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:
- 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.
- The CICS Service Flow Runtime Passthrough
Stub program (DFHMADPP) constructs a response by performing the following
steps:
- 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:
- Converts the structure of the header in the response message from a flat
(COBOL) format to an XML format.
- 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>
- Takes the reply data formatted by the user defined Application Data COBOL
to XML Converter program and converts it to XML.
- 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:
- 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