process Flow If your BAPI is a standardized BAPI, you should implement it following the programming guidelines described in the following sections.

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BAPI Programming Programming GetList() BAPIs

Programming GetList() BAPIs Use With the BAPI GetList() you can select a range of object key values, for example, company codes and material numbers. The key values returned by this BAPI can be passed on to another BAPI for further processing, for example, the BAPI GetDetail(). The BAPIs GetList() is a class method (instance-independent).

Features Provide all the relevant fields in the interface of the GetList() BAPI. How complex and extensive you structure the interface, depends on the requirements the BAPI is to fulfill.

Import Parameters The interface of a GetList() BAPI must provide selection parameters, in which the required selection criteria can be passed on by the calling program. The structure of selection parameters is described in the section Selection Parameters [Page 134]. You must also create the parameter MaxRows that enabes you to limit the number of entries selected. This parameter prevents too large a value set from being selected, if the selection parameter specification is not very precise. Use the data element BAPIMAXROW as the reference type for the MaxRows parameter.

Export Parameters The key values selected by the BAPI GetList() are returned to the calling program in a table, together with other useful information, for example, short texts. To report messages from the method call back to the calling program, you should create the export parameter RETURN. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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Example of a GetList() BAPI

Example of a GetList() BAPI The BAPI GetList of the business object type CostCenter (BUS0012) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Programming GetDetail() BAPIs

Programming GetDetail() BAPIs Use The BAPI GetDetail() is used to read details of specific object instances. The BAPI GetDetail() is an instance method.

Features Import Parameters The import parameters of the GetDetail() BAPI must contain the key fields of the business object type. For the associated method definition in the BOR, the key fields must not also be specified as method parameters. For this reason, the BOR/BAPI Wizard does not include the function module parameters for the key fields in the method definition, when it creates a BAPI.

Export Parameters The export parameters of a BAPI contain details of the instance. According to the amount of information, this should be structured in several parameters with meaningful names. To report messages from the method call back to the calling program, you should create the export parameter Return. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension Parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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Example of a GetDetail() BAPI

Example of a GetDetail() BAPI The BAPI GetDetail() of the business object type CompanyCode (BUS0002) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Example of a GetDetail() BAPI

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Programming GetStatus() BAPIs

Programming GetStatus() BAPIs Use With the BAPI GetStatus() you can retrieve information about the status of a particular object instance. The BAPI GetStatus() is an instance method.

Features Import Parameters The import parameters of the GetStatus() BAPI must contain the key fields of the business object type. For the associated method definition in the BOR, the key fields must not also be specified as parameters. For this reason, the BOR/BAPI Wizard does not include the function module parameters for the key fields in the method definition, when it creates a BAPI.

Export Parameters The export parameters of the BAPI contain information about the status of an object instance. To report messages from the method call back to the calling program, you should create the export parameter RETURN. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension Parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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BAPI Programming Example of a GetStatus() BAPI

Example of a GetStatus() BAPI The BAPI GetStatus() of the business object type DebtorCreditAccount (BUS1010) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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Programming ExistenceCheck() BAPIs

Programming ExistenceCheck() BAPIs Use The BAPI ExistenceCheck() checks whether an entry exists in the database for an SAP business object type, for example, whether the customer master has been created. The ExistenceCheck() BAPI is an instance method.

Features You can implement this method as a BAPI and/or as a method of SAP Business Workflow. If you implement this method as a BAPI, it only has to be implemented once, because an ExistenceCheck() BAPI can also be used by SAP Business Workflow. To get the highest possible performance from the BAPI ExistenceCheck(), you should reduce the number of columns to as few as possible before selecting the table rows. select single bukrs from bkpf into lv_bukrs where bukrs = bkpf-bukrs and

belnr = bkpf-belnr

and

gjahr = bkpf-gjahr.

instead of select single * from bkpf where bukrs = bkpf-bukrs and

belnr = bkpf-belnr

and

gjahr = bkpf-gjahr.

Import Parameters The BAPI’s import parameters in the function module only contain the key fields of the business object type.

Export Parameters To report messages from the method call back to the calling program, you should create only the export parameter Return . For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Activities When a business object type is created, as the default, it inherits a definition of the method ExistenceCheck() through the interface IFSAP. For this reason, you can create an ExistenceCheck() BAPI using the BOR/BAPI Wizard, as the method name ExistenceCheck() already exists for the business object type. We recommend therefore, that you redefine the existing method ExistenceCheck() manually in the BOR, via the menu path Edit → Redefine. •

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Enter the function module that implements the ExistenceCheck() BAPI.

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BAPI Programming Programming ExistenceCheck() BAPIs

•

Create the method parameter RETURN (the key fields of the business object type are not included in the method definition in the BOR).

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Example of an ExistenceCheck() BAPI

Example of an ExistenceCheck() BAPI The BAPI ExistenceCheck() of the business object type CompanyCode (BUS0002) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Example of an ExistenceCheck() BAPI

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Programming Create() BAPIs

Programming Create() BAPIs Use The BAPI Create() creates one instance of an SAP business object type. Likewise, the BAPI CreateMultiple() creates several instances of a business object type simultaneously. If a workflow method called Create already exists for the business object type in question, you can use the name CreateFromData() for your BAPI. Create() is the preferred name for this BAPI. The BAPIs Create() and CreateMultiple() are class methods (instance-independent). For each Create() BAPI a method must be provided with which the created business object instance can be deleted or cancelled. To do this, depending on the business application practice, you should implement one of the BAPIs below: •

Delete(), which deletes a business object instance from the database. For more information see Programming Delete() BAPIs [Page 110].

•

Cancel() which cancels a business object instance. For more information see Programming Cancel() BAPIs [Page 113].

Features Import Parameters The BAPI’s import parameters in the function module contain the data required to uniquely identify an instance. For this you can either enter all object keys or else you must ensure that these can be derived. If required, you can also use a test run parameter to check the entry for an object instance before actually creating the instance in the database. For further information see Test Run Parameters [Page 135]. You can create a change parameter to identify the values to create the instance with and to tell differentiate these values from the initial values when the BAPI is called. We recommend that you identify the change-relevant fields by flagging them. For more information see Change Parameters [Page 125].

Export Parameters To make the object key available to the calling program, the entire key fields must be returned in the export parameters. To report messages from the method call back to the calling program, you should create the export parameter RETURN. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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BAPI Programming Programming Create() BAPIs

Avoiding Incompatibilities with Customizing Settings It could be possible that certain values set by Customizing appear differently in the BAPI interface. These values cannot be overwritten by a Create() BAPI. To avoid any incompatibility with Customizing settings, you should implement a Create() BAPI in the following way: •

The BAPI should transfer all the fields and check them against the Customizing settings. If the Customizing settings write-protect a field, the data in this field cannot be overwritten by data in the BAPI interface.

•

For every incidence of incompatibility an error message must be returned to the calling program. For example, “Customizing settings do not allow the field 'MyAsset-AssetName' to be modified ”.

•

All the fields that are assigned default values by Customizing and are therefore writeprotected, must be documented.

External Key Assignment For Create() BAPIs with an external key assignment the caller transfers the key (ID) to the object instance to be created, for example, to a document number. Keep in mind that you have to convert the specified keys explicitly in upper case letters in the source code of this type of Create() BAPIs. Otherwise keys are created that cannot be used in dialog applications. This is because with dialog applications external keys are always converted implicitly in upper case letters.

Locking We recommend that you implement Create() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

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Example of a Create() BAPI

Example of a Create() BAPI The BAPI Create() of the business object type InternalOrder (BUS20745) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Example of a Create() BAPI

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Programming Change() BAPIs

Programming Change() BAPIs Use The BAPI Change() changes an existing instance of an SAP business object type, for example, a sales order. The BAPI Change() is an instance method, whereas the BAPI ChangeMultiple() is a class method (instance-independent).

Features Import Parameters The import parameters of the Change() BAPI must contain the key fields of the business object type. If required, you can create also create these parameters: •

A test run parameter for checking the entry for an object instance before actually creating/changing the instance in the database.

•

A change parameter to identify parameter fields containing modified values and parameter fields that have not been modified.

For more information about these parameters see Standardized Parameters [Page 29].

Export Parameters To make the object key available to the calling program, the entire key fields must be returned in the export parameters. To report messages from the method call back to the calling program, you should create the export parameter RETURN. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

Avoiding Incompatibilities with Customizing Settings It could be possible that certain values set by Customizing appear differently in the BAPI interface. These values cannot be overwritten by a Change() BAPI. To avoid incompatibility with Customizing settings, you should implement a Change() BAPI in the following way: •

The BAPI should transfer all the fields and check them against the Customizing settings. If the Customizing settings write-protect a field, the data in this field cannot be overwritten by data in the BAPI interface.

•

For every incidence of incompatibility an error message must be returned in the return parameter to the calling program. For example, “Customizing settings do not allow the field 'MyAsset-AssetName' to be modified ”.

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BAPI Programming Programming Change() BAPIs

•

All the fields that are assigned default values by Customizing and are therefore writeprotected, must be documented.

