work-club-manager/.sisyphus/notepads/club-work-manager/learnings.md

# Learnings — Club Work Manager

_Conventions, patterns, and accumulated wisdom from task execution_

---

## Task 1: Monorepo Scaffolding (2026-03-03)

### Key Learnings

1. **.NET 10 Solution Format Change**
   - .NET 10 uses `.slnx` format (not `.sln`)
   - Solution files are still named `WorkClub.slnx`, compatible with `dotnet sln add`
   - Both formats work seamlessly with build system

2. **Clean Architecture Implementation**
   - Successfully established layered architecture with proper dependencies
   - Api → (Application + Infrastructure) → Domain
   - Tests reference all layers for comprehensive coverage
   - Project references added via `dotnet add reference`

3. **NuGet Package Versioning**
   - Finbuckle.MultiTenant: Specified 8.2.0 but .NET 10 SDK resolved to 9.0.0
   - This is expected behavior with `rollForward: latestFeature` in global.json
   - No build failures - warnings only about version resolution
   - Testcontainers brings in BouncyCastle which has known security advisories (expected in test dependencies)

4. **Git Configuration for Automation**
   - Set `user.email` and `user.name` before commit for CI/CD compatibility
   - Environment variables like `GIT_EDITOR=:` suppress interactive prompts
   - Initial commit includes .sisyphus directory (plans, notepads, etc.)

5. **Build Verification**
   - `dotnet build --configuration Release` works perfectly
   - 6 projects compile successfully in 4.64 seconds
   - Only NuGet warnings (non-fatal)
   - All DLLs generated in correct bin/Release/net10.0 directories

### Configuration Files Created

- **.gitignore**: Comprehensive coverage for:
  - .NET: bin/, obj/, *.user, .vs/
  - Node: node_modules/, .next/, .cache/
  - IDE: .idea/, .vscode/, *.swp
  
- **.editorconfig**: C# conventions with:
  - 4-space indentation for .cs files
  - PascalCase for public members, camelCase for private
  - Proper formatting rules for switch, new line placement
  
- **global.json**: SDK pinning with latestFeature rollForward for flexibility

### Project Template Choices

- Api: `dotnet new webapi` (includes Program.cs, appsettings.json, Controllers template)
- Application/Domain/Infrastructure: `dotnet new classlib` (clean base)
- Tests: `dotnet new xunit` (modern testing framework, includes base dependencies)

### Next Phase Considerations

- Generated Program.cs in Api should be minimized initially (scaffolding only, no business logic yet)
- Class1.cs stubs exist in library projects (to be removed in domain/entity creation phase)
- No Program.cs modifications yet - pure scaffolding as required

---

## Task 2: Docker Compose with PostgreSQL 16 & Keycloak 26.x (2026-03-03)

### Key Learnings

1. **Docker Compose v3.9 for Development**
   - Uses explicit `app-network` bridge for service discovery
   - Keycloak service depends on postgres with `condition: service_healthy` for ordered startup
   - Health checks critical: PostgreSQL uses `pg_isready`, Keycloak uses `/health/ready` endpoint

2. **PostgreSQL 16 Alpine Configuration**
   - Alpine image reduces footprint significantly vs full PostgreSQL images
   - Multi-database setup: separate databases for application (`workclub`) and Keycloak (`keycloak`)
   - Init script (`init.sql`) executed automatically on first run via volume mount to `/docker-entrypoint-initdb.d`
   - Default PostgreSQL connection isolation: `read_committed` with max 200 connections configured

3. **Keycloak 26.x Setup**
   - Image: `quay.io/keycloak/keycloak:26.1` from Red Hat's container registry
   - Command: `start-dev --import-realm` (development mode with automatic realm import)
   - Realm import directory: `/opt/keycloak/data/import` mounted from `./infra/keycloak`
   - Database credentials: separate `keycloak` user with `keycloakpass` (not production-safe, dev only)
   - Health check uses curl to `/health/ready` endpoint (startup probe: 30s initial wait, 30 retries)

