feat: Add project foundation, documentation, and Docker setup

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2026-01-19 19:49:47 +01:00
commit a59ef0f3f5
10 changed files with 1020 additions and 0 deletions
--- a/README.md
+++ b/README.md
@@ -0,0 +1,228 @@
 # Training Tracker
 A mobile-friendly web application for tracking training activities with a Go backend and PostgreSQL database.
 ## Project Structure
 ```
 training-tracker/
 ├── backend/
 │   ├── cmd/server/         # Application entry point
 │   ├── internal/
 │   │   ├── api/            # HTTP handlers
 │   │   ├── models/         # Data structures
 │   │   └── storage/        # Database layer
 │   ├── Dockerfile.dev      # Development container
 │   ├── Dockerfile.prod     # Production container
 │   ├── go.mod
 │   └── go.sum
 ├── frontend/
 │   ├── index.html
 │   ├── css/styles.css
 │   └── js/
 │       ├── api.js          # API client
 │       └── app.js          # Application logic
 ├── .gitea/workflows/       # CI/CD pipelines
 ├── docker-compose.yml
 └── README.md
 ```
 ## Prerequisites
 - Docker and Docker Compose
 - Go 1.25.6+ (for local development without Docker)
 - A web server or `python3 -m http.server` (for frontend)
 ## Running with Docker Compose (Recommended)
 Start PostgreSQL and the backend:
 ```bash
 docker-compose up -d
 ```
 This starts:
 - PostgreSQL on port 5432
 - Backend API on port 8080
 To view logs:
 ```bash
 docker-compose logs -f backend
 ```
 To stop:
 ```bash
 docker-compose down
 ```
 ## Running Manually
 ### 1. Start PostgreSQL
 ```bash
 docker-compose up -d postgres
 ```
 Or use an existing PostgreSQL instance and set environment variables.
 ### 2. Run the Backend
 ```bash
 cd backend
 export DB_HOST=localhost
 export DB_PORT=5432
 export DB_USER=postgres
 export DB_PASSWORD=postgres
 export DB_NAME=training_tracker
 go run ./cmd/server
 ```
 ### 3. Serve the Frontend
 ```bash
 cd frontend
 python3 -m http.server 3000
 ```
 Open http://localhost:3000 in your browser.
 ## Testing
 The backend includes comprehensive unit and integration tests.
 ### Run Unit Tests
 ```bash
 cd backend
 go test ./...
 ```
 ### Run Tests with Coverage
 ```bash
 cd backend
 go test -cover ./...
 ```
 ### Run Integration Tests
 Integration tests use testcontainers to spin up a PostgreSQL instance. Docker must be running.
 ```bash
 cd backend
 go test -v -tags=integration ./internal/storage/...
 ```
 ### Run All Tests
 ```bash
 cd backend
 go test ./... && go test -tags=integration ./internal/storage/...