Locking We recommend that you implement Change() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

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Example of a Change () BAPI

Example of a Change () BAPI The BAPI Change of the business object type PurchaseRequisition (BUS2105) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Example of a Change () BAPI

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Programming Delete() BAPIs

Programming Delete() BAPIs Use The BAPI Delete() deletes an instance of an SAP business object type from the database. Likewise, the BAPI DeleteMultiple() deletes several instances of a business object type. Delete() BAPIs must always delete entire instances, for example, a whole material master. (Whereas the BAPI Cancel() cancels an instance of a business object, that is the instance to be cancelled remains in the database and an additional instance is created that is canceled. For more information see Programming Cancel() BAPIs [Page 113]). A delete() BAPI can delete immediately or at a later time by setting the deletion flag. The type of deletion you use in your BAPI is irrelevant to the caller, so you do not have to include these details in the BAPI interface. The BAPI Undelete() is used to reset a deletion flag that has been set for a specific object. The BAPIs Delete() and Undelete() are instance methods, whereas the BAPIs DeleteMutliple() and UndeleteMutliple() are class methods (instance-independent).

Features The interfaces of the Delete() and Undelete() BAPIs should be identical.

Import Parameters The BAPI's import parameters have to identify the business object instances to be deleted. •

If an instance is to be deleted, you have to create a parameter for each key field in the business object type.

•

If several instances are to be deleted, you must create a table for the key fields of the business object type. You can do this using a range table.

If required, you can create also create these parameters: •

A test run parameter for checking the entry for an object instance before actually deleting the instance from the database.

•

When the BAPI DeleteMultiple() is used, it must be possible to use the selection criteria to select the object instances to be deleted. To do this you can create selection parameters.

For more information about these parameters see Standardized Parameters [Page 29].

Implement the interface of a Delete() BAPI so that it is not possible to delete all the instances simply by parameterizing the interface, for example by specifying default settings.

Export Parameters To report messages from the method call back to the calling program, you should create only the export parameter Return . For more information about this parameter see Return Parameters (Error Handling) [Page 130].

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BAPI Programming Programming Delete() BAPIs

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

Locking We recommend that you implement Delete() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

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Example of a Delete() BAPI

Example of a Delete() BAPI The BAPI Delete() of the business object type EmployeeTrip (BUS2089) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Programming Cancel() BAPIs

Programming Cancel() BAPIs Use The Cancel() BAPI cancels one instance of a business object. Unlike the BAPI Delete() [Page 110], which deletes an object instance from the database, with the BAPI Cancel(): •

The canceled instance of the business object is not deleted

•

An additional instance is created with which the instance of the business object is deleted

The Cancel() BAPI is used to cancel business processes such as goods movements or invoice receipts. The Cancel() BAPI is an instance method.

Features Import Parameters The data of the instance to be created comes from the data of the business object instance to be cancelled. You can also create further parameters to specify information relevant for the actual cancellation process, for example, the name of the user performing the cancellation. If required, you can also create a test run parameter, which can check the details of the object instance before it is actually canceled. For more information about this parameter see Test Run Parameters [Page 135].

Export Parameters To report messages from the method call back to the calling program, you should create the parameter Return. For more information about this parameter see Return Parameters (Error Handling) [Page 130]. You have to put the key of the created instance in another export parameter.

Locking We recommend that you implement Cancel() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

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Example of a Cancel() BAPI

Example of a Cancel() BAPI The BAPI Cancel() of the business object type GoodsMovement (BUS2017) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Programming Replicate()/SaveReplica() BAPIs

Programming Replicate()/SaveReplica() BAPIs Use To replicate an instance of a business object, for example, if you want to exchange data between two distributed systems in the context of Application Link Enabling (ALE), you have to implement certain standardized BAPIs (see also Using BAPIs in Distributed Systems (ALE) [Page 164]. The objective of replicating business object types is to make specific instances of an object type available on one or more additional systems. The replicated instances are usually created under the same object key. The interface of these BAPIs depends on the characteristics and contents of the business object that is to be replicated. For this reason replicate BAPIs must be implemented for each business object. Business objects instances can be replicated in two ways: •

By request ("Pull") System "A" requests replicates from system "B". Then system "B" replicates the requested business object instances on system "A".

•

Using subscription lists ("Push") In this approach system "B" maintains a list of systems requiring replicates. At regular intervals system "B" replicates the business object instances to all the systems in the list.

Both of the above replication methods can be implemented with the BAPIs Replicate(), SaveReplica() and SaveReplicaMultiple(). These BAPIs are both class methods (instanceindependent).

Features Replicate() The BAPI Replicate() is called in the system which contains the originals of the business object instances to be replicated. The BAPI Replicate() is used for: •

Identifying the business object instances to be replicated and to organize the required data

•

Calling the SaveReplica() methods in the receiving system

The BAPI Replicate() can only request the replication of instances of a business object. The actual replication is carried out when the server system calls one of the SaveReplica() BAPIs described below on the client system. You must follow the steps below: 1. Select the data to be replicated. 2. Determine the receiver. This is done in the ALE distribution model using the function module ALE_SYNC_BAPI_GET_RECEIVER. For information on this function module see Distribution Using BAPIs [Ext.] in the ALE Programming Guide. You can also restrict the number of receivers in the parameter Recipients of the Replicate() BAPI. 3. Loop via the receiver and call the relevant SaveReplica() BAPI.

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Programming Replicate()/SaveReplica() BAPIs 4. Enter a value in the return parameter and complete the Replicate() BAPI.

Import Parameters The interface of the Replicate() BAPI must contain the following parameters: •

Parameters which identify the business object instances to be replicated. You could implement these, for example, using a range table for the key fields of the business object types or using selection parameters that enable you to select instances to be replicated. (See also Selection Parameters [Page 134]).

•

Parameter Recipients This parameter identifies the logical systems in which the business object instances are to be replicated. This parameter is based on the data element BAPILOGSYS. If this parameter is set to “initial”, the receiver is determined using the ALE distribution model.

The interface of the Replicate() BAPI may also contain the following import parameters: •

Parameter RequestChanges This parameter enables modifications of object instances already replicated to be copied directly from engineering change management and forwarded to the receiving system. You should only use this parameter if the business object type in question provides engineering change management. Structure this parameter on the data element . This can have the following values: −

' ' (no value) No value is the standard setting and means that engineering change management will not be accessed.

−

'X' This value means that the modified data is replicated directly from engineering change management.

This parameter must not be used together with the Recipients parameter, because the change pointers in change management are reset, if change management is accessed by the receiver. Other receivers may then not be allowed access. Documentation on this parameter must refer explicitly to this connectivity. •

Other BAPI-specific import parameters, for example, to specify the data range of the instances to be replicated (for example, material with or without plant data).

Export Parameters The BAPI Replicate() should contain the following export parameters: •

The Return parameter in which messages from the method call are returned to the calling program. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

•

A table with information on the object instances to be replicated.

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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BAPI Programming Programming Replicate()/SaveReplica() BAPIs

Locking We recommend that you implement Replicate() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

SaveReplica() and SaveReplicaMultiple() The class method SaveReplica() and the method SaveReplicaMultiple() generate replicates of business object instances. They are used to replicate objects in different systems that are semantically identical. For technical reasons these objects may be created with different objects keys (object IDs). The BAPI SaveReplica() is used by a system to replicate one business object instance on a target system or to modify one business object that has already been replicated. Whilst the SaveReplicaMultiple() BAPI can replicate several business object instances on the target system or modify several instances that have already been replicated. For each business object type to be replicated you have to implement one or both of these methods, according to your requirements. If instances that have already been replicated are to be changed when a SaveReplica() or SaveReplicaMultiple() BAPI is called, the fields that are to be changed (that is, receive new values) and the fields that are to remain the same must be identified. You can do this by flagging the fields, as described in Change Parameters [Page 125].

Import Parameters For the BAPI, all the data required for replicating an individual business object instance must be provided in the import parameters. For the SaveReplicaMultiple() BAPI, all the relevant data for replicating several instances must be provided in the import parameters. All the object keys may be provided, they must, however be able to be derived. If only parts of objects are to be replicated rather than whole objects, you can use other optional import parameters.

Export Parameters To return messages from the method call to the calling program, you should only create the parameter Return for these BAPIs. For more information about this parameter see Return Parameters (Error Handling) [Page 130].

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

Locking We recommend that you implement SaveReplica() BAPIs without the locking function and create your own BAPIs instead that lock the relevant data.

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Example of a SaveReplica() BAPI

Example of a SaveReplica() BAPI The BAPI SaveReplica() of the business object type InternalOrder (BUS2075) is used here as an example. The graphic below shows this BAPI in the BAPI Browser.

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BAPI Programming Example of a SaveReplica() BAPI

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Programming Methods for Sub-Objects

Programming Methods for Sub-Objects Use If a business object type consists of sub-objects, you can implement the following standardized BAPIs to add or remove sub-objects: •

Add This method adds a sub-object to an object type.

•

Remove This method removes a sub-object from an object.

For example, to add or remove the sub-object purchase order item to the business object type purchase order, the BAPIs AddItem() and RemoveItem() could be implemented for the object type, purchase order. The BAPIs Add and Remove are instance methods.

Features Import Parameters Both BAPIs’ import parameters must contain in the function module the data that uniquely identifies the sub-object as well as the key fields of the business object. If required, you can create also create these parameters: •

A test run parameter for checking the entry for an object instance before actually creating the instance in the database.

•

A change parameter to identify parameter fields containing modified values and parameter fields that have not been modified.

