XML response processing for passthrough

At run time, XML response processing is initiated when the Link3270 server adapter passes the reply data from the CICS® target application to the CICS Service Flow Runtime DPL Stub program.

If the target application used BMS, the reply is presented in the form of an application data structure (ADS), another name for the symbolic map that is generated by the BMS macros used to define the mapping of the 3270 terminal screen.
Note: The Link3270 server adapter interfaces with the Link3270 bridge mechanism (DFHL3270), which sends vectors to, and receives vectors from, any CICS target application that uses BMS SEND MAP and RECEIVE MAP commands (with some restrictions ) where a single SEND MAP and RECEIVE MAP Application Data Structure (ADS).

The CICS Service Flow Runtime passthrough stub program (DFHMADPP) constructs a reply that is consistent with the format of the request message. When the request message is an XML document (i.e. the header in XML format), then the reply is a complete XML document. When only the application data is XML, then the reply is constructed with a standard format header and the application data as an XML document.

Processing is as follows:
  1. The Link3270 server adapter passes the response data to the CICS Service Flow Runtime Passthrough Stub program (DFHMADPP).

    Since flow composition allows multiple Output Terminals, the response could be one of several different messages.

  2. The CICS Service Flow Runtime Passthrough Stub program (DFHMADPP) constructs a response by performing the following steps:
    1. Calls the CICS Service Flow Runtime COBOL to XML Converter (DFHMAXMO) program. The CICS Service Flow Runtime COBOL to XML Converter (DFHMAXMO) program performs the following steps:
      1. Converts the structure of the header in the response message from a flat (COBOL) format to an XML format.
      2. Places the proper XML tags around the application data that resides in the response message:
        The XML declaration was saved by CICS Service Flow Runtime XML Header Converter program (DFHMAXMI) on the inbound request. That declaration was saved by the CICS Service Flow Runtime DPL stub program.
        <dfhmaad>
        Application data from response message
        </dfhmaad>
      3. Takes the reply data formatted by the user defined Application Data COBOL to XML Converter program and converts it to XML.
    2. Calls the CICS Service Flow Runtime Passthrough XML Converter program (DFHMAXPI).

      The call interface CICS Service Flow Runtime Passthrough XML Converter program (DFHMAXPI) is identical to that of the Application Data XML to COBOL converter program. See Figure 1.

      DFHMAXPI builds the outbound XML passthrough application response message using the application reply data passed to it from the calling system program.

      DFHMAXPI performs the following processes:
      1. Converts the structure of the header in the response message from flat (COBOL) format to an XML format and converts the ADS structure data to XML.
        Note: The CICS Service Flow Runtime XML Conversion programs (DFHMAXI and DFHMAXO) will report any errors that they encounter to the CICS system log, under the CEEMSG section. Additionally, CICS error information will be returned to the service requestor.
Figure 1. XML Response processing - passthrough
Diagram shows the processing that is performed by the Passthrough Stup program to support an XML reply to the service requestor.