 ```
 ## Environment Variables
 | Variable | Default | Description |
 |----------|---------|-------------|
 | `DB_HOST` | localhost | PostgreSQL host |
 | `DB_PORT` | 5432 | PostgreSQL port |
 | `DB_USER` | postgres | Database user |
 | `DB_PASSWORD` | postgres | Database password |
 | `DB_NAME` | training_tracker | Database name |
 | `PORT` | 8080 | Backend server port |
 ## API Endpoints
 ### Exercises
 | Method | Endpoint | Description |
 |--------|----------|-------------|
 | GET | `/api/exercises` | List all exercises |
 | POST | `/api/exercises` | Create exercise |
 | GET | `/api/exercises/:id` | Get exercise by ID |
 | PUT | `/api/exercises/:id` | Update exercise |
 | DELETE | `/api/exercises/:id` | Delete exercise |
 ### Training Plans
 | Method | Endpoint | Description |
 |--------|----------|-------------|
 | GET | `/api/plans` | List all plans |
 | POST | `/api/plans` | Create plan |
 | GET | `/api/plans/:id` | Get plan with exercises |
 | PUT | `/api/plans/:id` | Update plan |
 | DELETE | `/api/plans/:id` | Delete plan |
 ### Sessions
 | Method | Endpoint | Description |
 |--------|----------|-------------|
 | GET | `/api/sessions` | List all sessions |
 | POST | `/api/sessions` | Create session |
 | GET | `/api/sessions/:id` | Get session with entries |
 | PUT | `/api/sessions/:id` | Update session |
 | DELETE | `/api/sessions/:id` | Delete session |
 | POST | `/api/sessions/:id/entries` | Add exercise entry |
 ### Health Check
 | Method | Endpoint | Description |
 |--------|----------|-------------|
 | GET | `/api/health` | Returns `{"status": "ok"}` |
 ## API Examples
 ### Create an Exercise
 ```bash
 curl -X POST http://localhost:8080/api/exercises \
  -H "Content-Type: application/json" \
  -d '{"name": "Bench Press", "type": "strength", "muscle_group": "Chest"}'
 ```
 ### Create a Session
 ```bash
 curl -X POST http://localhost:8080/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"date": "2026-01-19T10:00:00Z", "notes": "Morning workout"}'
 ```
 ### Add Entry to Session
 ```bash
 curl -X POST http://localhost:8080/api/sessions/1/entries \
  -H "Content-Type: application/json" \
  -d '{"exercise_id": 1, "weight": 80, "sets_completed": 3, "reps": 10}'
 ```
 ## Features
 - Mobile-first responsive design
 - Exercise library (strength and cardio types)
 - Training plan templates
 - Session logging with:
  - Strength: weight, sets, reps
  - Cardio: duration, distance, heart rate
 - Session history and dashboard
 ## Production Deployment
 Build the production image:
 ```bash
 docker build -f backend/Dockerfile.prod -t training-tracker-backend ./backend
 ```
 The production image uses:
 - Distroless base image
 - Non-root user
 - Pinned image digests for reproducibility
 ## CI/CD
 The project includes a Gitea Actions workflow (`.gitea/workflows/ci.yaml`) that:
 1. Runs tests on pull requests
 2. Builds and pushes Docker images on merge to main
--- a/backend/Dockerfile.dev
+++ b/backend/Dockerfile.dev
@@ -0,0 +1,18 @@
 FROM golang:1.25.6-bookworm
 WORKDIR /app
 RUN apt-get update && apt-get install -y --no-install-recommends \
    git \
    && rm -rf /var/lib/apt/lists/*
 COPY go.mod go.sum ./
 RUN go mod download
 COPY . .
 RUN go build -o server ./cmd/server
 EXPOSE 8080
 CMD ["./server"]
--- a/backend/Dockerfile.prod
+++ b/backend/Dockerfile.prod
@@ -0,0 +1,22 @@
 # Production Dockerfile with pinned image digests
 # golang:1.25.6-alpine
 FROM golang@sha256:d9b2e14101f27ec8d09674cd01186798d227bb0daec90e032aeb1cd22ac0f029 AS builder
 WORKDIR /app
 COPY go.mod go.sum ./
 RUN go mod download
 COPY . .
 RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-s -w" -o server ./cmd/server
 # gcr.io/distroless/static-debian12:nonroot
 FROM gcr.io/distroless/static-debian12@sha256:6dcc833df2a475be1a3d7fc951de90ac91a2cb0be237c7578b88722571f77571
 COPY --from=builder /app/server /server
 USER nonroot:nonroot
 EXPOSE 8080
 ENTRYPOINT ["/server"]
--- a/backend/claude.md
+++ b/backend/claude.md
@@ -0,0 +1,116 @@
 ## General
 - Before scaffolding any service, verify current stable versions from official sources (go.dev, rust-lang.org, nodejs.org, etc.)