For more information about these parameters see Standardized Parameters [Page 29].

Export Parameters You should only create the export parameter RETURN in the BAPI Remove to return messages from the method call to the calling program. For more information about this parameter see Return Parameters (Error Handling) [Page 130]. To make the object key available to the calling program, the key fields of the object type must also be returned in the export parameters of the BAPI Add as well as in the export parameter Return.

Extension parameters You can create extension parameters to enable customers to enhance the functionality of BAPIs without making modifications. For information about extension parameters see Customer Enhancement Concept for BAPIs [Page 65].

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BAPI Programming Programming Methods for Sub-Objects

Locking We recommend that you implement methods of sub-objects without the locking function and create your own BAPIs instead that lock the relevant data.

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Programming Standardized Parameters

Programming Standardized Parameters Purpose There are some parameters that can be created for various BAPIs because they contain the same or equivalent data in all BAPIs. Such parameters are known as “standardized” parameters. They should be implemented the same in all BAPIs.

Process Flow If your BAPI is a standardized BAPI, you should implement it following the programming guidelines described in the following sections.

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BAPI Programming Address Parameters

Address Parameters Use Specific reference structures are defined for address parameters in BAPIs. You should copy these structures to use in your BAPI, especially if the underlying object type uses the central address management (CAM). Use one of the following structures as a copy reference for addresses in BAPIs:

Reference Structure

Use

BAPIADDR1 BAPIADDR2 BAPIADDR3 BAPIADDR1X

Addresses of companies and organizations Addresses of individuals Addresses of contact persons within an organization Change reference structures for addresses of companies and organizations Change reference structures for addresses of individuals Change reference structures for contact persons within an organization

BAPIADDR2X BAPIADDR1X

Keep in mind the following points when you use these reference structures: •

All the fields of the reference structures refer to the central address management (CAM). Only use fields that can also be processed in your application context. If the CAM is already included, then all the fields are relevant.

•

Contrary to the standard guidelines (compare with Internal and External Data Formats [Page 69]), for some coded name parts the text formats (for example, CHAR 20 or CHAR 39) are included as fields in these structures, rather than the internal database keys. These fields are:

−

Address text (fields TITLE_P, TITLE and FORMOFADDRESS)

−

Academic title (fields TITLE_ACA1 and TITLE_ACA2)

−

Name prefixes, for example "von", "van der" (fields PREFIX1 and PREFIX2)

−

Names affixes, for example, titles (field TITLE_SPPL) You cannot expect in these cases that a calling program converts the internal database keys into the external readable form and vice versa. In these cases you can use the function modules below which enter values in these structures or accept changes made to the structures and then assign the correct keys internally.

Function Module

Description

ADDR_CONVERT_FROM_BAPIADDR1

Converts the fields in the structure from the external format into the internal format. Converts the fields in the structure from the internal format into the external format. Converts the fields in the structure from the external format into the internal format.

ADDR_CONVERT_TO_BAPIADDR1 ADDR_CONVERT_FROM_BAPIADDR2

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Address Parameters ADDR_CONVERT_TO_BAPIADDR2 ADDR_CONVERT_FROM_BAPIADDR3 ADDR_CONVERT_TO_BAPIADDR3

•

Converts the fields in the structure from the internal format into the external format. Converts the fields in the structure from the external format into the internal format. Converts the fields in the structure from the internal format into the external format.

If fields are lengthened in the CAM, the associated field in the BAPI reference structure remains the same type and length. A new data element is assigned to this field that can be identified as obsolete in the description and/or short text. The obsolete field is still taken into account in the conversion modules described above. For the new field length a new field with a new name is added to the end of the structure. Currently this affects the following fields:

Existing Field

Length

New Field

Length

In Structure

FORMOFADDR BUILDING

Char 20 Char 10

TITLE BUILD_LONG

Char 30 Char 20

STREET

Char 40

STREET_LNG

Char 60

BAPIADDR1 BAPIADDR1, BAPIADDR2, BAPIADDR3 BAPIADDR1

Preferably, you should use the new, longer fields. •

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When using the reference structure BAPIADDR3, remember that read-only access is possible to all the fields in the company’s address (check table ADRC). If you want to make changes to these fields you have to access the reference structure BAPIADDR1.

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BAPI Programming Change Parameters

Change Parameters Use In BAPIs that cause database changes (for example, Change() and Create() BAPIs), you must be able to distinguish between parameter fields that are to be modified (change-relevant fields) and parameter fields that are to remain unmodified. Using an initial value is no solution because an initial value could also represent a valid new value. Also, in the ABAP programming language as well as on other development platforms, the value “NULL” should not be assigned to a data type to indicate an empty field. Standardized change parameters are used to identify fields with modified values in Change() and Create() BAPIs. You can do this in two ways: •

Flagging Fields to Identify Fields Containing Modified Values

•

Comparing Fields to Identify Fields Containing Modified Values

Flagging Fields to Identify Fields Containing Modified Values In this approach parameter fields containing modified values are identified by including a flag in an additional "change parameter". •

An additional change parameter must be created with the same number of fields and the same field names for every parameter in the BAPI containing modified field values.

•

When the BAPI is called, the fields in the additional change parameter whose counterparts in the corresponding parameter contain modifications, must be marked with an update flag.

This way the BAPI can identify both modified and unmodified fields in the parameter. Follow the conventions below when you create change parameters to identify modified fields: •

The name of the additional change parameter consists of the parameter name with the suffix "X". For instance, if the parameter is called EquiSales, the name of the additional change parameter is EquiSalesX.

•

The additional change parameter must contain exactly the same number of fields and the same field names as the parameter. You must use the data element BAPIUPDATE (CHAR 1) as the data element for the update fields. This can have the following values: •

'X' This value means that the corresponding parameter field contains a modified value.

•

' ' (no value) This means that the corresponding parameter field does not have to be updated.

•

If the parameter is a table, the additional change parameter must also be a table.

A Change() BAPI is used to change the value of the existing distribution channel (Distr_Chan) to Distr_Chan="US". The fields that have been changed should be identified by flagging them. The program objects in the R/3 System affected by this change are:

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Change Parameters Program Object

Name

SAP business object type

PieceOfEquipment

BAPI

Change

Parameter

EquiSales

Fields in parameter EquiSales

SalesOrg=0001' Distr_Chan='US' Division=' Marketing'

Change parameter that identifies modified fields Fields in parameter EquiSalesX

EquiSalesX SalesOrg=' ' Distr_Chan='X' Division=' '

In the parameter EquiSalesX the value in the field Distr_Chan is 'X'. This indicates that the field Distr_Chan of the parameter EquiSales contains a modified value (US). The Change() BAPI then overwrites the existing value in the field Distr_Chan with the current value in the field Distr_Chan in the parameter EquiSales.

Comparing Fields to Identify Fields Containing Modified Values In this approach fields containing modified values are identified by comparing two parameters, one containing the current valid data and the other the new, modified data. When the Change() BAPI is called, the current data in the database and the new, modified data must be entered in the corresponding parameters. The current data set can be transferred, for instance, from a GetDetail() BAPI that has been called. The following comparisons can be made: •

The current data can first be checked against the database contents to ascertain whether it has changed in the meantime. This way any database changes made between the time the data was read by the GetDetail() BAPI and the time the database is updated can be identified.

•

The data in both the parameters can be compared field by field. If the data in two corresponding fields is different, the relevant values must be transferred from the parameter with the new data.

Note the following when you are comparing fields containing modified data. •

A calling program must be able to provide data in all the parameter fields of the Change() BAPI. For this reason, the parameter fields of the Change() BAPI must be exactly the same as the fields in the GetDetail() BAPI of the same business object type.

•

The names of the parameters to be compared must be the same, but the parameter containing the modified data must also have the suffix ‘New’.

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BAPI Programming Change Parameters

For example, if the parameter with the current valid data is called EquiSales, the parameter with the modified data is called EquiSalesNew. •

Both parameters must have exactly the same fields and the same structure.

A Change() BAPI is used to change the value of the existing distribution channel Distr_Chan="US" to Distr_Chan=“EN”. The fields containing modified should be identified by comparing them. The program objects in the R/3 System affected by this change are:

Program Object

Name

SAP business object type

PieceOfEquipment

BAPI

Change

Parameter

EquiSales SalesOrg=' 0001'

Fields in parameter EquiSales

Distr_Chan='US' Division=' Marketing' Parameter for the new data

EquiSalesNew SalesOrg=' 0001'

Fields in parameter EquiSalesNew

Distr_Chan='EN' Division=' Marketing' The fields are compared by: 1. Entering data from the relevant GetDetail() BAPI in the parameter EquiSales. 2. Initializing the parameter EquiSalesNew with the values from the parameter EquiSales. 3. Modifying the required parameter values in the parameter EquiSalesNew, for example: EquiSalesNew-Distr_Chan='EN'.

Which is the Best Way? The table below compares the two ways of identifying fields containing modified values in BAPIs, as described above, and should help you decide which way suits your requirements best.

Area

Comments

Performance

Flagging fields: The flag table can be compressed. Data does not have to be compared. If using in a distributed environment (ALE) the amount of data to be transported by flagging fields is not significantly greater.

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Change Parameters Programming

Flagging fields: BAPI programming is simpler.

