Migrate to use swift-openapi-generator

[Kyle-Ye]

Blocking issues:

• Discourse openapi.json generate issue apple/swift-openapi-generator#72
• Support OpenAPI 3.1 apple/swift-openapi-generator#39
• [BUG] Generated openapi file does not full satisfy the spec rswag/rswag#647
• Fix structural problems with the openapi spec discourse/discourse#22256

Work around:
Use https://github.com/Kyle-Ye/swift-openapi-generator/tree/discourse_3.1.0

[Kyle-Ye]

Old branch dependency:

.package(url: "https://github.com/Kyle-Ye/swift-openapi-generator.git", branch: "discourse_3.1.0"),
.package(url: "https://github.com/Kyle-Ye/OpenAPIKit", branch: "discourse_3.1.0"),

-> (Discourse Docs Issue solved) ->

New branch dependency:

.package(url: "https://github.com/Kyle-Ye/swift-openapi-generator.git", branch: "openapi_31x"),

• -> (swift-openapi-generator OpenAPI 3.1 supported) ->

.package(url: "https://github.com/apple/swift-openapi-generator.git", from: "xxx"),

[Kyle-Ye]

Given there are more issued surfaced out and too many todos in the upstream, I just give up to migrate to OpenAPI right now.

eg.

• Support nullable values apple/swift-openapi-generator#82

Maybe I'll give it a second try next year or the time it reached version 1.0.0.

The WIP progress is tracked via https://github.com/Kyle-Ye/DiscourseKit/tree/feature/open-api

[Kyle-Ye]

Update:

Tried swift-openapi-generator 0.2.1 today.

The OpenAPI 3.1 is supported but the nullable support is still not complete. More issue need to be addressed on discourse OpenAPI doc side.

• Fix OpenAPI doc issue discourse/discourse#23619

See progress via https://github.com/Kyle-Ye/DiscourseKit/tree/feature/open-api-0.2.1

[Lancelotbronner]

I've started investigating as well: https://meta.discourse.org/t/contribute-to-the-discourse-api-docs/56693/4