 - Prefer stdlib over dependencies where reasonable
 - No vendoring unless explicitly requested
 ## Go
 - Use latest stable Go version (check https://go.dev/dl/ before starting)
 - Use `slog` for structured logging
 - `context.Context` first param, always
 - No `init()` unless unavoidable
 - Errors: prefer `errors.Join` for multiple errors, `fmt.Errorf` with `%w` for wrapping
 ## Containers
 - Multi-stage builds, distroless/scratch final images
 - ubuntu based images for the development builds
 - Non-root user, read-only rootfs for production builds
 - prepare dockerfiles for both development and production
 - Pin base image digests in prod Dockerfiles
 ## K8s Manifests
 - Always include resource requests/limits
 - Liveness/readiness probes with sane defaults
 - PodDisruptionBudgets for replicated workloads
 ## Code Style
 - Fail fast, return early
 - Table-driven tests
 - No obvious comments
 ## CI/CD
 - Git remote: Gitea at https://[gitea.yourdomain.com](https://gitea.home.hrajfrisbee.cz/)
 - CI: Gitea Actions (workflow syntax is GitHub Actions compatible)
 - Workflows go in `.gitea/workflows/`
 - Use `runs-on: linux-amd64` (or whatever labels your runners have)
 - Registry: gitea.home.hrajfrisbee.cz (use `${{ secrets.REGISTRY_TOKEN }}` for auth)
 ## Testing (Go)
 ### Go Test Requirements
 - **MANDATORY: All new Go code must have corresponding tests**
 - Use stdlib `testing` package, no testify unless already in project
 - Table-driven tests as default pattern
 - Test file next to source: `foo.go` → `foo_test.go`
 - Name tests `Test<Function>_<scenario>` (e.g., `TestCreateUser_duplicateEmail`)
 - Use `t.Parallel()` where safe
 - Subtests for table entries: `t.Run(tc.name, func(t *testing.T) { ... })`
 - Test behavior, not implementation
 - Use `testing.Short()` to skip slow integration tests: `if testing.Short() { t.Skip() }`
 ### Test Structure
 - Each test function should test ONE behavior
 - Use descriptive test names: `TestExerciseHandler_Create_ValidInput`
 - Table-driven test format:
  ```go
  tests := []struct {
      name    string
      input   InputType
      want    ExpectedType
      wantErr bool
  }{
      {"valid input", validInput, expectedOutput, false},
      {"empty name", emptyName, nil, true},
  }
  for _, tt := range tests {
      t.Run(tt.name, func(t *testing.T) {
          // test logic
      })
  }
  ```
 ### Handler Tests (Unit)
 - Mock external dependencies (repositories, services)
 - Use `httptest.NewRecorder()` and `httptest.NewRequest()`
 - Test: success path, validation errors, not found, internal errors
 - Mock interfaces defined in `internal/api/interfaces.go`
 - Mock implementations in `internal/api/mocks_test.go`
 ### Repository Tests (Integration)
 - Use testcontainers-go for database tests
 - Integration tests in `_test.go` with build tag `//go:build integration`
 - Clean database state between tests using `truncateTables()`
 - Test: CRUD operations, edge cases, transactions, cascades
 - Test helpers in `internal/storage/testhelpers_test.go`
 ### What to Test
 - All public functions/methods
 - Happy path AND error paths
 - Edge cases: empty inputs, nil values, not found
 - Validation logic
 - Transaction rollback scenarios
 ### What NOT to Test
 - Simple getters/setters
 - Third-party library code
 - Private helper functions (test through public API)
 ### Running Tests
 ```bash
 # Run all unit tests (fast)
 go test ./...
 # Run with verbose output
 go test -v ./...
 # Run with coverage
 go test -cover ./...
 # Run only unit tests, skip integration
 go test -short ./...
 # Run integration tests (requires Docker)
 go test -v -tags=integration ./internal/storage/...
 # Run specific package
 go test -v ./internal/api/...