Check facilities

Comparing fields: Can check against current database to identify and prevent inconsistencies.

Comprehension

Flagging fields: Fields containing modifications can be flagged, meaning less demands are placed on the caller.

Comparison with related data

Comparing fields: Need to compare with the associated GetDetail() method of the business object type, because all the fields in the Change BAPI() must filled by the calling program.

Application

Flagging fields: Better for performance critical applications. Comparing fields: Better for dialog-orientated applications with critical data.

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BAPI Programming Extension Parameters

Extension Parameters Use The parameters ExtensionIn and ExtensionOut enable customers to enhance BAPI interfaces without modifications and to process customer-specific data automatically. For details see Customer Enhancement Concept for BAPIs [Page 65].

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Return Parameters (Error Handling)

Return Parameters (Error Handling) Use A BAPI should be able to record and classify all possible errors that may occur. You have to create a parameter named Return for every BAPI. This parameter returns exception messages or success messages to the calling program. BAPIs themselves must not trigger any messages (such as MESSAGE xnnn) in the coding. In particular they must not generate terminations or display dialog boxes. Instead, all messages must be intercepted internally and reported back to the calling program in the Return parameter. Otherwise the BAPI will not be processed correctly and control may not be given back to the calling program. All error messages or indeed any message that may be returned by the BAPI, must be defined in message table (Tools → ABAP Workbench →=Development →=Programming environment →=Messages) and described in the documentation for the return parameter. This also applies to the most important or most likely error messages generated by other programs that can be indirectly passed via the BAPI to the application program.

As of Release 4.0 you must not use exceptions in BAPI interfaces. When a termination message (message type A) is triggered, a database rollback is executed in the standard programming model, that is, all tasks performed since the last COMMIT WORK are canceled. When you program BAPIs, we recommend that you also execute a database rollback in the return parameter for termination messages. You must describe this process in the documentation for the Return parameter. For messages of type E (error), the calling program performs the error handling. Application developers are provided with two service BAPIs to diagnose and process error messages from BAPI calls: •

BapiService.MessageGetDetail() which displays the short and long texts of BAPI error messages.

•

BapiService.ApplicationLogGetDetail(), with which information in application logs can be displayed.

Features The export parameter Return can be implemented as follows: •

As a structure, whereby it must be defined in the function module as an export parameter, as well as in the method in the BOR.

•

As a table, whereby it must be defined in the function module as a table parameter, as well as in the method in the BOR as an export parameter.

Before filling the Return parameter you should either initialize the structure with CLEAR or the table with REFRESH and CLEAR.

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BAPI Programming Return Parameters (Error Handling)

If the return parameter is not set or is set to an initial value this means that no error has occurred. The Return parameter may be based on the following reference structures: •

BAPIRET2 We recommend that you use this reference structure as of Release 4.5A.

•

BAPIRET1

Both structures must be filled in the logon language.

Reference Structure BAPIRET2 The structure BAPIRET2 is filled via the function module BALW_BAPIRETURN_GET2. It contains the following fields:

Field

Type

Description

TYPE

CHAR 1

S = success message E = error message W = warning message I = information message A = termination message (abort)

ID

CHAR 20

Message ID The structure BAPIRET2 takes into account the name space extension for the message class as of Release 4.0. If you want messages to be compatible with earlier R/3 Releases, use the message classes before Release 4.0.

NUMBER

NUMC 3

Message number

MESSAGE

CHAR 220

Full message text from the message table. All variables (in fields Message_V1 to Message_V4) have been replaced with text.

LOG_NO

CHAR 20

Application log number This is empty if no log used. Note that for type A error messages (abort), an application log is not created, as in this case there is no COMMIT WORK.

LOG_MSG_NO

NUMC 6

Current message number in application log

MESSAGE_V1 MESSAGE_V2 MESSAGE_V3 MESSAGE_V4

CHAR 50

Fields for the variable texts of the message specified in fields ID and NUMBER.

PARAMETER

CHAR 32

Parameter containing the invalid value.

ROW

INT 4

Line number of the data record containing the invalid value

FIELD

CHAR 30

Field containing the invalid value.

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Return Parameters (Error Handling) SYSTEM

CHAR 10

System (logical system) in which the message was generated.

Reference Structure BAPIRET1 This structure is filled via the function module BALW_BAPIRETURN_GET1. It consists of the fields in the BAPIRET2 structure excluding the fields PARAMETER, ROW and FIELD.

Return Parameters in the ALE Distributed Environment After the function module which converts the IDoc into the corresponding BAPI in the receiving system has been called, status records are written for the IDoc in which messages sent in the return parameter are logged (see also Using BAPIs in Distributed Systems (ALE) [Page 164]. If the field type is filled with E (error) or A (abort) in at least one of the transferred return parameter entries, the status 51 (application document has not been posted) is assigned to all the status records of the IDoc and a ROLLBACK WORK is executed. If the field type is filled with E (error) in at least one of the transferred return parameter entries, the status 51 (error, application document has not been posted) is assigned to all the status records of the IDoc and a COMMIT WORK is executed anyway. Otherwise status 53 (application document posted) is written and a COMMIT WORK executed.

Application Log and Application-Specific Error Tables If the information provided in the Return parameter is not sufficient, you can log errors with the application log. The logging should be done by the BAPI itself so that function modules called directly by this BAPI do not have to be modified. The fields LOG_NO and LOG_MSG_NO of the Return parameter return the application log numbers and their messages.

As of Release 4.6A you can already maintain the log number when you create the application log. Several instances of an application object can be maintained at the same time and can be updated together. The update task can be also used for application logs, that is, log entries are and no longer directly written to the database, they are written via the update task. If you plan to use application logs in your BAPI, you must write these using the update task. For further information on application logs see Creating Applications Logs [Ext.] in the document BC - Extended Function Library Applications [Ext.]. If this still does not provide enough information, the calling application can define its own additional error tables. There are no set guidelines for these additional tables. The Return parameter in your BAPI could give details of the messages in the error tables, for example, if there are error messages (type E) in the table. The calling program then has immediate control over the contents of the error table and does not have to first search for error messages. The use of the application log and error tables enable error messages to be returned if they cannot be adequately returned in the return parameter.

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BAPI Programming Return Parameters (Error Handling)

Note that for type A error messages (abort), an application log is not created, as in this case there is no COMMIT WORK.

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Selection Parameters

Selection Parameters Use The parameters in BAPIs used to search for specific instances of a business object type, for example, BAPI GetList(), have to enable the caller of the BAPIs to specify appropriate selection criteria. In your BAPI create the required selection parameters as structures or tables with the following parameters:

Fields for Value Ranges Field Name

Description

Data Element

SIGN

Selection operator that determines whether the range specified is to be included or excluded.

BAPISIGN

OPTION

Relational operator, for example. Relational operator, e.g. CP (contains pattern) or NP (no pattern)

BAPIOPTION

HIGH

Upper limit of value range

application-specific, for example, MATNR.

LOW

Lower limit of value range

application-specific, for example, MATNR.

You can use the function module BALW_RANGES_CHECK to check the values entered in SIGN and OPTION. Note that when you select a list of objects you have to limit the number of objects selected. You can use the parameter MaxRows to do this. For more information see Programming GetList() BAPIs [Page 91].

Application servers might not support ASCII, but use a different character set instead. If this is the case a problem may arise when you select quantities or ranges or when these are sorted. Because of this a BAPI should always select a range between A-Z, a-z and 0-9.

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BAPI Programming TestRun Parameters

TestRun Parameters Use The parameter TestRun is used in write BAPIs, for example, Create() or CreateFromData(), to check the entries for the object instance in the database before actually creating the object instance. The generation of the instance, for example, creating master data, is only simulated and the data is not written to the database. To simulate the creation of the object instance and to supply the relevant return messages, the BAPI should carry out all the necessary checks (excluding technical checks, such as, establishing the connection to the R/3 System), without actually updating the database.

For BAPIs used in an ALE distributed environment, this parameter must be available in the interface. Updating can be switched on or off using the TestRun parameter. The parameter is based on the data element TESTRUN. This can have the following values: •

' ' (no value) No value means that the data will be posted. This is the default setting.

•

'X' This value means that the BAPI is being called only in simulation mode and updating will not take place.

Keep in mind the following as you are programming: •

Do not assign any internal numbers either for the object itself, or for any dependent objects (for example, EAN numbers or Mat.Ledger No. in the material master).

•

Be careful when calling function modules in other applications as these could assign numbers or update the database.

•

Do not inadvertently write change documents.

•

Create a message in the return parameter of the BAPI that informs users whether the BAPI has been implemented in simulation mode.

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Text Transfer Parameters

Text Transfer Parameters Use Text transfer parameters are used to pass information in a BAPI (e.g. documentation on a business object type) from the R/3 System to a calling program.

Features To transfer documentation texts you have to create the standardized parameters below: •

The import parameter TextFormat that identifies the data format of the text to be transferred. Use the type BAPI_TFRMT for this parameter. This requires the following fixed values that must all be provided by the BAPI:

•

SCR for SAPscript

•

ASC for ASCII

•

RTF for rich text format

•

HTM for hypertext markup language (HTML)

•

The table parameter Text that carries the text to be transferred. Use the reference structure BAPITGB for this parameter.

