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.
# Refactor OAuth2 Provider Code into Dedicated Package
This PR refactors the OAuth2 provider functionality by moving it from the main `coderd` package into a dedicated `oauth2provider` package. The change improves code organization and maintainability without changing functionality.
Key changes:
- Created a new `oauth2provider` package to house all OAuth2 provider-related code
- Moved existing OAuth2 provider functionality from `coderd/identityprovider` to the new package
- Refactored handler functions to follow a consistent pattern of returning `http.HandlerFunc` instead of being handlers directly
- Split large files into smaller, more focused files organized by functionality:
- `app_secrets.go` - Manages OAuth2 application secrets
- `apps.go` - Handles OAuth2 application CRUD operations
- `authorize.go` - Implements the authorization flow
- `metadata.go` - Provides OAuth2 metadata endpoints
- `registration.go` - Handles dynamic client registration
- `revoke.go` - Implements token revocation
- `secrets.go` - Manages secret generation and validation
- `tokens.go` - Handles token issuance and validation
This refactoring improves code organization and makes the OAuth2 provider functionality more maintainable while preserving all existing behavior.
Thomas Kosiewski