 ```
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -0,0 +1,67 @@
 module training-tracker
 go 1.25.6
 require (
 	github.com/lib/pq v1.10.9
 	github.com/testcontainers/testcontainers-go v0.40.0
 	github.com/testcontainers/testcontainers-go/modules/postgres v0.40.0
 )
 require (
 	dario.cat/mergo v1.0.2 // indirect
 	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
 	github.com/containerd/errdefs v1.0.0 // indirect
 	github.com/containerd/errdefs/pkg v0.3.0 // indirect
 	github.com/containerd/log v0.1.0 // indirect
 	github.com/containerd/platforms v0.2.1 // indirect
 	github.com/cpuguy83/dockercfg v0.3.2 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/distribution/reference v0.6.0 // indirect
 	github.com/docker/docker v28.5.1+incompatible // indirect
 	github.com/docker/go-connections v0.6.0 // indirect
 	github.com/docker/go-units v0.5.0 // indirect
 	github.com/ebitengine/purego v0.8.4 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/go-logr/logr v1.4.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.4 // indirect
 	github.com/klauspost/compress v1.18.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/magiconair/properties v1.8.10 // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
 	github.com/moby/go-archive v0.1.0 // indirect
 	github.com/moby/patternmatcher v0.6.0 // indirect
 	github.com/moby/sys/sequential v0.6.0 // indirect
 	github.com/moby/sys/user v0.4.0 // indirect
 	github.com/moby/sys/userns v0.1.0 // indirect
 	github.com/moby/term v0.5.0 // indirect
 	github.com/morikuni/aec v1.0.0 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.1.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
 	github.com/shirou/gopsutil/v4 v4.25.6 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/stretchr/testify v1.11.1 // indirect
 	github.com/tklauser/go-sysconf v0.3.12 // indirect
 	github.com/tklauser/numcpus v0.6.1 // indirect
 	github.com/yusufpapurcu/wmi v1.2.4 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.49.0 // indirect
 	go.opentelemetry.io/otel v1.38.0 // indirect
 	go.opentelemetry.io/otel/metric v1.38.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.38.0 // indirect
 	go.opentelemetry.io/otel/trace v1.38.0 // indirect
 	golang.org/x/crypto v0.43.0 // indirect
 	golang.org/x/sys v0.38.0 // indirect
 	golang.org/x/text v0.32.0 // indirect
 	google.golang.org/grpc v1.78.0 // indirect
 	google.golang.org/protobuf v1.36.11 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
--- a/backend/go.sum
+++ b/backend/go.sum
@@ -0,0 +1,178 @@
 dario.cat/mergo v1.0.2 h1:85+piFYR1tMbRrLcDwR18y4UKJ3aH1Tbzi24VRW1TK8=
 dario.cat/mergo v1.0.2/go.mod h1:E/hbnu0NxMFBjpMIE34DRGLWqDy0g5FuKDhCb31ngxA=
 github.com/AdaLogics/go-fuzz-headers v0.0.0-20240806141605-e8a1dd7889d6 h1:He8afgbRMd7mFxO99hRNu+6tazq8nFF9lIwo9JFroBk=
 github.com/AdaLogics/go-fuzz-headers v0.0.0-20240806141605-e8a1dd7889d6/go.mod h1:8o94RPi1/7XTJvwPpRSzSUedZrtlirdB3r9Z20bi2f8=
 github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 h1:UQHMgLO+TxOElx5B5HZ4hJQsoJ/PvUvKRhJHDQXO8P8=
 github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1/go.mod h1:xomTg63KZ2rFqZQzSB4Vz2SUXa1BpHTVz9L5PTmPC4E=
 github.com/Microsoft/go-winio v0.6.2 h1:F2VQgta7ecxGYO8k3ZZz3RS8fVIXVxONVUPlNERoyfY=
 github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA8Ipt1oGCvU=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
 github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
 github.com/containerd/errdefs v1.0.0 h1:tg5yIfIlQIrxYtu9ajqY42W3lpS19XqdxRQeEwYG8PI=
 github.com/containerd/errdefs v1.0.0/go.mod h1:+YBYIdtsnF4Iw6nWZhJcqGSg/dwvV7tyJ/kCkyJ2k+M=
 github.com/containerd/errdefs/pkg v0.3.0 h1:9IKJ06FvyNlexW690DXuQNx2KA2cUJXx151Xdx3ZPPE=
