Add comprehensive OAuth2 enum types to codersdk following RFC specifications:
- OAuth2ProviderGrantType (RFC 6749)
- OAuth2ProviderResponseType (RFC 6749)
- OAuth2TokenEndpointAuthMethod (RFC 7591)
- OAuth2PKCECodeChallengeMethod (RFC 7636)
- OAuth2TokenType (RFC 6749, RFC 9449)
- OAuth2RevocationTokenTypeHint (RFC 7009)
- OAuth2ErrorCode (RFC 6749, RFC 7009, RFC 8707)
Add OAuth2TokenRequest, OAuth2TokenResponse, OAuth2TokenRevocationRequest,
and OAuth2Error structs to the SDK. Update OAuth2ClientRegistrationRequest,
OAuth2ClientRegistrationResponse, OAuth2ClientConfiguration, and
OAuth2AuthorizationServerMetadata to use typed enums instead of raw strings.
This makes codersdk the single source of truth for OAuth2 types, eliminating
duplication between SDK and server-side structs.
Closes#21476
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Publish supported OAuth2 scopes from RBAC external scope names
This PR updates the OAuth2 metadata endpoints to publish the supported scopes from the RBAC external scope names. Previously, the `ScopesSupported` field was empty with a TODO to implement a scope system. Now, both the authorization server metadata and protected resource metadata endpoints return the list of scopes from `rbac.ExternalScopeNames()`.
The tests have been updated to verify that the correct scopes are being returned in the metadata responses.
This PR adds a readiness wait to OAuth2 metadata endpoint tests to avoid rare races with server startup. Instead of immediately making HTTP requests, the tests now use `testutil.Eventually` to retry the requests until they succeed, with a short interval between attempts. This helps prevent flaky tests that might fail due to timing issues during server initialization.
Fixes: https://github.com/coder/internal/issues/996
# OAuth2 Provider Code Reorganization
This PR reorganizes the OAuth2 provider code to improve separation of concerns and maintainability. The changes include:
1. Migrating OAuth2 provider app validation tests from `coderd/oauth2_test.go` to `oauth2provider/provider_test.go`
2. Moving OAuth2 client registration validation tests to `oauth2provider/validation_test.go`
3. Adding new comprehensive test files for metadata and validation edge cases
4. Renaming `OAuth2ProviderAppSecret` to `AppSecret` for better naming consistency
5. Simplifying the main integration test in `oauth2_test.go` to focus on core functionality
The PR maintains all existing test coverage while organizing the code more logically, making it easier to understand and maintain the OAuth2 provider implementation. This reorganization will help with future enhancements to the OAuth2 provider functionality.
Ehab Younes