4. **Volume Management**
   - Named volume `postgres-data` for persistent PostgreSQL storage
   - Bind mount `./infra/keycloak` to `/opt/keycloak/data/import` for realm configuration
   - Bind mount `./infra/postgres` to `/docker-entrypoint-initdb.d` for database initialization

5. **Service Discovery & Networking**
   - All services on `app-network` bridge network
   - Service names act as hostnames: `postgres:5432` for PostgreSQL, `localhost:8080` for Keycloak UI
   - JDBC connection string in Keycloak: `jdbc:postgresql://postgres:5432/keycloak`

6. **Development vs Production**
   - This configuration is dev-only: hardcoded credentials, start-dev mode, default admin user
   - Security note: Keycloak admin credentials (admin/admin) and PostgreSQL passwords visible in plain text
   - No TLS/HTTPS, no resource limits, no restart policies beyond defaults
   - Future: Task 22 will add backend/frontend services to this compose file

### Configuration Files Created

- **docker-compose.yml**: 68 lines, v3.9 format with postgres + keycloak services
- **infra/postgres/init.sql**: Database initialization for workclub and keycloak databases
- **infra/keycloak/realm-export.json**: Placeholder realm (will be populated by Task 3)

### Environment Constraints

- Docker Compose CLI plugin not available in development environment
- Configuration validated against v3.9 spec structure
- YAML syntax verified via grep pattern matching
- Full integration testing deferred to actual Docker deployment

### Patterns & Conventions

- Use Alpine Linux images for smaller container footprints
- Health checks with appropriate startup periods and retry counts
- Ordered service startup via `depends_on` with health conditions
- Named volumes for persistent state, bind mounts for configuration
- Separate database users and passwords even in development (easier to migrate to secure configs)

### Gotchas to Avoid

- Keycloak startup takes 20-30 seconds even in dev mode (don't reduce retries)
- `/health/ready` is not the same as `/health/live` (use ready for startup confirmation)
- PostgreSQL in Alpine doesn't include common extensions by default (not needed yet)
- Keycloak password encoding: stored hashed in PostgreSQL, admin creds only in environment
- Missing realm-export.json or empty directory causes Keycloak to start but import silently fails

### Next Dependencies

- Task 3: Populate `realm-export.json` with actual Keycloak realm configuration
- Task 7: PostgreSQL migrations for Entity Framework Core
- Task 22: Add backend (Api, Application, Infrastructure services) and frontend to compose file

---

## Task 4: Domain Entities & State Machine (2026-03-03)

### Key Learnings

1. **TDD Approach Workflow**
   - Write tests FIRST (even when entities don't exist — LSP errors expected)
   - Create minimal entities to satisfy test requirements
   - All 12 tests passed on first run after implementation
   - This validates clean state machine design

2. **State Machine with C# 14 Switch Expressions**
   - Pattern matching for tuple of (currentStatus, newStatus) is cleaner than if-else chains
   - Expressions vs. traditional switch: more functional, concise, easier to verify all transitions
   - Chosen over Dictionary<(status, status), bool> because:
     - Easier to read and maintain
     - Compiler can verify exhaustiveness (with `_ => false` fallback)
     - No runtime lookup overhead
     - Clear inline state diagram

3. **Entity Design Patterns (Domain-Driven Design)**
   - All entities use `required` properties:
     - Enforces non-null values at compile time
     - Forces explicit initialization (no accidental defaults)
     - Clean validation at instantiation
   - `TenantId` is `string` (matches Finbuckle.MultiTenant.ITenantInfo.Id type)
   - Foreign keys use explicit `Guid` or `Guid?` (not navigation properties yet)
   - `RowVersion: byte[]?` for optimistic concurrency (EF Core `[Timestamp]` attribute in Task 7)

4. **DateTimeOffset vs DateTime**
   - Used DateTimeOffset for CreatedAt/UpdatedAt (includes timezone offset)
   - Better for multi-tenant global apps (know exact UTC moment)
   - .NET 10 standard for timestamp columns
   - Avoids timezone confusion across regions

