# Issue #4: Authentik OIDC integration

## Objective

Implement Authentik OIDC (OpenID Connect) authentication integration for the Mosaic Stack API. This will enable secure user authentication via the Authentik identity provider, supporting multi-tenant workspaces.

## Approach

1. Install BetterAuth library and dependencies
2. Configure BetterAuth with Authentik OIDC provider
3. Create auth module using BetterAuth
4. Add authentication middleware and guards
5. Configure environment variables for Authentik
6. Create user management service integrated with BetterAuth
7. Write comprehensive tests (TDD approach)

## BetterAuth Configuration

- Use BetterAuth's built-in OIDC support for Authentik
- Leverage BetterAuth's session management
- Integrate with Prisma ORM for user storage

## Progress

- [x] Create scratchpad
- [x] Explore existing codebase
- [x] Install BetterAuth dependencies
- [x] Implement BetterAuth configuration
- [x] Create auth guards and decorators
- [x] Add auth service
- [x] Configure environment
- [x] Write tests (26 tests passing)
- [x] Build and verify
- [x] Code review (all critical issues fixed)
- [x] QA testing (identified improvements for future)
- [x] Fix code review issues

## Testing

- Unit tests for auth service and strategy
- Integration tests for OIDC flow
- E2E tests for protected endpoints
- Target: 85% coverage minimum

## Implementation Summary

### Completed

1. **BetterAuth Integration**: Implemented using BetterAuth library for modern, type-safe authentication
2. **Database Schema**: Added Session, Account, and Verification tables for BetterAuth
3. **Auth Module**: Created complete NestJS auth module with service, controller, guards, and decorators
4. **Shared Prisma Client**: Fixed duplicate PrismaClient issue by using shared instance
5. **Type Safety**: Added proper TypeScript types for AuthUser interface
6. **Error Handling**: Sanitized error logging to prevent sensitive data exposure
7. **Test Coverage**: 26 tests passing covering service, controller, and guards
8. **Code Review**: All critical issues from code review have been addressed

### Key Files Created/Modified

- `apps/api/src/auth/auth.config.ts` - BetterAuth configuration
- `apps/api/src/auth/auth.service.ts` - Authentication service
- `apps/api/src/auth/auth.controller.ts` - Auth routes handler
- `apps/api/src/auth/guards/auth.guard.ts` - Session validation guard
- `apps/api/src/auth/decorators/current-user.decorator.ts` - User extraction decorator
- `apps/api/src/auth/types/auth-user.interface.ts` - Type definitions
- `apps/api/prisma/schema.prisma` - Added auth tables
- Multiple test files with comprehensive coverage

### Future Improvements (from QA)

- Add token format validation tests (Priority 10)
- Add database error handling tests (Priority 9)
- Add session data integrity tests (Priority 9)
- Add request mutation verification (Priority 8)
- Create E2E/integration tests for full OAuth flow
- Add CurrentUser decorator tests

## Notes

- Using BetterAuth instead of custom Passport implementation for modern, maintained solution
- BetterAuth handles OIDC, session management, and user provisioning automatically
- Environment variables configured in `.env.example` for Authentik
- All code review findings addressed
- Build and tests passing successfully (26/26 tests)
