Implement dual OAuth flows for Progressive Consent architecture:
Flow 1 (Client Authentication):
- Client authenticates directly to IdP with its own client_id
- Server validates client_id against ALLOWED_MCP_CLIENTS whitelist
- Issues tokens with aud: "mcp-server" for MCP authentication only
- Progressive mode detected via ENABLE_PROGRESSIVE_CONSENT env var
Flow 2 (Resource Provisioning):
- New endpoints: /oauth/authorize-nextcloud, /oauth/callback-nextcloud
- MCP server acts as OAuth client for delegated Nextcloud access
- Stores master refresh tokens with flow_type and audience metadata
- Returns success HTML page after provisioning completion
Scope Authorization Updates:
- Added ProvisioningRequiredError for missing Flow 2 provisioning
- Decorator checks if Nextcloud scopes require provisioning in Progressive mode
- Validates token has Nextcloud scopes before allowing access
Storage Schema Enhancements:
- Added flow_type, is_provisioning, requested_scopes to oauth_sessions
- Enhanced store_oauth_session to support Progressive Consent metadata
- Maintains backward compatibility with hybrid flow
This completes the Progressive Consent implementation, enabling:
- Explicit user consent for resource access
- Stateless server by default (no automatic provisioning)
- Clear separation between authentication and resource access
- Defense in depth with audience-specific tokens
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
Chris Coutinho