You can see an example of using text transfer parameters in the BAPI BapiService.FieldhelpGetDocu().

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BAPI Programming Tools for Developing BAPIs

Tools for Developing BAPIs Use You can use the following development tools to develop BAPIs in addition to the standard development tools in the ABAP Workbench: •

The BOR/BAPI Wizard to define BAPIs in the Business Object Repository. This program is described in Defining Methods in the BOR Using the BOR/BAPI Wizard [Page 138].

•

A transaction to automatically generate function modules to convert between internal and external data formats. This transaction is described in Converting Between Internal and External Data Formats [Page 140].

•

The report BBAPIFLD used to generate default values for English field names and parameter names. For further information see the section Specifying Development Objects in the ABAP Dictionary [Page 37] in the report documentation.

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Defining Methods in the BOR Using BOR/BAPI Wizard

Defining Methods in the BOR Using BOR/BAPI Wizard Prerequisites If the function module which your BAPI is based on has been fully implemented or modified you can define it as a method of an SAP business object type or SAP interface type in the Business Object Repository (BOR). You use the BOR/BAPI-Wizard to do this.

Procedure First find the relevant SAP business object type in the BOR: 1. Select Tools → Business Framework → BAPI Development →==Business Object Builder. On the initial Business Object Builder screen you can directly access the SAP business object type or interface type if you know the technical name of the object (object type). You have already identified the technical name in Defining a BAPI and Its Interface [Page 24] Otherwise select Business Object Repository. •

To display object types, in the next dialog box indicate whether you want to display all object types or only business object types. Then select Continue.

•

To display SAP interface types, in the next dialog box select Other settings and then Interface. The application hierarchy is displayed. Search for the required business object type or interface type in the application hierarchy and double click it to open it. 2. When the business object type or interface type is displayed, select Change.

Creating BAPIs as Methods of Business Object Types or Interface Types To define your BAPI as a method of a business object type or interface type: 1. Select Utilities → API Methods → Add method. 2. In the next dialog box enter the name of the function module, for example, BAPI_COMPANYCODE_GETDETAIL and select Continue. 3. In the next dialog box specify the following information for the method to be defined: •

Method A default name for the method is provided, based on the name of the function module. You will have to modify the suggested name.

•

Delete the prefix “BAPI” and the business object name, so that only the method name is left. Begin every new word of the method name with a capital letter and do not use underscores. Example: If the name of the function module is BAPI_SALESORDER_GETSTATUS, the suggested method name might be BapiSalesorderGetstatus. You should edit this so that the resulting name is GetStatus.

•

Texts Enter meaningful descriptions for your BAPI.

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BAPI Programming Defining Methods in the BOR Using BOR/BAPI Wizard

•

Radio buttons Dialog, Synchronous, Instance-independent Enter relevant details for your BAPI. Make sure that a BAPI is not dialog orientated. BAPIs are usually implemented synchronously.

4. Select Next Step. A list of parameters and default names is displayed which you need to edit as required. Modify the parameter names as follows: •

Each new word in the parameter name must start with a capital letter, for example, CompanyCodeDetail.

•

Make sure that the parameter names of the method in the BOR are identical to the parameter names in the function module except for the upper/lower case letters.

•

Also specify whether the individual table parameters are used for data import or data export. Table parameters are marked with a tick in the column 'MLine' (multiple lines).

5. Select Next Step. To create the method select Yes in the next dialog box.

Result After the program has been generated and executed, check that all the definitions have been made correctly by the BOR/BAPI Wizard. To do this look at the newly created method of the business object type or interface type.

The BOR/BAPI Wizard is used only to create new BAPIs for the first time. It is not used to make changes to existing BAPIs. If you make changes to the underlying function module after you have created the BAPI in the BOR, for example, if you make compatible interface enhancements or modify short texts, such changes do not automatically take effect in the BOR. You have to make these changes manually in the BOR. For information about creating and modifying business object types refer to the documentation on SAP Business Workflow [Ext.].

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Converting Internal and External Data Formats

Converting Internal and External Data Formats Prerequisites This section describes how you can generate function modules to convert between internal and external data formats. These function modules are used to: •

Map English and German field names onto each other

•

Carry out ISO code conversions

•

Convert currency amounts into the required external or internal format

•

Convert internal and external keys, for use for example by WBS elements (work breakdown structure)

Note that conversions between internal and external data formats should only be carried out in exceptional circumstances. These exceptions are described in Internal and External Data Formats [Page 69]. To generate the function modules, the relevant internal and external data formats must have been created in the ABAP Dictionary.

Procedure To generate the function module follow the steps below: 1. Select Tools → Business Framework → BAPI Development →==Generate module to map fields. 2. In the appropriate input fields enter the names of the external BAPI structure and the internal working structure you are making the conversion between. Specify the required direction for mapping, i.e. is the internal structure to be mapped onto the external structure or vice versa. 3. Select Function module →=Generate. A dialog box is displayed in which you can enter details of the function module to be generated. The input fields for the name of the function module and the short text contain suggested values which you can accept or change. In the field Function group enter the name of the function group to which the generated function module is to be added. If the function module is being used to convert currency amounts, the fixed point arithmetic for the selected function group must be switched on. In addition to the source text for the function module you can have a blank FORM routine added for your own program code if you have to make manual modifications. To do this, select Form to edit. The FORM routine contains the same parameters as the generated function module. 4. Select Continue. A table is displayed containing suggestions for the conversion of each field of the external BAPI structure. The table contains the following columns: •

Status Indicates if the conversion is possible or if data is missing.

•

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Field in external structure

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BAPI Programming Converting Internal and External Data Formats

Contains the field names of the external BAPI structure. •

Conv. type Displays the conversion type.

•

Field in internal structure Displays the fields of the internal structure to which/from which mapping is to be carried out. For further information select F1 help for columns Status and Conv. type.

5. To generate the function module, select Save. The function module is stored in the Function Builder in the function group you specified.

Result In a few cases it may be necessary to manually edit the source code of a function module that has been automatically generated. It is not yet possible to use this transaction to regenerate an existing function module. To regenerate an existing function module you must first manually delete the function module and then generate it afresh. You can incorporate the generated function modules into the source code of your BAPI as required. •

To map the internal work structures to the external BAPI structures before calling the BAPI

•

To map the result to the internal work structure after the BAPI has been called

•

To map the inbound parameters to the internal structures (import parameter structures) when you are implementing the BAPI

•

To map the result from the internal structure to the BAPI (export parameter structures) when you are implementing the BAPI

The section Application Example [Page 142] illustrates how function modules are used.

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Application Example

Application Example The BAPI used in this fictitious example can read the standard price of a material: bapi_material_getprice importing material like mara-matnr exporting material_price like bapi_material_price. The external structure bapi_material_price contains the following fields:

Fields in External BAPI Structure Field currency_iso currency amount

Description ISO currency code Currency code Amount

Data Element isocd waers bapimatprice

Domain isocd waers bapicurr

The application programmer in the R/3 System who intends to use this BAPI uses the internal structure mat_preis in his or her own program. This structure consists of the following fields:

Fields in Internal Working Structure Field Description Data Element Domain matnr Material number matnr matnr waers Currency code waers waers stprs Unit price stprs strps The BAPI structure bapi_material_price contains an ISO currency code and a currency amount. After calling the BAPI, the application programmer must convert these fields into the internal format used in R/3 so that the fields can be processed. Using the function, Generate module to map fields, (see section Converting Between Internal and External Data Formats [Page 140]), the application developer can generate the function module, map2i_bapi_material_price_to_mat_preis, which converts the currency and amount fields. This function module has the following interface: function map2i_bapi_material_price_to_mat_preis importing external structure bapi_material_price changing internal structure mat_preis exceptions error_during_iso_convertion error_converting_currency_amount. The application code could be as follows:

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BAPI Programming Application Example

... data: matnr like mara-matnr, price like mat_preis, bapi_price like bapi_material_preis. ...

* Call BAPI Call function bapi_material_getprice exporting material = matnr changing material_price = bapi_preis.

* Map and convert the result to internal format call function map2i_bapi_material_price_to_mat_preis exporting external = bapi_preis changing internal = preis. *

exceptions

*

error_during_iso_convertion

*

error_during_currency_amount_conversion

preis-matnr = matnr. ...

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SAP Enhancements to Released BAPIs

SAP Enhancements to Released BAPIs Purpose Application developers who are using BAPIs in their application programs must be able to rely on the fact that the BAPI's interface is not going to change. As a result of this, once a BAPI is released, it must fulfill certain requirements regarding the stability of its interface. If you continue developing your BAPI after you have released it, you need to ensure that any syntax changes or changes to the contents or functionality of the BAPI are downward compatible. Downward compatibility means that applications that were programmed with BAPIs from a specific R/3 Release will not be effected in later R/3 Releases if the syntax or the content of this BAPI changes. Examples of syntax changes are changes to parameter names, or changes to the type or length of a domain. The ABAP Dictionary can automatically test whether syntax changes are compatible. However, only the developer can ensure that content changes are downward compatible. Accordingly, when you enhance a BAPI, you can only differentiate between a compatible and an incompatible enhancement, if the downward compatibility of the BAPI can be verified.

