Summary

This PR fixes a Pydantic v2.12+ deprecation warning in OidcClientAuthConfig._validate_credentials.

The warning:

DeprecationWarning: Using `@model_validator` with mode='after' on a classmethod is deprecated

Changes

In Pydantic v2.12, using @model_validator(mode="after") with a classmethod-style signature (cls, values) was deprecated in favor of an instance method signature (self).

Before:

@model_validator(mode="after")
def _validate_credentials(cls, values):
    d = values.__dict__ if hasattr(values, "__dict__") else values
    has_user_pass = bool(d.get("username")) and bool(d.get("password"))
    # ...
    return values

After:

@model_validator(mode="after")
def _validate_credentials(self):
    has_user_pass = bool(self.username) and bool(self.password)
    # ...
    return self

Benefits

• Eliminates deprecation warning spam in user logs
• Uses direct attribute access instead of dict gymnastics
• Cleaner, more idiomatic Pydantic v2 code
• No functional changes - same validation logic

Testing

This is a non-breaking change that maintains identical validation behavior. The only difference is the method signature and attribute access pattern.

References

• Pydantic v2 model_validator documentation
• Pydantic changelog noting this deprecation