The message model

A message model is used by IBM® App Connect Enterprise to model a message format. The message models used by IBM App Connect Enterprise are all based on either the World Wide Web Consortium (W3C) XML Schema 1.0 (XSD) or the JSON Schema, a standard from json-schema.org.

XML Schema is an international standard that defines a language for describing the structure of XML documents. It is suited to describing XML messages that flow between business applications, and it is widely used in the business community for this purpose. IBM App Connect Enterprise uses models that are based on XML Schema to describe the structure of XML messages, as well as messages in a number of other message formats.

JSON Schema defines a language for describing the structure of JSON documents. It is suited to describing JSON messages that flow between business applications, and it is widely used in the business community for this purpose. IBM App Connect Enterprise uses models that are based on JSON Schema to describe the structure of JSON messages. Draft 4 and draft 5 of JSON Schema are supported, including the extensions for OpenAPI V2.0 and V3.0.

Data Format Description Language 1.0 (DFDL) is an open standard modeling language from the Open Grid Forum (OGF) that builds upon the features of XML Schema 1.0 in order to model and validate all kinds of general text and binary data. It uses standard XSD model objects to describe the logical structure of data, together with DFDL annotations that describe the physical text or binary representation of data. IBM App Connect Enterprise uses DFDL schema files to describe text and binary data, including industry standard formats.

WebSphere® Adapter Schema is an IBM extension to XML Schema 1.0. It uses standard XSD model objects to express the logical structure of data, together with IBM annotations that are used when exchanging data with EIS systems that use the WebSphere Adapters of the integration node.

Message definition files within message sets also use standard XSD model objects to express the logical structure of data, together with IBM annotations that describe the physical representation.

Tip: A message set is the original container for message models used by IBM App Connect Enterprise. In IBM App Connect Enterprise, message model schema files contained in applications and libraries are the preferred way to model messages for most data formats. Message sets continue to be supported, and are required if you use the MRM or IDOC domains. If you need to model data formats for use in the MRM or IDOC domains, you must first enable message set development in the IBM App Connect Enterprise Toolkit. For more information, see Enabling message set development .

To understand the different ways that you create and populate message model schema files, see Ways to create message models.