Process Flow When you are enhancing a BAPI, you should attempt to make compatible changes in order to limit the impact of your modifications on existing programs which use the BAPI. For example, when adding a new import parameter, consider whether the interface would function without the parameter. If this is the case, you can make the enhancement to the interface compatible by adding an optional parameter. For further details see Compatible Enhancements [Page 146] and Incompatible Enhancements [Page 148].

For SAP internal development, each enhancement to a BAPI must be created in a project in the BAPI Explorer.

Modifications and Version Management in the BOR Changes made to a BAPI only take effect when the changes are defined in the Business Object Repository (BOR), that is, they are saved and generated. Version management of BAPIs is also carried out in the BOR.

Checks in the ABAP Dictionary Changes to the syntax of BAPIs are automatically checked by the ABAP Dictionary, thereby preventing the BAPI data structure being changed by mistake. •

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Incompatible changes to data elements, domains or structures that are being used by a BAPI that has been released, are rejected by the ABAP Dictionary.

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BAPI Programming SAP Enhancements to Released BAPIs

•

Compatible changes or changes to data elements, domains or structures of a BAPI that has not been released are accepted by the ABAP Dictionary.

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Compatible Enhancements

Compatible Enhancements Use Compatible enhancements are interface enhancements that change the BAPI without effecting the downward compatibility of the BAPI. Applications which access the BAPI are not affected by compatible enhancements.

Features Compatible enhancements are: •

New optional parameters A parameter is considered to be optional if it does not have to be included in a BAPI call. A new optional parameter can be added in any place in the interface.

A new parameter is added to the BAPI SalesOrder.GetList() which can be used as an additional selection criteria for selecting sales orders in the R/3 System. •

New optional fields in structures A field is considered to be optional if it can be left out completely in a BAPI call. The fields must be added to the end of a structure because the function module underlying the BAPI is called via RFC.. It does not matter how the fields are arranged in a structure or table because the whole structure is always forwarded. It is not first broken up into fields.

An additional input field for the applicant's educational background is added to the BAPI Applicant.CreateFromData(). The table below lists the compatible changes that can be made to function modules. We cannot guarantee that this list is complete.

Compatible Changes to Function Modules In interface

New optional parameter as a field New optional parameter as a structure New optional parameter as a table Adding new optional field to the structure. Adding new optional field to the table. Compatible changes to field types (in ABAP Dictionary). Converting mandatory fields to optional fields

In program code

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New additional coding, that does not involve changes to the interpretation/processing logic.

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BAPI Programming Compatible Enhancements Changes to the existing code, which do not involve changing the interpretation or processing logic. Using customer exits.

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Incompatible Enhancements

Incompatible Enhancements Purpose Changes to the contents or functionality of a BAPI often result in the introduction of new parameters without which the interface can no longer function. Often, these changes also cause existing parameters to lose their original meaning. Such modifications are considered to be incompatible enhancements, because they no longer enable the BAPI to be downward compatible. Incompatible enhancements are: •

Changes to the field length

•

Changes to the field type

•

Renaming parameters in the function module or in the method

•

Inserting a field within a structure

•

Deleting parameters and fields

•

Adding new mandatory parameters or fields Parameters can be flagged as mandatory parameters in the BOR However, this is not the case with fields. Fields can only be categorized as mandatory at a semantic level and not at a technical level. This is why the documentation for each parameter must specify which fields can be filled.

The table below lists the incompatible changes to function modules. We cannot guarantee that this list is complete.

Incompatible Changes to Function Modules In interface

New mandatory parameter Adding new fields between existing fields in structure. Adding new fields between existing fields in the table. Adding new mandatory field to the structure. Adding new mandatory field to the table. Incompatible changes to field types (in ABAP Dictionary). Converting mandatory fields to optional fields Renaming a parameter

In program code

New additional coding, involving changes to the interpretation/processing logic. Changes to the existing code that involve changing to the interpretation/processing logic. Adding or removing COMMIT WORK commands in the program.

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Process Flow If changes to BAPIs are incompatible, proceed as follows:

Creating an Additional BAPI To ensure that the interface stability of an existing BAPI is not effected, you must not make any incompatible changes to the existing BAPI. Instead, create one or several, if required, additional BAPIs to replace the existing one. The new BAPI must retain the same name as the existing BAPI. A numeric suffix is simply added to it. This suffix changes if further incompatible changes are made.

A number of incompatible changes must be made to the BAPI FixedAsset.Create(). To implement these changes, a new BAPI, FixedAsset.Create1(), is created, in order to maintain the interface integrity of the BAPI FixedAsset.Create(). If further incompatible modifications must be made to the BAPI at a later date, yet another BAPI, FixedAsset.Create2(), must be created.

Supporting and Labeling the Expiring BAPI After the BAPI has been superseded by a new BAPI, you should not remove the replaced BAPI from the Business Object Repository (BOR) . Instead, you first label this BAPI as expired and continue its support in the release in which you have introduced the new BAPI as well as in the next functional release. During this time the original BAPI must remain fully functional and executable. The following tasks are required when a BAPI has expired (become obsolete): •

Select the relevant SAP business object type in the Business Object Builder and open the node Methods. Position the cursor on the BAPI and select Edit → Change status to → Obsolete.

•

In the BOR, document which method(s) are to replace the expiring BAPI.

•

Record the BAPIs set to “obsolete” in a particular Release in the Note 0107644, “Collective Note for Obsolete BAPIs from Release 4.5A”, in the SAPNet - R/3 Frontend.

•

Inform your users about the relevant successor BAPIs in Release Notes.

The graphic below illustrates the expiry phase of a BAPI. In this example the new BAPI is introduced into Release 4.0. The replaced BAPI is supported in Release 4.0 (in the correction release in which the new BAPI was introduced) and in the next functional Release “F1”. The BAPI can then no longer be used in the following functional Release “F2”.

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Incompatible Enhancements

BAPI Expiry Phase

Release BAPI BAPI

Business Object BAPI BAPI

Business Object

3.1

4.0

F1

F2

Supported at least until F2

Supported as of 4.0

Neu

F = functional Release

Deleting the Replaced BAPI If the expiry phase of a BAPI set to obsolete has come to an end, you can remove the BAPI from the BOR. You should delete an obsolete BAPI as near to the beginning of a new release as possible, so that developers have time to adjust to its successor. To delete a BAPI: •

Delete the method from the BOR. To do this display the relevant SAP business object type in the Business Object Builder. Expand the node Methods Place the cursor on the appropriate BAPI and choose Edit → Delete.

•

Delete the function module that implements the BAPI. In the Function Builder enter the name of the function module in the Function module field and choose Function module → Other functions → Delete.

•

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Record the release in which the BAPI was deleted from the BOR in the Note 0107644, “Collective Note for Obsolete BAPIs from Release 4.5A”, in the SAPNet - R/3 Frontend.

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BAPI Programming Customer Modifications and Developments

Customer Modifications and Developments Purpose If required, customers can carry out modifications to existing BAPIs, for example, create new parameters or parameter fields, or develop new BAPIs following this programming guide.

Prerequisites Customers and partners who want to create new development objects required in the context of a modification or own development, should follow the guidelines in the document Changing the SAP Standard [Ext.] as well as “Guidelines for Modifying the SAP Standard in SAPnet. Also, make sure that the relevant development objects are assigned a name from the customer namespace. For further information see Namespaces [Page 161].

Process Flow Modifications to existing BAPIs or the development of customers’ own BAPIs cannot be made for business object types delivered in the standard. Instead, you create a subtype of the business object type which inherits all the characteristics and methods of this object type. The original object type becomes the supertype. Then you can make the modifications/own developments to the derived subtype. In this way the SAP standard delivered to customers is not changed and the modifications/own developments carried out are retained when the release is upgraded. This procedure also enables BAPIs to be modified in steps because further subordinate sub-types of a business object type can be created. For general information about object types and subtype refer to the documentation for SAP Business Workflow [Ext.]. The following sections describe how subtypes are created and the two ways of enhancing the BAPIs available for this subtype. •

Modifications Use this way if you want to enhance the functions of an existing BAPI for a subtype. For more information see Modifying BAPIs [Page 152].

•

Customer developments Use this method to provide functionality for the subtype which is not covered by any of the existing BAPIs of the subtype nor by any of the BAPIs inherited by the subtype. For further information see BAPI Development [Page 159].

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BAPI Modifications

BAPI Modifications Purpose This section describes the steps involved in modifying an existing BAPI, for example, if new parameters or parameter fields are to be added.

Process Flow BAPI modifications cannot be made to business object types delivered in the standard system. Instead, you have to create a subtype of the business object type and for this subtype you have to redefine the BAPI method inherited from the superior business object. Only the redefined BAPI is then available for the subtype; the original inherited BAPI can only be called from the supertype. Follow these steps: 1. Create a subtype of the required business object type, as described in Creating Subtypes [Page 160]. 2. Redefine the BAPI inherited by the subtype, for example, by adding further parameters or modifying the implementation of the BAPI. There are several ways to do this, as illustrated in the example below: Object type OT has two BAPIs m1 and m2, which are implemented by the function modules BAPI_OT_m1 or BAPI_OT_m2: m1

BAPI_OT_m1

m2

BAPI_OT_m2

OT

If enhancements to BAPI m2 are required, you can use the following implementation options:

Creating a New Function Module for the Implementation Here a new function module (BAPI_OTsub_m2) is created to call the function module of the superior BAPI method (of the supertype). The original functionality is retained and can be enhanced for customer needs. The graphic below illustrates the implementation:

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BAPI Programming BAPI Modifications m1

BAPI_OT_m1

m2

BAPI_OT_m2

OT

OTsub

m2

BAPI_OTsub_m2

call function . . .