 github.com/containerd/errdefs/pkg v0.3.0/go.mod h1:NJw6s9HwNuRhnjJhM7pylWwMyAkmCQvQ4GpJHEqRLVk=
 github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
 github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3EhrzVo=
 github.com/containerd/platforms v0.2.1 h1:zvwtM3rz2YHPQsF2CHYM8+KtB5dvhISiXh5ZpSBQv6A=
 github.com/containerd/platforms v0.2.1/go.mod h1:XHCb+2/hzowdiut9rkudds9bE5yJ7npe7dG/wG+uFPw=
 github.com/cpuguy83/dockercfg v0.3.2 h1:DlJTyZGBDlXqUZ2Dk2Q3xHs/FtnooJJVaad2S9GKorA=
 github.com/cpuguy83/dockercfg v0.3.2/go.mod h1:sugsbF4//dDlL/i+S+rtpIWp+5h0BHJHfjj5/jFyUJc=
 github.com/creack/pty v1.1.18 h1:n56/Zwd5o6whRC5PMGretI4IdRLlmBXYNjScPaBgsbY=
 github.com/creack/pty v1.1.18/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/distribution/reference v0.6.0 h1:0IXCQ5g4/QMHHkarYzh5l+u8T3t73zM5QvfrDyIgxBk=
 github.com/distribution/reference v0.6.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
 github.com/docker/docker v28.5.1+incompatible h1:Bm8DchhSD2J6PsFzxC35TZo4TLGR2PdW/E69rU45NhM=
 github.com/docker/docker v28.5.1+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.6.0 h1:LlMG9azAe1TqfR7sO+NJttz1gy6KO7VJBh+pMmjSD94=
 github.com/docker/go-connections v0.6.0/go.mod h1:AahvXYshr6JgfUJGdDCs2b5EZG/vmaMAntpSFH5BFKE=
 github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
 github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
 github.com/ebitengine/purego v0.8.4 h1:CF7LEKg5FFOsASUj0+QwaXf8Ht6TlFxg09+S9wz0omw=
 github.com/ebitengine/purego v0.8.4/go.mod h1:iIjxzd6CiRiOG0UyXP+V1+jWqUXVjPKLAI0mRfJZTmQ=
 github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
 github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/go-ole/go-ole v1.2.6 h1:/Fpf6oFPoeFik9ty7siob0G6Ke8QvQEuVcuChpwXzpY=
 github.com/go-ole/go-ole v1.2.6/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=
 github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
 github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.4 h1:kEISI/Gx67NzH3nJxAmY/dGac80kKZgZt134u7Y/k1s=
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.4/go.mod h1:6Nz966r3vQYCqIzWsuEl9d7cf7mRhtDmm++sOxlnfxI=
 github.com/jackc/pgpassfile v1.0.0 h1:/6Hmqy13Ss2zCq62VdNG8tM1wchn8zjSGOBJ6icpsIM=
 github.com/jackc/pgpassfile v1.0.0/go.mod h1:CEx0iS5ambNFdcRtxPj5JhEz+xB6uRky5eyVu/W2HEg=
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 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
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 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools/v3 v3.5.2 h1:7koQfIKdy+I8UTetycgUqXWSDwpgv193Ka+qRsmBY8Q=
 gotest.tools/v3 v3.5.2/go.mod h1:LtdLGcnqToBH83WByAAi/wiwSFCArdFIUV/xxN4pcjA=
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -0,0 +1,40 @@
 version: '3.8'
 services:
  postgres:
    image: postgres:15-alpine
    container_name: training-tracker-db
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: training_tracker
    ports:
      - "5432:5432"
    volumes:
      - postgres_data:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 5s
      timeout: 5s
      retries: 5
  backend:
    build:
      context: ./backend
      dockerfile: Dockerfile.dev
    container_name: training-tracker-backend
    environment:
      DB_HOST: postgres
      DB_PORT: 5432
      DB_USER: postgres
      DB_PASSWORD: postgres
      DB_NAME: training_tracker
      PORT: 8080
    ports:
      - "8080:8080"
    depends_on:
      postgres:
        condition: service_healthy
 volumes:
  postgres_data:
--- a/plans/001-initial-implementation-plan.md
+++ b/plans/001-initial-implementation-plan.md
@@ -0,0 +1,186 @@
 # Training Tracker - Implementation Plan
 ## Project Overview
 A mobile-friendly web application for tracking training activities with a Golang backend and SQL/NoSQL database.