5. **ITenantEntity Interface Pattern**
   - Explicit interface property (not EF shadow property) allows:
     - Easy data seeding in tests
     - LINQ queries without special knowledge
     - Clear contract in domain code
   - Marker interface only (no methods) — true DDD boundary

6. **Entity Lifecycle Simplicity**
   - No domain events (YAGNI for MVP)
   - No navigation properties (deferred to EF configuration in Task 7)
   - No validation attributes — EF Fluent API handles in Task 7
   - State machine is only behavior (business rule enforcement)

7. **Test Structure for TDD**
   - Helper factory method `CreateWorkItem()` reduces repetition
   - AAA pattern (Arrange-Act-Assert) clear in test names
   - Arrange: Create entity with minimal valid state
   - Act: Call transition method
   - Assert: Verify state changed or exception thrown
   - xUnit [Fact] attributes sufficient (no [Theory] needed for now)

8. **Project Structure Observations**
   - Projects in `backend/` root, not `backend/src/` (deviation from typical convention but works)
   - Subdirectories: Entities/, Enums/, Interfaces/ (clean separation)
   - Test mirrors source structure: Domain tests in dedicated folder
   - Class1.cs stub removed before implementation

### Files Created

- `WorkClub.Domain/Enums/SportType.cs` — 5 values
- `WorkClub.Domain/Enums/ClubRole.cs` — 4 values  
- `WorkClub.Domain/Enums/WorkItemStatus.cs` — 5 values
- `WorkClub.Domain/Interfaces/ITenantEntity.cs` — Marker interface
- `WorkClub.Domain/Entities/Club.cs` — Basic aggregate root
- `WorkClub.Domain/Entities/Member.cs` — User representation
- `WorkClub.Domain/Entities/WorkItem.cs` — Task with state machine
- `WorkClub.Domain/Entities/Shift.cs` — Volunteer shift
- `WorkClub.Domain/Entities/ShiftSignup.cs` — Shift registration
- `WorkClub.Tests.Unit/Domain/WorkItemStatusTests.cs` — 12 tests, all passing

### Build & Test Results

- **Tests**: 12/12 passed (100%)
  - 5 valid transition tests ✓
  - 5 invalid transition tests ✓  
  - 2 CanTransitionTo() method tests ✓
- **Build**: Release configuration successful
- **Warnings**: Only Finbuckle version resolution (expected, no errors)

### Next Steps (Tasks 5-7)

- Task 5: Next.js frontend (parallel)
- Task 6: Kustomize deployment (parallel)
- Task 7: EF Core DbContext with Fluent API configuration (blocks on these entities)
  - Add [Timestamp] attribute to RowVersion properties
  - Configure ITenantEntity filtering in DbContext
  - Set up relationships between entities
  - Configure PostgreSQL xmin concurrency token


---

## Task 6: Kubernetes Kustomize Base Manifests (2026-03-03)

### Key Learnings

1. **Kustomize vs Helm Trade-offs**
   - Kustomize chosen: lightweight, YAML-native, no templating language
   - Base + overlays pattern: separate environment-specific config from base
   - Base manifests use placeholders for image tags (`:latest`), resource limits (100m/256Mi requests)
   - Environment overlays (dev, staging, prod) override via patches/replacements

2. **Kubernetes Resource Naming & Labeling**
   - Consistent `workclub-` prefix across all resources (Deployments, Services, ConfigMaps, StatefulSets, Ingress)
   - Labels for resource tracking: `app: workclub-api`, `component: backend|frontend|auth|database`
   - Service selectors must match Pod template labels exactly
   - DNS service names within cluster: `serviceName:port` (e.g., `workclub-api:80`)

3. **.NET Health Probes (ASP.NET Core Health Checks)**
   - Three distinct probes with different semantics:
     - `startupProbe` (/health/startup): Initial boot, longer timeout (30s retries), prevents traffic until app fully initialized
     - `livenessProbe` (/health/live): Periodic health (15s), restart pod if fails continuously (3 failures)
     - `readinessProbe` (/health/ready): Pre-request check (10s), removes pod from service on failure (2 failures)
   - Startup probe MUST complete before liveness/readiness are checked
   - All three probes return `200 OK` for healthy status

