- Previously, AccessTokenValidationService was a module, and all its public
methods accepted a token. It makes sense to convert it to a class which accepts
a token during initialization.
- Also rename the `sufficient_scope?` method to `include_any_scope?`
- Based on feedback from @rymai
- Mainly whitespace changes.
- Require the migration adding the `scope` column to the
`personal_access_tokens` table to have downtime, since API calls will
fail if the new code is in place, but the migration hasn't run.
- Minor refactoring - load `@scopes` in a `before_action`, since we're
doing it in three different places.
- Move the `Oauth2::AccessTokenValidationService` class to
`AccessTokenValidationService`, since it is now being used for
personal access token validation as well.
- Each API endpoint declares the scopes it accepts (if any). Currently,
the top level API module declares the `api` scope, and the `Users` API
module declares the `read_user` scope (for GET requests).
- Move the `find_user_by_private_token` from the API `Helpers` module to
the `APIGuard` module, to avoid littering `Helpers` with more
auth-related methods to support `find_user_by_private_token`
