Add OpenRPC schema generator

[qweeze]

Closes #54

@smagafurov @spumer Please have a look. I'll add some tests if this looks good enough to you

[spumer]

What about more complicated error schema? OpenRPC allow use extra fields except code and message?

Right now fastapi-jsonrpc support custom ErrorModel which allow you extend jsonrpc error results and this custom schema is visible in openapi (Swagger)

[spumer]

Yep, https://spec.open-rpc.org/#error-object allow custom data too

BaseError (item of route.errors list) have a get_data_model() method. You can use it to pass correct schema into openRPC data part

[qweeze]

Thanks, custom errors' schemas are now supported 818c158

[spumer]

LGTM, other minor improvements like cache and route override/customize schema we can do later.

You can start make tests 🔥
Thank you!

[qweeze]

All right, now we have some tests f9cb6cb
Let me know if you'd like to add any other test cases

[spumer]

All right, now we have some tests f9cb6cb Let me know if you'd like to add any other test cases

Is there support for examples in openRPC?

I mean if we have two error with the same code like (6001, ValidationError) but have different data field. It's possible include this into openRPC?

[qweeze]

Is there support for examples in openRPC?

There is, but it's meant to be used only for params and result values. As for errors, the only place to store them is errors array inside method objects, and they're required to be unique. Spec explicitly states that The Errors MUST have unique error codes.

At the same time, error.data field is not typed, so technically it's OK to "merge" such errors without abusing the spec like this:

{
    "error": 6000,
    "message": "ValidationError",
    "data": {
         "anyOf": [
            {"title": "MyError.Data", "type": "object", "properties": {"details": {"title": "Details", "type": "string"}}, "required": ["details"]},
            {"title": "MyError.Data", "type": "string"}
          ]
    }
}

[spumer]

Can you make it? But i think current implementation of openRPC playground does not supported it.

Other things looks good for me

[qweeze]

Can you make it?

I had to move errors' defs into components.errors, this way tools can resolve $refs in error body. Anyway, data schemes of same-coded errors are now joined with anyOf, I added a test for this case here