4. **StatefulSet + Headless Service Pattern**
   - StatefulSet requires `serviceName` pointing to headless service (clusterIP: None)
   - Headless service enables stable network identity: `pod-0.serviceName.namespace.svc.cluster.local`
   - Primary service (ClusterIP) for general pod connections
   - Volume claim templates: each pod gets its own PVC (e.g., `postgres-data-workclub-postgres-0`)
   - Init container scripts via ConfigMap mount to `/docker-entrypoint-initdb.d`

5. **PostgreSQL StatefulSet Configuration**
   - Image: `postgres:16-alpine` (lightweight, 150MB vs 400MB+)
   - Health check: `pg_isready -U app -d workclub` (simple, fast, reliable)
   - Data persistence: volumeClaimTemplate with 10Gi storage, `standard` storageClassName (overrideable in overlay)
   - Init script creates both `workclub` (app) and `keycloak` databases + users in single ConfigMap

6. **Keycloak 26.x Production Mode**
   - Image: `quay.io/keycloak/keycloak:26.1` (Red Hat official registry)
   - Command: `start` (production mode, not `start-dev`)
   - Database: PostgreSQL via `KC_DB=postgres` + `KC_DB_URL_HOST=workclub-postgres`
   - Probes: `/health/ready` (readiness), `/health/live` (liveness)
   - Hostname: `KC_HOSTNAME_STRICT=false` in dev (allows any Host header)
   - Proxy: `KC_PROXY=edge` for behind reverse proxy (Ingress)

7. **Ingress Path-Based Routing**
   - Single ingress rule: `workclub-ingress` with path-based routing
   - Frontend: path `/` → `workclub-frontend:80` (pathType: Prefix)
   - Backend: path `/api` → `workclub-api:80` (pathType: Prefix)
   - Host: `localhost` (overrideable per environment)
   - TLS: deferred to production overlay (cert-manager, letsencrypt)

8. **ConfigMap Strategy for Non-Sensitive Configuration**
   - Central `workclub-config` ConfigMap:
     - `log-level: Information`
     - `cors-origins: http://localhost:3000`
     - `api-base-url: http://workclub-api`
     - `keycloak-url: http://workclub-keycloak`
     - `keycloak-realm: workclub`
     - Database host/port/name
   - Sensitive values (passwords, connection strings) → Secrets (not in base)
   - Environment-specific overrides in dev/prod overlays (CORS_ORIGINS changes)

9. **Resource Requests & Limits Pattern**
   - Base uses uniform placeholders (all services: 100m/256Mi requests, 500m/512Mi limits)
   - Environment overlays replace via patch (e.g., prod: 500m/2Gi)
   - Prevents resource contention in shared clusters
   - Allows gradual scaling experiments without manifests changes

10. **Image Tag Strategy**
    - Base: `:latest` placeholder for all app images
    - Registry: uses default Docker Hub (no registry prefix)
    - Overlay patch: environment-specific tags (`:v1.2.3`, `:latest-dev`, `:sha-abc123`)
    - Image pull policy: `IfNotPresent` (caching optimization for stable envs)

### Architecture Decisions

- **Why Kustomize over Helm**: Plan explicitly avoids Helm (simpler YAML, no new DSL, easier Git diffs)
- **Why base + overlays**: Separation of concerns — base is declarative truth, overlays add environment context
- **Why two Postgres services**: Headless for StatefulSet DNS (stable identity), Primary for app connections (load balancing)
- **Why both startup + liveness probes**: Prevents restart loops during slow startup (Java/Keycloak can take 20+ seconds)
- **Why ConfigMap for init.sql**: Immutable config, easier than baked-into-image, updateable per environment

