Path parameters as function positional arguments

[tsotnikov]

OpenAPI Specification indicates that if parameter location is path the required property is REQUIRED and its value MUST be true

Ref: https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.1.0.md#parameter-object

With this in mind, this PR:

• Tighten the parsing by throwing an error for path parameters with required=false
• Update the templates to pass the path parameters to the function as positional arguments instead of kwargs
  to improve usability

[dbanty]

Thanks for the contribution! Requiring required seems like a good move. Only thing we'll have to work on is how we approach positional arguments since they're inherently more fragile than the kwarg-only approach we've been taking.

[dbanty]

Only problem with this is that the order of endpoint.path_parameters is not guaranteed. If the declaration order swaps around or there's a slight change in implementation (e.g. at some point we decide to alphabetize kwargs) then generated clients will break and potentially do so in a way that consumers don't catch.

If we want to allow positional args, we'll have to guarantee the order for them. For Path params we could use the order in which they appear in the path, which seems the most logical solution to me. It's going to require a bit more up front parsing work though.

[tsotnikov]

Thanks for the review! I will work on sort them in the order they appear in the path.

[tsotnikov]

Done in b9e8057

[dbanty]

Looks great, thanks! Just one suggestion which I think will make the sorting a bit more efficient.

[tsotnikov]

The lint is failing:

openapi_python_client/parser/openapi.py:283: error: Argument "data" to "ParseError" has incompatible type "List[Property]"; expected "Optional[BaseModel]"  [arg-type]

I guess I am forced to pass endpoint instead of endpoint.path_parameters to ParseError.data as the type is incompatible.

[dbanty]

The lint is failing:

openapi_python_client/parser/openapi.py:283: error: Argument "data" to "ParseError" has incompatible type "List[Property]"; expected "Optional[BaseModel]"  [arg-type]

I guess I am forced to pass endpoint instead of endpoint.path_parameters to ParseError.data as the type is incompatible.

That field is intended to take and then display the part of the schema that's wrong. I think we can just omit it and include the path in the error message.

[dbanty]

Sorry for the delay on this @tsotnikov, I've created a branch in-repo and a PR at #464 so I can update this and finish it off. Thanks for all the hard work!