 ---
 ## Phase 1: Project Foundation
 ### 1.1 Project Structure
 ```
 training-tracker/
 ├── backend/
 │   ├── cmd/
 │   │   └── server/
 │   │       └── main.go
 │   ├── internal/
 │   │   ├── api/           # HTTP handlers
 │   │   ├── models/        # Data structures
 │   │   ├── storage/       # Database layer
 │   │   └── service/       # Business logic
 │   ├── go.mod
 │   └── go.sum
 ├── frontend/
 │   ├── index.html
 │   ├── css/
 │   │   └── styles.css
 │   ├── js/
 │   │   ├── app.js
 │   │   ├── api.js
 │   │   └── components/
 │   └── assets/
 ├── docker-compose.yml
 └── readme.md
 ```
 ### 1.2 Database Schema Design
 **Core entities:**
 - **users** - User accounts (id, username, email, password_hash, created_at)
 - **exercises** - Exercise definitions (id, name, type, muscle_group, description)
 - **training_plans** - Training plan templates (id, user_id, name, description)
 - **plan_exercises** - Exercises in a plan (id, plan_id, exercise_id, sets, reps, duration, order)
 - **sessions** - Completed training sessions (id, user_id, plan_id, date, notes)
 - **session_entries** - Individual exercise entries (id, session_id, exercise_id, weight, reps, duration, sets_completed)
 **Choice:** PostgreSQL (can use Docker for local development)
 ---
 ## Phase 2: Backend Development (Golang)
 ### 2.1 Initial Setup
 - Initialize Go module
 - Set up HTTP router (standard library `net/http` or `chi`/`gorilla/mux`)
 - Configure environment variables
 - Set up database connection
 ### 2.2 API Endpoints
 ```
 # Auth endpoints (deferred to v2)
 # POST   /api/auth/register
 # POST   /api/auth/login
 Exercises:
  GET    /api/exercises          # List all exercises
  POST   /api/exercises          # Create exercise
  GET    /api/exercises/:id      # Get exercise
  PUT    /api/exercises/:id      # Update exercise
  DELETE /api/exercises/:id      # Delete exercise
 Training Plans:
  GET    /api/plans              # List user's plans
  POST   /api/plans              # Create plan
  GET    /api/plans/:id          # Get plan with exercises
  PUT    /api/plans/:id          # Update plan
  DELETE /api/plans/:id          # Delete plan
 Sessions:
  GET    /api/sessions           # List sessions (with filters)
  POST   /api/sessions           # Create/start session
  GET    /api/sessions/:id       # Get session details
  PUT    /api/sessions/:id       # Update session
  DELETE /api/sessions/:id       # Delete session
  POST   /api/sessions/:id/entries  # Add entry to session
 ```
 ### 2.3 Core Backend Tasks
 1. Set up Go project structure and dependencies
 2. Set up PostgreSQL via Docker
 3. Implement database migrations
 4. Create data models and repository layer
 5. Implement REST API handlers
 6. Add input validation and error handling
 7. Implement CORS for frontend communication
 8. (v2) Add authentication
 ---
 ## Phase 3: Frontend Development (HTML/CSS/JS)
 ### 3.1 Mobile-First Design
 - Responsive CSS with mobile breakpoints
 - Touch-friendly UI elements
 - Offline-capable design (future PWA)
 ### 3.2 Core Views/Pages
 1. **Dashboard** - Overview of recent sessions, quick actions
 2. **Training Plan View** - Display exercises for current session
 3. **Session Logger** - Form to enter weights/reps/duration during workout
   - Strength: weight, sets, reps
   - Cardio: duration, distance, heart rate (optional)
 4. **History** - View past sessions and progress
 5. **Exercise Library** - Browse and manage exercises