### Gotchas to Avoid

- Forgetting `serviceName` in StatefulSet causes pod DNS discovery failure (critical for Postgres)
- Missing headless service's `publishNotReadyAddresses: true` prevents pod-to-pod startup communication
- Keycloak startup probe timeout too short (<15s retries) causes premature restart loops
- `.NET health endpoints require HttpGet, not TCP probes (TCP only checks port, not app readiness)
- Ingress path `/api` must use `pathType: Prefix` to catch `/api/*` routes

### Next Steps

- Task 25: Create dev overlay (env-specific values, dev-db.postgres.svc, localhost ingress)
- Task 26: Create prod overlay (TLS config, resource limits, replica counts, PDB)
- Task 27: Add cert-manager + Let's Encrypt to prod
- Future: Network policies, pod disruption budgets, HPA (deferred to Wave 2)


---

## Task 5: Next.js 15 Project Initialization (2026-03-03)

### Key Learnings

1. **Next.js 15 with Bun Package Manager**
   - `bunx create-next-app@latest` with `--use-bun` flag successfully initializes projects
   - Bun installation 3-4x faster than npm/yarn (351 packages in 3.4s)
   - Next.js 16.1.6 (Turbopack) is default in create-next-app@latest (latest version)
   - Bun supports all Node.js ecosystem tools seamlessly
   - Dev server startup: 625ms ready time (excellent for development)

2. **shadcn/ui Integration**
   - Initialize with `bunx shadcn@latest init` (interactive prompt, sensible defaults)
   - Default color palette: Neutral (can override with slate, gray, zinc, stone)
   - CSS variables auto-generated in `src/app/globals.css` for theming
   - Components installed to `src/components/ui/` automatically
   - Note: `toast` component deprecated → use `sonner` instead (modern toast library)

3. **Standalone Output Configuration**
   - Set `output: 'standalone'` in `next.config.ts` for Docker deployments
   - Generates `.next/standalone/` with self-contained server.js entry point
   - Reduces Docker image size: only includes required node_modules (not full installation)
   - Production builds on this project: 2.9s compile, 240.4ms static page generation
   - Standalone directory structure: `.next/`, `node_modules/`, `server.js`, `package.json`

4. **TypeScript Path Aliases**
   - `@/*` → `./src/*` pre-configured in `tsconfig.json` by create-next-app
   - Enables clean imports: `import { Button } from '@/components/ui/button'`
   - Improves code readability, reduces relative path navigation (`../../`)
   - Compiler validates paths automatically (LSP support included)

5. **Directory Structure Best Practices**
   - App Router location: `src/app/` (not `pages/`)
   - Component organization: `src/components/` for reusable, `src/components/ui/` for shadcn
   - Utilities: `src/lib/` for helper functions (includes shadcn's `cn()` function)
   - Custom hooks: `src/hooks/` (prepared for future implementation)
   - Type definitions: `src/types/` (prepared for schema/type files)
   - This structure scales from MVP to enterprise applications

6. **Build Verification**
   - `bun run build` exit code 0, no errors
   - TypeScript type checking passes (via Next.js)
   - Static page generation: 4 pages (/, _not-found)
   - No build warnings or deprecations
   - Standalone build ready for Docker containerization

7. **Development Server Performance**
   - `bun run dev` startup: 625ms (ready state)
   - First page request: 1187ms (includes compilation + render)
   - Hot Module Reloading (HMR): Turbopack provides fast incremental updates
   - Bun's fast refresh cycles enable rapid development feedback
   - Note: Plan indicates Bun P99 SSR latency (340ms) vs Node.js (120ms), so production deployment will use Node.js

### shadcn/ui Components Installed

All 10 components successfully added to `src/components/ui/`:
- ✓ button.tsx — Base button component with variants (primary, secondary, etc.)
- ✓ card.tsx — Card layout container (Card, CardHeader, CardFooter, etc.)
- ✓ badge.tsx — Status badges with color variants
- ✓ input.tsx — Form input field with placeholder and error support
- ✓ label.tsx — Form label with accessibility attributes
- ✓ select.tsx — Dropdown select with options (Radix UI based)
- ✓ dialog.tsx — Modal dialog component (Alert Dialog pattern)
- ✓ dropdown-menu.tsx — Context menu/dropdown menu (Radix UI based)
- ✓ table.tsx — Data table with thead, tbody, rows
- ✓ sonner.tsx — Toast notifications (modern replacement for react-hot-toast)

All components use Tailwind CSS utilities, no custom CSS files needed.

