OpenAPI 2.0 or OpenAPI 3.0?
Initially, Frends API development started with support for OpenAPI 2.0 (also known as Swagger), with full support for the OpenAPI 3.0 specification released in version 5.3. The choice between Swagger/OpenAPI 2.0 and OpenAPI 3.0 specification depends on one thing only:
If you're working with a Frends version prior to 5.3, then the only option is OpenAPI 2.0.
From 5.3 onwards, it is recommended to use the newest version of the specification.
Note that if your current Frends environment is of the 5.2.x series and you're planning to update to version 5.3 or later, it is recommended to convert the OpenAPI 2.0 specification to version 3.0. With the version change, OpenAPI specification validation became stricter, and as a result, features or API key security schemes might not function as before (please refer to the release notes).
For the OpenAPI 2.0 reference manual, please refer to this link.
For the OpenAPI 3.0 reference manual, please refer to this link.
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