 6. (v2) **Login/Register** - Authentication screens
 ### 3.3 Frontend Tasks
 1. Create base HTML structure and navigation
 2. Implement responsive CSS (flexbox/grid)
 3. Build API client module (fetch wrapper)
 4. Create reusable UI components
 5. Implement session logging interface
 6. Add form validation
 7. Implement local storage for offline data entry
 ---
 ## Phase 4: Integration & Testing
 ### 4.1 Integration
 - Connect frontend to backend API
 - Test all CRUD operations
 - Handle loading states and errors
 - Implement authentication flow
 ### 4.2 Testing
 - Backend: Unit tests for handlers and services
 - Frontend: Manual testing on mobile devices
 - API: Integration tests
 ---
 ## Phase 5: Deployment (Optional for v1)
 - Docker containerization
 - Docker Compose for local development
 - Basic deployment documentation
 ---
 ## Future Enhancements (v2+)
 - Strava integration
 - Whoop integration
 - Progress charts and analytics
 - Workout timer
 - PWA with offline support
 - Export data (CSV/PDF)
 ---
 ## Recommended Implementation Order
 1. **Backend foundation** - Go project setup, PostgreSQL via Docker, basic models
 2. **Core API** - Exercises and sessions endpoints (strength + cardio support)
 3. **Frontend skeleton** - HTML structure, CSS, navigation
 4. **Session logging** - The core feature (enter workout data)
 5. **Training plans** - Plan viewing and management
 6. **Polish** - Error handling, validation, UX improvements
 7. (v2) **Authentication** - User accounts
 ---
 ## Decisions Made
 - **Database**: PostgreSQL (via Docker for local dev)
 - **Authentication**: None initially (single-user mode), add in v2
 - **Exercise types**: Both strength (weight/sets/reps) and cardio (duration/distance/HR)
 ## Verification
 After implementation, verify by:
 1. Start PostgreSQL container and backend server
 2. Open frontend in browser (mobile viewport)
 3. Create a test exercise (e.g., "Bench Press" - strength type)
 4. Create a training plan with exercises
 5. Log a session with actual data entry
 6. View session history
--- a/plans/testing-plan.md
+++ b/plans/testing-plan.md
@@ -0,0 +1,152 @@
 # Backend Testing Plan
 ## Overview
 Add comprehensive tests for the training-tracker backend following Go best practices and the CLAUDE.md guidelines (table-driven tests).
 **Scope:** Both unit tests (handlers with mocks) AND integration tests (repositories with testcontainers)
 **Plan storage:** Copy this plan to `training-tracker/plans/testing-plan.md`
 ## Current State
 - **No existing tests** - greenfield testing
 - 3 packages to test: `api`, `storage`, `models`
 - Dependencies: handlers → repositories → database
 ## Testing Strategy
 ### 1. Unit Tests for API Handlers
 Test HTTP handlers with mocked repositories.
 **Files to create:**
 - `internal/api/exercises_test.go`
 - `internal/api/plans_test.go`
 - `internal/api/sessions_test.go`
 **Approach:**
 - Define repository interfaces
 - Create mock implementations
 - Use `httptest.NewRecorder()` and `httptest.NewRequest()`
 - Table-driven tests for each endpoint
 **Test cases per handler:**
 - List: empty result, multiple results
 - GetByID: found, not found
 - Create: valid input, missing required fields, invalid type
 - Update: found, not found, validation errors
 - Delete: found, not found
 ### 2. Integration Tests for Storage Layer
 Test repositories against real PostgreSQL using testcontainers.