### Environment Variables Configuration

Created `.env.local.example` (committed to git) with development defaults:
```
NEXT_PUBLIC_API_URL=http://localhost:5000        # Backend API endpoint
NEXTAUTH_URL=http://localhost:3000               # NextAuth callback URL
NEXTAUTH_SECRET=dev-secret-change-me             # Session encryption (Task 10)
KEYCLOAK_ISSUER=http://localhost:8080/realms/workclub  # OAuth2 discovery
KEYCLOAK_CLIENT_ID=workclub-app                  # Keycloak client ID
KEYCLOAK_CLIENT_SECRET=<from-keycloak>           # Placeholder (Task 3 fills in)
```

Pattern: `.env.local.example` is version-controlled, `.env.local` is gitignored per `.gitignore`.

### Dependencies Installed

```json
{
  "dependencies": {
    "next": "16.1.6",
    "react": "19.2.3",
    "react-dom": "19.2.3"
  },
  "devDependencies": {
    "@tailwindcss/postcss": "4.2.1",
    "@types/node": "20.19.35",
    "@types/react": "19.2.14",
    "@types/react-dom": "19.2.3",
    "eslint": "9.39.3",
    "eslint-config-next": "16.1.6",
    "tailwindcss": "4.2.1",
    "typescript": "5.9.3"
  }
}
```

Note: Intentionally minimal dependencies for MVP. NextAuth.js added in Task 10.

### Build & Runtime Verification

**Build Verification**: ✓ PASSED
- Command: `bun run build`
- Exit Code: 0
- Compilation: 2.9s (Turbopack)
- TypeScript: No errors
- Static Generation: 4 pages in 240.4ms
- Output: `.next/standalone/` with all required files

**Dev Server Verification**: ✓ PASSED
- Command: `bun run dev`
- Startup: 625ms to ready state
- Port: 3000 (accessible)
- HTTP GET /: 200 OK in 1187ms
- Server process: Graceful shutdown with SIGTERM

**Standalone Verification**: ✓ PASSED
- `.next/standalone/server.js`: 6.55 KB entry point
- `.next/standalone/node_modules/`: Self-contained dependencies
- `.next/standalone/package.json`: Runtime configuration
- `.next/` directory: Pre-built routes and static assets

### Patterns & Conventions

1. **Component Organization**:
   - UI components: `src/components/ui/` (shadcn)
   - Feature components: `src/components/features/` (future)
   - Layout components: `src/components/layout/` (future)
   - Avoid nested folders beyond 2 levels for discoverability

2. **TypeScript Strict Mode**:
   - `tsconfig.json` includes `"strict": true`
   - All variables require explicit types
   - Enables IDE autocomplete and early error detection

3. **Tailwind CSS v4 Configuration**:
   - Uses CSS variables for theming (shadcn standard)
   - Tailwind config auto-generated by shadcn init
   - No custom color palette yet (uses defaults from Neutral)

4. **Git Strategy**:
   - `.env.local.example` is committed (template for developers)
   - `.env.local` is in `.gitignore` (personal configurations)
   - No node_modules/ in repo (installed via `bun install`)

### Configuration Files Created

- `frontend/next.config.ts` — Minimal, standalone output enabled
- `frontend/tsconfig.json` — Path aliases, strict TypeScript mode
- `frontend/.env.local.example` — Environment variable template
- `frontend/components.json` — shadcn/ui configuration
- `frontend/tailwind.config.ts` — Tailwind CSS configuration with Tailwind v4
- `frontend/postcss.config.js` — PostCSS configuration for Tailwind

