Support more than one schema

[cappelaere]

Is your feature request related to a problem? Please describe.
Some of our applications may support different encodings for the same API (example: JSON schema, CBOR, Avro...). Currently, only one schema is supported in the yml file.

Can't it be tackled using specification extensions?
We need the capability to define multiple schemas in yml file

Describe the solution you'd like
Need to support different "Named" schemas in the yml file
Need to have relative references to selected schema

Describe alternatives you've considered
Use different files for different encodings but this makes it more difficult to maintain.

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity 😴
It will be closed in 30 days if no further activity occurs. To unstale this issue, add a comment with detailed explanation.
Thank you for your contributions ❤️

[fmvilas]

Hey Pat! Thanks for your patience. Do you have an example of what you're suggesting here? A bit of context would be great too.

[iridian-ks]

I can't speak to what the original requestor intended. But I do have what seems to be the same issue. Our scenario is we have a Kafka topic that has multiple schemas and we need documentation for every schema in the topic for our developers to know all of the different messages they'll need to handle.

Right now, it looks like we have this in the spec:

...
"subscribe": {
    "message": {
          "payload": {} #<--- schema defined here
     }
}
...

I think what we want is something like this:

"subscribe": {
    "message": {
        "payloads": [
             {
                   # first schema
             },
             {
                   # second schema
             }
        ]
    }
}

[magicmatatjahu]

@iridian-ks HI! payload field must contain the Schema Object. By default it's a AsyncAPI Schema (which is superset of the JSON Schema in the draft-07), so you can use the oneOf combined keyword for the payload field, like:

subscribe:
  message:
    payload: 
      oneOf:
        - ...first schema
        - ...second schema
        - ...n schema

and you don't need, the payloads.

Btw. issue is related to define schemas in the different format, so it's not suit for your case, this issue is related - #528

[derberg]

Our scenario is we have a Kafka topic that has multiple schemas and we need documentation for every schema in the topic for our developers to know all of the different messages they'll need to handle.

@magicmatatjahu I think that @iridian-ks is more interested in providing multiple messages definitions with schema than multiple schemas for one message. You can use oneOf under message object

[fmvilas]

@cappelaere would you mind clarifying this issue? Do you mean you need to support multiple schema languages as defined in #622?