Mapping transport headers

Use the Graphical Data Mapping editor to transform transport headers.

About this task

When you create a top level message map, only the Properties folder is initially included in the map, and a default transformation from input to output properties is created in a local map. You can then use the Message Assembly properties page in the Graphical Data Mapping editor to modify the transport headers that you might include in the map.

Depending on how you add a transport header to a message map, the component can be deleted, initialized, or transformed:
  • To pass unchanged a transport header, do not add it to the message map.
  • To read elements from a transport header, add it only to the input message assembly of the message map. The Mapping node passes it through unchanged.
  • To modify elements in a transport header, add it to input message assembly and to the output message assembly, and provide transforms to copy and modify the header. The Mapping node deletes the input transport header, and creates a new output transport header containing the result of your transformations.
  • To add a transport header to your message, add the header to the output message assembly and populate at least one field. The Mapping node creates a new output transport header containing the results of your transformations.
  • To delete a transport header, add it to the output message assembly and do not set any field at all. The Mapping node deletes the transport header from the output message.
  • MQ Headers
    • MQMD
    • MQCFH header with root element MQPCF
    • MQCIH
    • MQDLH
    • MQIIH
    • MQMDE
    • MQRFH
    • MQRFH header with MQRFH2 or MQRFH2C parser
    • MQRMH
    • MQSAPH
    • MQWIH
    • SMQ_BMH
  • Email Headers
    • EmailOutputHeader
  • HTTP Headers
    • HTTPInputHeader
    • HTTPReplyHeader
    • HTTPRequestHeader
    • HTTPResponseHeader
  • JMSTransport

Procedure

Complete the following steps to transform data in a transport header by using a message map:

  1. Decide whether you need a transport header in the input message assembly, the output message assembly, or both. You may want to copy, initialize, or modify elements of a transport header. For more information, see Choosing a mapping action.
    Note: The Mapping node copies the transport headers from input to output, unchanged, when they are not included in the message map.
  2. Add a transport header to the input message assembly, the output message assembly, or both. For more information, see Customizing a message map to include a message assembly component.

    For example, select MQMD to include MQMD headers in the input message assembly of the message map:

    Screen capture that shows the Add or Remove Headers and Folders window, in which you can select the headers you want to include in the map

  3. Optional: Define a Move transform between the input transport header and the output transport header to copy all the input values onto the output values.
    Note: If you need to modify only some fields in a transport header, you can use a Move transform to copy the transport header unchanged, and then use the Override function to modify the elements you must update. For more information, see Applying mapping overrides.

    You can do this in any of the following ways:

    • In the message map, right-click a transport header on the input message assembly, and select Add Connection. Move the mouse to the output local transport header, and click the transport header to define the Move transform.
    • In the message map, right-click a transport header on the input message assembly, and select Quick Link. A new window appears where you can select a transport header as the output element. Use this option when you have a long list of output elements. You can filter the list in Quick link too.
  4. Define transforms between the input transport header and the output transport header. For more information, see Specifying a transform (mapping operation) and Transform types in the Graphical Data Mapping editor.

What to do next

Define additional transformations between other elements in the message map. For more information about the available transforms, see Transform types in the Graphical Data Mapping editor.