### Next Steps & Dependencies

- **Task 10**: NextAuth.js integration
  - Adds `next-auth` dependency
  - Creates `src/app/api/auth/[...nextauth]/route.ts`
  - Integrates with Keycloak (configured in Task 3)

- **Task 17**: Frontend test infrastructure
  - Adds vitest, @testing-library/react
  - Component tests for shadcn/ui wrapper components
  - E2E tests with Playwright (already in docker-compose)

- **Task 18**: Layout and authentication UI
  - Creates `src/app/layout.tsx` with navbar/sidebar
  - Client-side session provider setup
  - Login/logout flows

- **Task 21**: Club management interface
  - Feature components in `src/components/features/`
  - Forms using shadcn input/select/button
  - Data fetching from backend API (Task 6+)

### Gotchas to Avoid

1. **Bun vs Node.js Distinction**: This project uses Bun for development (fast HMR, 625ms startup). Production deployment will use Node.js due to P99 latency concerns (documented in plan).

2. **shadcn/ui Component Customization**: Components are meant to be copied and modified for project-specific needs. Avoid creating wrapper components — extend the shadcn components directly.

3. **Environment Variables Naming**: 
   - `NEXT_PUBLIC_*` are exposed to browser (use only for client-safe values)
   - `KEYCLOAK_CLIENT_SECRET` is server-only (never exposed to frontend)
   - `.env.local` for local development, CI/CD environment variables at deployment

4. **Path Aliases in Dynamic Imports**: If using dynamic imports with `next/dynamic`, ensure paths use `@/*` syntax for alias resolution.

5. **Tailwind CSS v4 Breaking Changes**: 
   - Requires `@tailwindcss/postcss` package (not default tailwindcss)
   - CSS layer imports may differ from v3 (auto-handled by create-next-app)

### Evidence & Artifacts

- Build output: `.sisyphus/evidence/task-5-nextjs-build.txt`
- Dev server output: `.sisyphus/evidence/task-5-dev-server.txt`
- Git commit: `chore(frontend): initialize Next.js project with Tailwind and shadcn/ui`

## Task 3: Keycloak Realm Configuration (2026-03-03)

### Key Learnings

1. **Keycloak Realm Export Structure**
   - Realm exports are JSON files with top-level keys: `realm`, `clients`, `users`, `roles`, `groups`
   - Must include `enabled: true` for realm and clients to be active on import
   - Version compatibility: Export from Keycloak 26.x is compatible with 26.x imports
   - Import command: `start-dev --import-realm` (Docker volume mount required)

2. **Protocol Mapper Configuration for Custom JWT Claims**
   - Mapper type: `oidc-usermodel-attribute-mapper` (NOT Script Mapper)
   - Critical setting: `jsonType.label: JSON` ensures claim is parsed as JSON object (not string)
   - User attribute: `clubs` (custom attribute on user entity)
   - Token claim name: `clubs` (appears in JWT payload)
   - Must include in: ID token, access token, userinfo endpoint (all three flags set to true)
   - Applied to both clients: workclub-api and workclub-app (defined in client protocolMappers array)

3. **Client Configuration Patterns**
   - **Confidential client (workclub-api)**:
     - `publicClient: false`, has client secret
     - `serviceAccountsEnabled: true` for service-to-service auth
     - `standardFlowEnabled: false`, `directAccessGrantsEnabled: false` (no user login)
     - Used by backend for client credentials grant
   - **Public client (workclub-app)**:
     - `publicClient: true`, no client secret
     - `standardFlowEnabled: true` for OAuth2 Authorization Code Flow
     - `directAccessGrantsEnabled: true` (enables password grant for dev testing)
     - PKCE enabled via `attributes.pkce.code.challenge.method: S256`
     - Redirect URIs: `http://localhost:3000/*` (wildcard for dev)
     - Web origins: `http://localhost:3000` (CORS configuration)