 **Files to create:**
 - `internal/storage/exercises_test.go`
 - `internal/storage/plans_test.go`
 - `internal/storage/sessions_test.go`
 - `internal/storage/db_test.go`
 **Approach:**
 - Use `testcontainers-go` to spin up PostgreSQL
 - Run migrations before tests
 - Test CRUD operations end-to-end
 - Test transaction rollback scenarios
 **Test cases:**
 - CRUD operations for each entity
 - Cascading deletes
 - Transaction handling in plans (create/update)
 - NULL field handling
 - Foreign key constraints
 ### 3. Test File Structure
 ```
 backend/internal/
 ├── api/
 │   ├── exercises_test.go
 │   ├── plans_test.go
 │   ├── sessions_test.go
 │   └── mocks_test.go        # Shared mock implementations
 ├── storage/
 │   ├── testhelpers_test.go  # Shared test database setup
 │   ├── exercises_test.go
 │   ├── plans_test.go
 │   └── sessions_test.go
 └── models/
    └── (no tests needed - pure data structures)
 ```
 ## Implementation Steps
 1. **Create plans folder** and store this plan:
   - Create `training-tracker/plans/`
   - Copy this plan to `training-tracker/plans/testing-plan.md`
 2. **Add test dependencies** to go.mod:
   - `github.com/testcontainers/testcontainers-go`
   - Use standard library for assertions (no testify)
 3. **Create repository interfaces** in `internal/api/`:
   - `ExerciseRepository` interface
   - `PlanRepository` interface
   - `SessionRepository` interface
 4. **Create mock implementations** for unit testing handlers
 5. **Create test helpers** for integration tests:
   - Shared PostgreSQL container setup
   - Database cleanup between tests
 6. **Write handler unit tests** (table-driven):
   - All CRUD operations
   - Validation error paths
   - Not found scenarios
 7. **Write storage integration tests** (table-driven):
   - All repository methods
   - Edge cases and error conditions
 8. **Update CLAUDE.md** with testing instructions
 ## Files to Modify
 - `backend/go.mod` - add test dependencies
 - `backend/internal/api/router.go` - extract interfaces for testability
 - `backend/CLAUDE.md` - add testing instructions
 ## Files to Create
 - `plans/testing-plan.md` - this plan document
 - `backend/internal/api/interfaces.go` - repository interfaces
 - `backend/internal/api/mocks_test.go` - mock implementations
 - `backend/internal/api/exercises_test.go`
 - `backend/internal/api/plans_test.go`
 - `backend/internal/api/sessions_test.go`
 - `backend/internal/storage/testhelpers_test.go`
 - `backend/internal/storage/exercises_test.go`
 - `backend/internal/storage/plans_test.go`
 - `backend/internal/storage/sessions_test.go`
 ## Verification
 ```bash
 cd backend
 # Run all tests
 go test ./...
 # Run with verbose output
 go test -v ./...
 # Run with coverage
 go test -cover ./...
 # Run only unit tests (fast)
 go test -short ./...
 # Run specific package
 go test -v ./internal/api/...
 ```
--- a/project.md
+++ b/project.md
@@ -0,0 +1,13 @@
 # Training tracker
 Will be application for tracking my activities relevant to training.
 It will have:
 - frontend: 
    - mobile friendly web application which is gonna let me view training plan for the session, will allow to enter session type, weights/resistance, repetitions, duration or other relevant attributes of the session.
    - technologies to be used: html, css, javascript
 - backend:
    - service written in golang available over http/https allowing frontend to access/persist all the necessary information
    - persistent layer will ba suitable database, either sql or nosql
 - auxiliary services:
    - this is something extra which does not have to be part of 1st version of the app and will be able to read data from strava or whoop