Message Type (SAP Library - SAP Exchange Infrastructure (BC-XI))

Message Type

Use

A message type comprises a data type that describes the structure of a message. At the following points of SAP Exchange Infrastructure you can refer to the message to be exchanged at runtime by using the message type:

More than one message interface can use the same message type. For example, an asynchronous outbound message interface and an asynchronous inbound message interface can reference the same message type because the request message does not need to be mapped.
When defining a message mapping you can directly reference message types to map messages from an outbound interface to messages from a receiver interface.

Note

For technical reasons a data type is not sufficient to describe the instance of a message. In XML schema, data types are defined as abstract types that are not yet fixed to an element. You can only describe an instance of a message when you have specified a data type as an element type. Therefore, a message type defines the root element of a message.

A message type does not define the direction of the message exchange, in other words, whether it is a request or a response. In exceptional cases you can use the same message type for both the request and the response message.

Prerequisites

You have already created a data type that you want to reference from your message type. For more information see the section Prerequisites in Introduction to Interface Development.

Features

A message type:

comprises exactly one data type that determines the contents of the message to be tranferred
is identified by a name and a namespace. The name (together with the namespace) of a message type is located in the uppermost tag of the exchanged message: This is an element tag.

Example

You have defined a message type GreetingRes that links to a simple data type of type xsd:string. The namespace of the message type is http://sap.com/xi/myExample. The corresponding payload might look as follows:

<?xml version="1.0" encoding="utf-8" ?>

<ns1:GreetingRes xmlns:ns1="http://sap.com/xi/myExample"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
Hello Mrs. Miller
</ns1:GreetingRes>

You can specify how a message type is used in more detail in Description.

Activities

Create a message type in the design maintenance of the Integration Builder (see: Creating a New Object).

Enter a description for your message type.

Reference a data type, either by entering the corresponding name and namespace of the data type in the frame Data Type, or by using the search help.

Save your changes.

Example

In the example below, two message interfaces each use the same message type for the request message and the response message: