feat: implement multi-stage Dockerfile for deployment infrastructure

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile

@@ -0,0 +1,38 @@
+# Builder stage
+FROM golang:1.26-alpine AS builder
+
+WORKDIR /app
+
+# Copy go.mod and go.sum
+COPY go.mod go.sum ./
+
+# Download dependencies
+RUN go mod download
+
+# Copy source code
+COPY . .
+
+# Build api and cron binaries
+RUN go build -o api ./cmd/api
+RUN go build -o cron ./cmd/cron
+
+# Runtime stage
+FROM alpine:latest
+
+WORKDIR /app
+
+# Copy binaries from builder
+COPY --from=builder /app/api /app/api
+COPY --from=builder /app/cron /app/cron
+
+# Set environment variables
+ENV DB_DSN="postgres://postgres:postgres@postgres:5432/trip_planner?sslmode=disable"
+ENV REDIS_ADDR="redis:6379"
+ENV YANDEX_API_KEY=""
+ENV TRIP_PLANNER_ADMIN_API_KEY=""
+
+# Expose port
+EXPOSE 8080
+
+# Set entrypoint for api service (default)
+ENTRYPOINT ["/app/api"]

cmd/cron/main.go

@@ -0,0 +1,68 @@
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/go-redis/redis/v8"
+
+	"trip-planner/internal/cache"
+	"trip-planner/internal/metrics"
+	"trip-planner/internal/yandex"
+)
+
+func main() {
+	redisClient := initRedis()
+	m := metrics.New()
+
+	apiKey := os.Getenv("YANDEX_API_KEY")
+	if apiKey == "" {
+		log.Fatal("YANDEX_API_KEY environment variable is not set")
+	}
+	yandexClient := yandex.NewClient(apiKey, yandex.WithMetrics(m))
+
+	// Define monitored stations
+	monitoredStations := []string{
+		// Add station IDs here
+	}
+
+	monitors := make([]*StationMonitor, 0, len(monitoredStations))
+	for _, stationID := range monitoredStations {
+		monitors = append(monitors, &StationMonitor{
+			ID:     stationID,
+			Yandex: yandexClient,
+			Cache:  cache.NewCacheStore(redisClient, m),
+		})
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Set up signal handling for graceful shutdown
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+
+	log.Println("Cron service starting, checking station statuses...")
+
+	// Run the station status check
+	if err := ProcessAllStations(ctx, monitors); err != nil {
+		log.Printf("ERROR: failed to process stations: %v", err)
+	}
+
+	// Wait for signal to exit
+	<-sigChan
+	log.Println("Cron service shutting down...")
+}
+
+// initRedis initializes a Redis client connection.
+func initRedis() *redis.Client {
+	rdb := redis.NewClient(&redis.Options{
+		Addr:     os.Getenv("REDIS_ADDR"),
+		Password: "",
+		DB:       0,
+	})
+	return rdb
+}

cmd/cron/station_status.go

@@ -1,4 +1,4 @@
-package cron
+package main
 
 import (
 	"context"

cmd/cron/station_status_test.go

@@ -1,4 +1,4 @@
-package cron
+package main
 
 import (
 	"context"

docs/plans/2026-08-18-implement-deployment-infrastructure.md

@@ -0,0 +1,116 @@
+# 2026-08-18-implement-deployment-infrastructure
+
+## Overview
+
+- Clear description of the feature/change being implemented: Implement the complete deployment infrastructure for the trip-planner service including Dockerfile, updated docker-compose.yml with cron and watchtower services, and Gitea Actions CI/CD workflow.
+- Problem it solves and key benefits: The project has the core routing logic, API endpoints, caching, and frontend fully implemented, but lacks the deployment infrastructure specified in `docs/deployment.md`. This plan adds the missing Dockerfile, completes docker-compose.yml with cron and watchtower services, and creates the Gitea Actions CI/CD workflow for automated build and deployment.
+- How it integrates with existing system: The deployment infrastructure wraps the existing Go backend (API and cron services) in Docker containers and provides automated CI/CD pipeline for building and pushing images to a registry, with watchtower handling automatic updates on the production server.
+
+## Context (from discovery)
+
+- Files/components involved:
+  - `Dockerfile` (to be created)
+  - `docker-compose.yml` (to be updated with cron and watchtower services, redis_data volume)
+  - `.gitea/workflows/deploy.yml` (to be created)
+  - Existing: `/cmd/api/main.go`, `/cmd/cron/station_status.go`, `go.mod`, `go.sum`
+- Related patterns found: Multi-stage Docker build for Go applications, Gitea Actions workflow with checkout, setup Go, lint & test, build binaries, Docker build & push, watchtower for CD.
+- Dependencies identified: Go 1.22+, PostgreSQL 15-alpine, Redis 7-alpine, nickfedor/watchtower image.
+
+## Development Approach
+
+- **Testing approach**: TDD (tests first) - Define test scenarios and verify deployment files work correctly
+- Complete each task fully before moving to the next
+- Make small, focused changes
+- **CRITICAL: every task MUST include verification** for deployment files
+  - verification is not optional - they are a required part of the checklist
+  - verify Dockerfile syntax and multi-stage structure
+  - verify docker-compose.yml syntax and service definitions
+  - verify Gitea Actions workflow YAML syntax
+  - include both success and error scenarios in verification
+- **CRITICAL: all verifications must pass before starting next task** - no exceptions
+- **CRITICAL: update this plan file when scope changes during implementation**
+- Keep plan in sync with actual work done
+
+## Testing Strategy
+
+- **Verification tests**: required for every task (see Development Approach above)
+- **Syntax validation**: verify YAML files with yaml lint, verify Dockerfile with docker build --dry-run
+- **Configuration validation**: verify docker-compose.yml with `docker-compose config`, verify Gitea Actions workflow syntax
+
+## Progress Tracking
+
+- Mark completed items with `[x]` immediately when done
+- Add newly discovered tasks with ➕ prefix
+- Document issues/blockers with ⚠️ prefix
+- Update plan if implementation deviates from original scope
+- Keep plan in sync with actual work done
+
+## What Goes Where
+
+- **Implementation Steps** (`[ ]` checkboxes): tasks achievable within this codebase - creating Dockerfile, updating docker-compose.yml, creating Gitea Actions workflow
+- **Post-Completion** (no checkboxes): items requiring external action - manual testing on production server, registry configuration, third-party service integrations to verify
+- **Checkbox placement**: Checkboxes belong only in Task sections (`### Task N:`). Do not put checkboxes in Success criteria, Overview, or Context — they cause extra loop iterations.
+
+## Implementation Steps
+
+### Task 1: Create Multi-stage Dockerfile
+- [x] create Dockerfile with builder stage (Go 1.26+, build api and cron binaries)
+- [x] create Dockerfile with runtime stage (alpine, copy binaries, set entrypoint)
+- [x] verify Dockerfile syntax with `docker build` (successful build)
+- [x] verify multi-stage structure produces minimal runtime image (27.1MB)
+
+### Task 2: Update docker-compose.yml
+- [ ] add `cron` service (Go cron binary, depends_on: postgres, redis)
+- [ ] add `watchtower` service (nickfedor/watchtower image, volume for docker.sock, command for cleanup)
+- [ ] add `redis_data` volume to volumes section
+- [ ] verify docker-compose.yml syntax with `docker-compose config`
+
+### Task 3: Create Gitea Actions CI/CD Workflow
+- [ ] create `.gitea/workflows/deploy.yml` file
+- [ ] add checkout step (actions/checkout@v3)
+- [ ] add setup Go step (actions/setup-go@v4, go-version: '1.22')
+- [ ] add Go modules cache step (actions/cache@v3)
+- [ ] add lint & test step (golangci-lint, go test -v -race ./...)
+- [ ] add Docker Buildx setup step (docker/setup-buildx-action@v2)
+- [ ] add Docker login step (docker/login-action@v2)
+- [ ] add Docker build & push step (docker/build-push-action@v4, tags: latest and {{.CommitID}})
+- [ ] verify Gitea Actions workflow YAML syntax
+
+### Task 4: Verify acceptance criteria
+- [ ] verify Dockerfile matches multi-stage specification
+- [ ] verify docker-compose.yml has api, cron, postgres, redis, watchtower services
+- [ ] verify Gitea Actions workflow has all required steps (checkout, setup Go, lint & test, build binaries, Docker build & push)
+- [ ] verify all YAML files are valid syntax
+- [ ] verify docker-compose.yml volumes section includes pg_data and redis_data
+
+## Technical Details
+
+- **Dockerfile structure**:
+  - Builder stage: `golang:1.22-alpine` as builder, copy go.mod/go.sum, `go mod download`, copy source, `go build -o api cmd/api/main.go`, `go build -o cron cmd/cron/main.go`
+  - Runtime stage: `alpine:latest` or `scratch`, copy binaries from builder, set environment variables, expose port 8080, set entrypoint
+
+- **docker-compose.yml services**:
+  - `api`: build from Dockerfile, ports: 8080:8080, environment: DB_DSN, REDIS_ADDR, YANDEX_API_KEY, depends_on: db, redis
+  - `cron`: build from Dockerfile, environment: same as api, depends_on: db, redis
+  - `db` (postgres): postgres:15-alpine, environment: POSTGRES_USER, POSTGRES_PASSWORD, POSTGRES_DB, volumes: pg_data
+  - `redis`: redis:7-alpine, volumes: redis_data
+  - `watchtower`: nickfedor/watchtower, volumes: /var/run/docker.sock:/var/run/docker.sock, command: --interval 60 --cleanup travel-api
+
+- **.gitea/workflows/deploy.yml structure**:
+  - on: push to master branch
+  - jobs: build-and-deploy on ubuntu-latest
+  - steps: Checkout Code, Set up Go, Go Modules Cache, Run Tests, Set up Docker Buildx, Login to Docker Registry, Build and Push Docker Image
+
+## Post-Completion
+
+*Items requiring manual intervention or external systems - no checkboxes, informational only*
+
+**Manual verification** (if applicable):
+- Test docker-compose.yml on local Docker environment
+- Test Gitea Actions workflow in a test repository
+- Verify watchtower auto-update behavior on production server
+
+**External system updates** (if applicable):
+- Configure Docker Registry credentials in Gitea Secrets (DOCKER_USERNAME, DOCKER_PASSWORD)
+- Configure YANDEX_API_KEY and TRIP_PLANNER_ADMIN_API_KEY in Docker Compose .env file
+- Verify PostgreSQL and Redis persistence volumes are properly mounted