Problem description

Since the v2.0.1 update, the oauth2_token_response model has been renamed and updated to o_auth2_token_exchange. Along with that, an issue occurred where the scope field of the token response was expected to be of type int (for some reason) instead of string as it should be, based on RFC 6749 and previous versions of hydra SDK.

Root of the problem

As figured out by @aeneasr and @jonas-jonas in ory/sdk#223, this problem seems to be caused by handler.go#L827. As mentioned earlier, the scope field should be of type string instead of int, as seen in the proposed change of this PR.

Examples of the problem

These examples show how this change affected the generated python and go clients, but the same behaviour can be found in the rest of the clients. I compare the previous version 1.11.0, which worked with no issues, to the latest version 2.0.1, which cannot complete the token exchange flow successfully.

Python Client

Before (oauth2_token_response.py#L88)

return {
    'access_token': (str,),  # noqa: E501
    'expires_in': (int,),  # noqa: E501
    'id_token': (int,),  # noqa: E501
    'refresh_token': (str,),  # noqa: E501
--> 'scope': (str,),  # noqa: E501
    'token_type': (str,),  # noqa: E501
}

After (o_auth2_token_exchange.py#L89)

return {
    'access_token': (str,),  # noqa: E501
    'expires_in': (int,),  # noqa: E501
    'id_token': (int,),  # noqa: E501
    'refresh_token': (str,),  # noqa: E501
--> 'scope': (int,),  # noqa: E501
    'token_type': (str,),  # noqa: E501
}

Go Client

Before (model_oauth2_token_response.go#L23)

type Oauth2TokenResponse struct {
	AccessToken *string `json:"access_token,omitempty"`
	ExpiresIn *int64 `json:"expires_in,omitempty"`
	IdToken *string `json:"id_token,omitempty"`
	RefreshToken *string `json:"refresh_token,omitempty"`
    --> Scope *string `json:"scope,omitempty"`
	TokenType *string `json:"token_type,omitempty"`
}

After (model_o_auth2_token_exchange.go#L29)

type OAuth2TokenResponse struct {
	AccessToken *string `json:"access_token,omitempty"`
	ExpiresIn *int64 `json:"expires_in,omitempty"`
	IdToken *int64 `json:"id_token,omitempty"`
	RefreshToken *string `json:"refresh_token,omitempty"`
    --> Scope *int64 `json:"scope,omitempty"`
	TokenType *string `json:"token_type,omitempty"`
}

Related issue(s)

This PR came out from ory/sdk#220 and ory/sdk#223.

Importance of the solution

In my opinion, the proposed solution is of high importance. Right now, with the current version of the generated clients, the token change flow, which is the core function of this library, is not working. Hopefully, the suggested update is going to solve this type mismatch and bring the token flows back to normal.

Checklist

• I have read the contributing guidelines.
• I have referenced an issue containing the design document if my change
  introduces a new feature.
• I am following the
  contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security vulnerability, I
  confirm that I got the approval (please contact
  security@ory.sh) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.