If you use this method, when releases are upgraded, the system checks which interface enhancements have been carried out on the original BAPI. For example, if the interface of the original BAPI BAPI_OT_m2 is enhanced, the call in BAPI BAPI_OTsub_m2 must also be enhanced, if the enhanced functionality of the original BAPI is to be used. The advantage of using this method is that the original superior BAPI (BAPI_OT_m2), whose stability has been guaranteed, is cleanly encapsulated. Any changes carried out in the future to the original superior BAPI which do not affect the interface or semantics (for example, corrections and optimizations), are automatically copied to the new BAPI without requiring the subtype to be changed in any way. This method is not a good choice, if the encapsulation affects system performance negatively. This could be the case, if in both BAPI_OT_m2 and in BAPI_OTsub_m2, UPDATE operations are to be made in different fields of the same data record that the developer would like to implement in one single update record (that is with one UPDATE).

Compatible Modifications to the Superior Function Module In principle, the BAPI method of a subtype can be implemented by the same function module as the method of the suoertype (BAPI_OT_m2 in this example). This is possible if the modifications of the interface are compatible, for example, if only new optional parameters have been added (see also SAP Enhancements to Existing BAPIs [Page 144]). The graphic below illustrates the implementation: m1

BAPI_OT_m1

m2

BAPI_OT_m2

OT modifiziert

OTsub

m2

With this implementation method, remember that the modifications must be merged with the original BAPIs every time a release is upgraded. As of Release 4.5A you can use The Modification Assistant [Ext.] to do this.

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BAPI Modifications The advantage of using this option is that the original code and enhancement can be easily compared with one another, to achieve, for example, optimal performance of database UPDATE operations. The main disadvantage is that the encapsulation achieved by separating the supertype and subtype for the BAPI definition actually has to be revoked. When changes have been made, you must ensure that the function module continues to behave the same when the original method of the supertype OT is called. This option can cause problems, if several subtypes of an object type exist in the same system, for example, in the same development system or for several industry solutions in one system, even though they have been created independently of each other, for example for different industry solutions.

Creating the Implementing Function Module as a Copy of the Superior Function Module Here a copy of the function module of the superior BAPI method is created (in this example, BAPI_OT_m2). The graphic below illustrates the implementation: m1

BAPI_OT_m1

m2

BAPI_OT_m2

OT

kopiert

OTsub

m2

BAPI_OTsub_m2

modifiziert

You should only use this option, if the enhancement cannot be done by calling the function module of the superior BAPI method.

If global data is defined or form routines are called in the function group associated with a BAPI function module, you may have to also copy these data declarations and form routines to ensure the copy of the BAPI can be executed. Although it is more flexible to modify a copy of the function module, you still have to check, with every release upgrade, whether changes have been made to the implementation of the superior BAPI method. If changes have been made, you have to copy them to the modified copy. As the origin of the copy is not always supported, we recommend that you do not use this option. Once you have made the required modification to the copy of the function module, assign it as a method to the relevant business object type in the Business Object Repository using the BOR/BAPI Wizard. For further information about the BOR/BAPI Wizard see Defining Methods in the BOR Using the BOR/BAPI Wizard [Page 138]. 3. When you have made the modification, you have to redefine the modified BAPI of the subtype in the BOR, as described in Redefining BAPIs [Page 157].

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BAPI Programming BAPI Modifications

4. If redefined BAPIs of a subtype are also to be used when the BAPI is called, you have to define the delegation relationship between the supertype and subtype. This procedure is described in Defining Delegation Relationships [Page 158].

A delegation relationship is only significant for object-oriented BAPI method calls and not if the implementing function module is called directly. For information about delegation see the documentation on SAP Business Workflow [Ext.].

Application Example

The BAPI Material.GetList() for the business object type Material should contain additional parameters. The function module associated with this BAPI is BAPI_MATERIAL_GETLIST. Customers should first create a sub-type YMaterial of the existing object type Material in the BOR. They will also note that method calls of the business object type YMaterial for the original object type Material are to be processed, provided that the associated method is implemented there. This is described as delegation. (For all methods that are not implemented for the sub-type Ymaterial, the method call is executed from the superordinate business object type, Material.) Customers make the necessary changes in the source code of the function module BAPI_MATERIAL_GETLIST, and makes changes to the interface by creating new, optional parameters. Next, customers create the method GetList() for the sub-type YMaterial using the BOR/BAPI Wizard. The method is linked to the function module BAPI_MATERIAL_GETLIST, where the new parameters are included as part of the method definition. If, on the other hand, the interface is enhanced with new, mandatory parameters, a new function module must be created and assigned to the method YMaterial.GetList(). (Customers can also copy the module BAPI_MATERIAL_GETLIST, for example, to Y_BAPI_MATERIAL_GETLIST, and then edit this copy. At runtime the following process takes place:

–

When the BAPI Material.GetList(), the BAPI YMaterial.GetList() is the one actually executed.

–

In the case of all other method calls, the methods of the superordinate business object type, Material are executed, because these are not implemented for the subtype YMaterial.

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Creating Subtypes

Creating Subtypes To create a subtype: 1. Choose Tools →=Business Framework → BAPI Development →=Business Object Builder or enter the transaction code SWO1. 2. In the field Object type enter the name of the subtype you want to create and sleet Create. 3. In the next dialog box, enter the required details:

–

In the field Supertype enter the name of the object type for which you want to create a subtype.

–

In the field Object type enter the name of the subtype you want to create. Enter appropriate values in the remaining fields.

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BAPI Programming Redefining BAPIs

Redefining BAPIs To redefine a BAPI of a subtype: 1. Choose Tools →=Business Framework → BAPI Development →=Business Object Builder or enter the transaction code SWO1. 2. Display the subtype just created in the change mode. 3. Place the cursor on the BAPI you want to modify and choose Process →=Redefine. 4. Double-click on the BAPI and select the register ABAP. 5. In the Name field of the modified function module enter and save your information.

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Defining Delegation Relationships

Defining Delegation Relationships To define the delegation relationship between the supertype and subtype: 1. Choose Tools →=Business Framework → BAPI Development →=Business Object Builder or enter the transaction code SWO1. 2. Choose Settings → Delegate →=System-wide. 3. Switch to the change mode and select New entries. 4. Enter the name of the original object type (supertype) in the field Object type and the name of the subtype in the field Delegation type. Deactivate the check box GUI-specific. 5. Save your entries.

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BAPI Programming BAPI Development

BAPI Development Purpose Using the information in these BAPI Programming guidelines customers and partners can create new methods for business object types. Your own developments are carried out in the subtypes derived from business object types delivered in the standard and not from the business object types themselves. Use this method to provide new functionality for the subtype which is not covered by any of the existing BAPIs of the subtype nor by any of the BAPIs inherited by the subtype.

Process Flow Follow these steps: 1. Create a subtype of the required business object type, as described in Creating Subtypes [Page 160]. 2. Use the guidelines described in this document to create a new BAPI for the subtype and to implement it in its own function module. The new BAPI can only be used for this subtype and not for the object type from which it was derived (supertype). All existing BAPIs derived from the supertype can continue to be used unmodified.

Application Example

Following on from the example in BAPI Modifications [Page 152], an additional method YGetDetail should be created for the sub-type YMaterial of the business object type Material. The function module associated with this BAPI is Y_BAPI_MATERIAL_GETDETAIL. Customers should create the new method YGetDetail of the business object type YMaterial using the BOR/BAPI Wizard. This method is associated with the function module Y_BAPI_MATERIAL_GETDETAIL. At runtime, when the BAPI Material.YGetDetail is called, the BAPI YMaterial.YGetDetail is actually implemented due to the delegation pointer in the business object type Material.

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Creating Subtypes

Creating Subtypes To create a subtype: 1. Choose Tools →=Business Framework → BAPI Development →=Business Object Builder or enter the transaction code SWO1. 2. In the field Object type enter the name of the subtype you want to create and sleet Create. 3. In the next dialog box, enter the required details:

–

In the field Supertype enter the name of the object type for which you want to create a subtype.

–

In the field Object type enter the name of the subtype you want to create. Enter appropriate values in the remaining fields.

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BAPI Programming Namespaces

Namespaces Definition The namespace concept describes how customers and partners have to name their development objects to avoid overlapping when SAP software is upgraded. Customers and partners can create their own development objects, for example, to implement a new BAPI or to modify an existing BAPI. For further information see Customer Modifications and Developments [Page 151]. In R/3 Release 3.1 the namespaces Y* and Z* were provided for customers, and the namespace J_ was reserved for partners. In R/3 Release 4.0 a new namespace concept was introduced which, together with the longer development object names, made it easier to assign names to objects developed by customers and partners. The Business Object Repository (BOR) introduced before R/3 Release 4.0 still uses the old namespace concept. For this reason the limitations of the old namespace concept still apply to the namespaces for BAPI development objects.

Reserved Namespaces/Prefixes for Various Application Groups User

Prefix

Special SAP project

For example, “JPN” for developments in the Japanese area. Industrial Business Units (IBUs) do not have specific namespaces.

