z/OS Connect EE: provide for outbound API calls from z, enabling z programs to be consumers of APIs, with simplicity

z/OS Connect EE: provide for outbound API calls from z, enabling z programs to be consumers of APIs, with simplicity.

z/OS Connect EE is extraordinary product that allows mainframe programs and assets to be accessed and consumed as APIs.

With the ubiquity of services accessible with APIs, there is a present need in our organization for mainframe programs, especially CICS programs, to consume APIs in easy and transparent way.

z/OS Connect is the perfect solution. Just reverse the process.


A possible solution:

1. Use the Swagger description of an API as input.

2. a. Write an utility (similar to baqjs2ls) to create an "outbound service", transformation bind files, and request/response copybooks for a high-level language (i.e. Cobol), based on the Swagger input , including CRUD method, URI, parms, query parms, headers…

or
b. Import the Swagger to the API editor and enable it to produce an "outbound service", transformation bind files, and request/response copybooks.

3. Enable the API editor to further modify the request/response for flexibility, as needed (mapping, URL/URI, method, etc). Create an “outbound API” equivalent to the current APIs (where the additional mapping and tweaks are defined).

Then... i.e. in CICS:

4. Create "outbound" WOLA programs for requests flowing from CICS to Liberty/zCEE, accessible by EXEC CICS LINK with commarea or container/channel.

5. CICS application programmers use the request/response copybooks in their code, for API consumption.

6. To consume the API:
a. The CICS application program simply executes a LINK to the "outbound" WOLA program, passing a commarea defined by the request copybook.
b. WOLA passes the request to z/OS Connect, and z/OS Connect:
- uses the “outbound” service to transform the commarea to API and JSON,
- uses the “outbound API” to further modify the request,
- sends a REST API to the API provider
- receives the response from the API provider
- uses the “outbound API” to modify the response,
- uses the “outbound” service to transform the JSON response to commarea
- returns the response through WOLA

c. The CICS application program receives the response in a commarea defined by the response copybook.