Note: The IDOC domain is deprecated and is not recommended for developing
new message flows. Instead use the MRM domain with a TDS physical
format. See
MRM parser and domain.
A typical ALE IDoc message that has been sent from SAP to the WebSphere MQ link for R3 consists
of an MQMD header, an MQSAPH header, and the ALE IDoc itself. The
IDoc is made up of fixed size structures:
- The first structure is the Control Structure (DC). This is a complex
element 524 bytes long that contains a fixed set of SAP-defined simple
elements.
- One or more Data Structures (DDs). Each DD is a complex element
1063 bytes long that contains a fixed set of SAP-defined simple elements
that occupies 63 bytes, followed by 1000 bytes of user-defined segment
data.
IBM® Integration Bus uses the IDOC parser
to read and write ALE IDocs that belong to the IDOC domain. When reading
a message, the IDOC parser constructs a message tree from a bit stream.
When writing a message, the IDOC parser creates a bit stream from
a message tree.
The IDOC parser processes the SAP-defined elements in the DC, then,
for each DD, the IDOC parser processes the SAP-defined elements, then
calls the MRM parser to process the user-defined segment data, using
its CWF physical format. The IDOC parser is therefore a model-driven
parser, and requires that you create a message set in which to model
the IDoc message, and deploy it to the broker.
If you want the IDOC domain to parse a particular message, you
must:
- Create a new message set with a CWF physical format, or locate
an existing message set.
- Ensure that either the message set has its Default message
domain project set to IDOC, or the IDOC check
box (under Supported message domains) is selected,
to indicate that the message set supports the IDOC domain.
- Create message definition files in the message set to represent
your message. See Building the message model for the IDOC parser for the steps
involved.
- Add the message set to a broker archive (BAR) file which generates
a message dictionary for use by the MRM parser, and deploy the BAR
file to the broker.
- Select Message Domain as IDOC on
the appropriate node in your message flow.
- Additionally, select Message Set and Message
Format on the node. (You do not need to select Message
Type).