Partners/software houses

The following prefixes are used:

Customers

•

J_y" (where "y” is a single digit allocated namespace) for partners/software houses whose namespaces were assigned before Release 4.0.

•

"JJ" (where "" is the registered namespace) for partners/software houses whose namespaces were assigned after Release 4.0, for example, JJABC.

"Y" and "Z", for function modules matching "Y_" and "Z_".

If a customer or partner creates a new object type that is not a sub-type of another object type, the naming convention for this object type applies to all the sub-objects. In principle, therefore, SAP object types cannot overlap with each other, regardless of the names of the methods, attributes and so on. Sub-object types split the namespace for methods, attributes and so on with the superordinate object type. You must follow the naming conventions for the sub-objects too.

Naming Conventions for BAPI Development Objects Development Object

Created in...

Naming Convention

Domain

ABAP Dictionary

Standard in the respective R/3 Release

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Namespaces Data Element

ABAP Dictionary

Standard used in the respective R/3 Release

Structure

ABAP Dictionary ABAP Dictionary ABAP Dictionary Function Builder Function Builder Function Builder BOR

BAPI*

Field in structures Append structure Function group Function Module Function module parameter Object name (name of object type)

Standard used in the respective R/3 Release Standard used in the respective R/3 Release BAPI__ *, except for parameters in customers’ function modules object name Suffixes are only used if there is/could be a name conflict within SAP. •

If object types from standard applications require the same object name, the node of the component hierarchy is added on as a suffix. For example, the business object type, BusinessProcess in Controlling (CO) would be named BusinessProcessCO

•

If there is a name conflict between a standard application and an IBU, the object type in the standard is assigned the object name without the suffix. The object type in the IBU is assigned the IBU code from the component hierarchy as a suffix.

Prefixes are reserved exclusively for partners and customers. For example, if a customer changes the object type BusinessProcessCO, a possible name for it could be YBusinessProcessCO.

162

Object type (technical object name) Attribute name Method

BOR

*

BOR BOR

Method parameters

BOR

* *, except for modifications using delegation, otherwise delegation does not work.

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Using BAPIs in Distributed Systems (ALE)

Using BAPIs in Distributed Systems (ALE) Purpose Since Release 3.0 ALE (Application Link Enabling) technology has enabled data to be exchanged between individual distributed SAP Systems and non-SAP systems. BAPI Development Even if one of the systems fails, or a communications link is interrupted, the remaining systems must be able to continue to function. Loose coupling means that the individual systems for the most part communicate asynchronously, (with a time delay) with each other. For these reasons messaging is used for data communication between the participating systems in ALE distribution scenarios. As of Release 4.0 you can implement an asynchronous BAPI interface by generating an ALE IDoc interface for the BAPI and using it in an appropriate ALE distribution scenario. For further information on ALE technology and using BAPIs in the context of ALE, see ALE Programming Guide [Ext.]. This section provides a general overview of points you should keep in mind when implementing a BAPI to exchange data asynchronously.

Process Flow When you use BAPIs for asynchronous messaging, the application in the sending system calls the generated ALE IDoc interface instead of the BAPI. The ALE IDoc interface performs the following tasks: •

Creates an IDoc from the BAPI data

•

Sends the IDoc to the target system

•

Receives the IDoc in the target system, creates the BAPI data from the IDoc and calls the BAPI

You can use Transaction BDBG to create the additional objects required for the BAPI in this process, that is, the associated IDoc and the required function modules. This transaction is described in detail in the ALE Programming Guide [Ext.].

Prerequisites Before you can implement a BAPI used to transfer data asynchronously in ALE, make sure that a BAPI of this type is actually required for the task in hand. If at least one of the conditions below applies, you should implement your BAPI as an asynchronous interface: •

Consistent database changes in several systems Data must be updated consistently on both the local system and on the remote system.

•

Loose coupling With a synchronous interface the coupling between the client and the server system is too narrow. If the connection is interrupted the client system would not be able to function properly.

•

Performance The interface has a large volume of data or database operations to be carried on the server system will take a long time. In this situation a synchronous interface cannot be used because performance would be too low.

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Additional Guidelines If you are sure you want to implement your BAPI as an asynchronous interface you should keep in mind the following points in addition to the general BAPI programming guidelines: •

The BAPI must not issue a COMMIT WORK command.

•

The BAPI return parameter must use the reference structure BAPIRET2.

•

All BAPI export parameters with the exception of the return parameter are ignored and are not included in the IDoc that is generated.

•

After the function module which converts the IDoc into the corresponding BAPI in the receiving system has been called, status records are written for the IDoc in which messages sent in the Return parameter are logged. If the field type is filled with E (error) or A (abort) in at least one of the transferred return parameter entries, the status 51 (application document has not been posted) is assigned to all the status records of the IDoc after a ROLLBACK WORK has been executed. If the field type is filled with E (error) in at least one of the transferred return parameter entries, the status 51 (error, application document has not been posted) is assigned to all the status records of the IDoc and a COMMIT WORK is executed. Otherwise status 53 (application document posted) is written and a COMMIT WORK executed.

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BAPI Quality Checklist

BAPI Quality Checklist Definition The check list below contains extracts from the BAPI Quality Checklist used internally in SAP to develop BAPIs. You can refer to this check list during the entire development and implementation of a BAPI.

BAPI Quality Checklist This checklist helps you to develop BAPIs in accordance with the programming guidelines and enables you to implement the best quality BAPIs right from the start. You should use this checklist to manage the development of all BAPIs in your integration scenario.

Scenario Person responsible: Developer BAPIs must be developed as part of an integration scenario. This will ensure that they complement each other, and that access to the R/3 functionality is provided in a structured and practical way. Scenario to be implemented [Name of the scenario] -----------------------------------------------------------------------

Quality of Object Modeling Person responsible: Developer [] Existing object model Business object types used in the scenario and person responsible 1. [Name of business object type] [Name of person responsible] 2. [ ] [ ] 3. [ ] [ ]... BOR methods to be implemented 1. [Name of business object type] [BAPI name] 2. [ ] [ ] 3. [ ] [ ]... Name of the function module 1. [Name of function module] 2. [ ] 3. [ ]...

----------------------------------------------------------------------

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Specification Person responsible: Quality assurance/central development department [ ] BAPI concept or specification has been checked by the central development department and by the responsible quality manager. [Name of the contact person in the central development department] [Name of the quality manager] You must mark the checkbox for all the BAPIs in this development request.

---------------------------------------------------------------------Quality of the Method Concept Person responsible: Developer You must mark the checkbox for all the BAPIs in this development request. Fields and Parameters [ ] All field and parameter names must be in English [ ] All the quantity fields must have units of measurement fields [ ] All currency amount fields must have currency indicator fields [ ] All key fields in GetDetail() and GetList() BAPIs must be displayed in a text field. [ ] All BAPI structures begin with the prefix “BAPI” and all foreign keys are defined. Data conversion [ ] Only internal data formats are used, with the following exceptions: (mark these exceptions): [ ] All the date fields must have the format JJJJMMTT [ ] All currency amounts are based on the domain BAPICURR [ ] PSP elements and similar fields use external keys [ ] Additional fields are provided for ISO codes [ ] Currency amounts with decimal places are displayed with decimal points in the interface, For example, 10.12 is displayed as 10.12 and not as 1012. Security issues [ ] All BAPIs contain authorization checks [ ] All F4 possible entries have authorization checks Updates Database changes can only be made through updates. Commit Work BAPIs containing the COMMIT WORK command (exceptions only) [Name of business object type] [BAPI name] [][] [ ] [ ]....

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BAPI Quality Checklist [ ] No COMMIT WORK in asynchronous BAPIs that are sued in the context of ALE/BAPI Integration ----------------------------------------------------------------------

Quality of the BOR Definition Person responsible: Developer [ ] Table parameters are marked in the BOR "Imp. and Exp." only if they have to be imported as well as exported. Otherwise either the indicator Imp or Exp is used. Person responsible: Central development department [ ] Instance-dependency/instance-independency checked [ ] BAPI name(n) OK (agree name with person in development department) [Name of person] A cross in a checkbox applies to all the BAPIs in this development request.

-----------------------------------------------------------------------Quality of Documentation and Functionality Person responsible: QM A cross in a checkbox applies to all the BAPIs in this development request. Documentation [ ] BAPIs and all the associated parameters are fully documented [ ] Documentation on the parameter RETURN contains all the important return codes and messages [ ] The comprehensibility and user friendliness of the documentation has been checked [ ] Documentation describes the use of the COMMIT WORK command (if applicable) [ ] Documentation on the function module has been saved to the active version [ ] Business object type has been documented [ ] BAPI scenario (ALE Business Process) has been documented Tests [ ] Individual tests OK [ ] Integration tests OK [ ] Calling from external programs OK [Name of quality manager responsible]

------------------------------------------------------------------------

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Authorization to Release Person responsible: Quality assurance/central development department [ ] Authorized by member of central development department [Name of person] [ ] Authorized by quality manager [Name of the quality manager] A cross in a checkbox applies to all the BAPIs in this development request.

-----------------------------------------------------------------------If all the fields have been marked are filled, you can release your BAPI(s) and the development request. Thank you for your cooperation.

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