Web services assistant in CICS TS 3.1 IBM-CICS

The CICS Web services assistant is a set of batch utilities that can help you transform existing CICS applications into Web services and enable CICS applications to use Web services provided by external providers. The assistant supports rapid deployment of CICS applications for use in service providers and service requesters, with minimal programming effort.

When you use the Web Services Assistant for CICS, you do not have to write your own code for parsing inbound messages and for constructing outbound messages; instead, CICS maps data between the body of a SOAP message and the application program’s data structure.

Resource definitions are, for the most part, generated and installed automatically. You do have to define PIPELINE resources, but you can, in many cases, use one of the pipeline configuration files that CICS provides.

The assistant can create a WSDL document from a simple language structure or a language structure from an existing WSDL document, and the assistant supports COBOL, C/C++, and PL/I. It also generates information used to enable automatic run-time conversion of the SOAP messages to containers and COMMAREAs, and vice versa.

However, the assistant cannot deal with every possibility, and there are times when you will need to take a different approach. Following are some examples:

  • You do not want to use SOAP messages.
  • If you prefer to use a non-SOAP protocol for your messages, you can do so. However, your application programs are responsible for parsing inbound messages and constructing outbound messages.
  • You want to use SOAP messages, but do not want CICS to parse them.
  • For an inbound message, the assistant maps the SOAP body to an application data structure. In some applications, you may want to parse the SOAP body yourself.
  • The CICS Web services assistant does not support your application’s data structure.
  • Although the CICS Web services assistant supports the most common data types and structures, there are some that are not supported. For example, OCCURS DEPENDING ON and REDEFINES on data description entries are not supported

In this situation, you should consider one of the following alternatives:

  • Provide a wrapper program that maps your application’s data to a format that the assistant can support.
  • Use WebSphere Developer for System z. See section 4.2, “WebSphere Developer for System z”.

1. Web services assistant utility programs

The CICS Web services assistant provides two utility programs: DFHLS2WS and DFHWS2LS. They are described in detail in this section.

DFHLS2WS

The DFHLS2WS program generates a Web service description and Web service binding file from a language structure. Example shows sample JCL for running DFHLS2WS.

Example: DFHLS2WS JCL sample

Example: DFHLS2WS JCL sample

The main input parameters are as follows:

  • PDSLIB
  • Specifies the name of the partitioned data set that contains the high-level language data structures to be processed.
  • REQMEM
  • Specifies the name of the partitioned data set member that contains the high-level language structure for the Web service request.
  • For a service provider, the Web service request is the input to the application program.
  • For a service requester, the Web service request is the output from the application program.
  • RESPMEM
    • For a service provider, the Web service response is the output from the application program.
    • For a service requester, the Web service response is the input to the application program.
  • Specifies the name of the partitioned data set member that contains the high-level language structure for the Web service response:
  • LANG
    • PGMNAME
    • Specifies the name of the target CICS application program that is being exposed as a Web service.
    • URI
    • In a service provider, this parameter specifies the relative URI that a client will use to access the Web service. CICS uses the value specified when it generates a URIMAP resource from the Web service binding file created by DFHLS2WS. The parameter specifies the path component of the URI to which the URIMAP definition applies.
    • PGMINT
    • For a service provider, specifies how CICS passes data to the target application program (using a COMMAREA or a channel).
    • WSBIND
    • Specifies the HFS name of the Web service binding file.
    • WSDL
    • Specifies the HFS name of the Web service description file.
    • DFHWS2LS
    • DFHWS2LS generates a language structure and Web services binding file from a Web services description. Example shows sample JCL for running DFHWS2LS.

      Example: DFHWS2LS JCL sample

      Example: DFHWS2LS JCL sample

  • Specifies the language of the language structure to be created.


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