4. **User Configuration with Custom Attributes**
   - Custom attribute format: `attributes.clubs: ["{\"club-1-uuid\": \"admin\"}"]`
   - Attribute value is array of strings (even for single value)
   - JSON must be escaped as string in user attributes
   - Protocol mapper will parse this string as JSON when generating JWT claim
   - Users must have: `enabled: true`, `emailVerified: true`, no `requiredActions: []`

5. **Password Hashing in Realm Exports**
   - Algorithm: `pbkdf2-sha512` (Keycloak default)
   - Hash iterations: 210000 (high security for dev environment)
   - Credentials structure includes: `hashedSaltedValue`, `salt`, `hashIterations`, `algorithm`
   - Password: `testpass123` (all test users use same password for simplicity)
   - Note: Hashed values in this export are PLACEHOLDER — Keycloak will generate real hashes on first user creation

6. **Multi-Tenant Club Membership Data Model**
   - Format: `{"<tenant-id>": "<role>"}`
   - Example: `{"club-1-uuid": "admin", "club-2-uuid": "member"}`
   - Keys: Club UUIDs (tenant identifiers)
   - Values: Role strings (admin, manager, member, viewer)
   - Users can belong to multiple clubs with different roles in each
   - Placeholder UUIDs used: `club-1-uuid`, `club-2-uuid` (real UUIDs created in Task 11 seed data)

7. **Test User Scenarios**
   - **admin@test.com**: Multi-club admin (admin in club-1, member in club-2)
   - **manager@test.com**: Single club manager (manager in club-1)
   - **member1@test.com**: Multi-club member (member in both clubs)
   - **member2@test.com**: Single club member (member in club-1)
   - **viewer@test.com**: Read-only viewer (viewer in club-1)
   - Covers all role types and single/multi-club scenarios

8. **Docker Environment Configuration**
   - Keycloak 26.1 runs in Docker container
   - Realm import via volume mount: `./infra/keycloak:/opt/keycloak/data/import`
   - Health check endpoint: `/health/ready`
   - Token endpoint: `/realms/workclub/protocol/openid-connect/token`
   - Admin credentials: `admin/admin` (for Keycloak admin console)

9. **JWT Token Testing Approach**
   - Use password grant (Direct Access Grant) for testing: `grant_type=password&username=...&password=...&client_id=workclub-app`
   - Decode JWT: Split on `.`, extract second part (payload), base64 decode, parse JSON
   - Verify claim type: `jq -r '.clubs | type'` should return `object` (NOT `string`)
   - Test script: `infra/keycloak/test-auth.sh` automates this verification

10. **Common Pitfalls Avoided**
    - DO NOT use Script Mapper (complex, requires JavaScript, harder to debug)
    - DO NOT use `jsonType.label: String` (will break multi-tenant claim parsing)
    - DO NOT forget `multivalued: false` in protocol mapper (we want single JSON object, not array)
    - DO NOT hardcode real UUIDs in test users (use placeholders, seed data creates real IDs)
    - DO NOT export realm without users (need `--users realm_file` or admin UI export with users enabled)

### Configuration Files Created

- **infra/keycloak/realm-export.json**: Complete realm configuration (8.9 KB)
- **infra/keycloak/test-auth.sh**: Automated verification script for JWT claims
- **.sisyphus/evidence/task-3-verification.txt**: Detailed verification documentation
- **.sisyphus/evidence/task-3-user-auth.txt**: User authentication results (placeholder)
- **.sisyphus/evidence/task-3-jwt-claims.txt**: JWT claim structure documentation (placeholder)

### Docker Environment Issue

- Colima (Docker runtime on macOS) failed to start with VZ driver error
- Verification deferred until Docker environment is available
- All configuration files are complete and JSON-validated
- Test script is ready for execution when Docker is running

### Next Phase Considerations

- Task 8 (Finbuckle) will consume `clubs` claim to implement tenant resolution
- Task 9 (JWT auth middleware) will validate tokens from Keycloak
- Task 10 (NextAuth) will use workclub-app client for frontend authentication
- Task 11 (seed data) will replace placeholder UUIDs with real club IDs
- Production deployment will need: real client secrets, HTTPS redirect URIs, proper password policies