Why is this important?

[ijmitch]

Comment here with reasons that CORS would be important for CICS to support.

[RussTeubner]

HostBridge offers an implementation of server-side javascript (hb.js) that runs on z Systems and under CICS. CICS customers use our software to create web services (i.e., microservices) which orchestrate access to various program/data artifacts under CICS. Our customers use REST and JSON as the primary design pattern for the externalized API. Following IBM's lead (and the industry in general), we want to promote the use of Swagger for designing, documenting and publishing services implemented via hb.js.

The Swagger client, however, unashamedly requires that the system on which the service executes supports CORS. Thus, in order for any CICS customer to fully exploit Swagger (whether they use hb.js or not), we need CICS to support CORS (specifically the http OPTIONS verb).

It follows that a key aspect of business value is this: Support for CORS will allow organizations to more easily use their existing CICS programs and data to offer API-based services to both internal and external service consumers. This will continue to reinforce z Systems and CICS as a high-value resource in the API economy.