Containerization for Testing: Complete Guide to Docker, Kubernetes & Testcontainers

# Multi-stage build for optimal image size
FROM node:18-alpine AS builder

# Install build dependencies
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production

# Runtime stage
FROM node:18-alpine

# Install testing tools
RUN apk add --no-cache \
    curl \
    wget \
    chromium \
    chromium-chromedriver

# Set up non-root user for security
RUN addgroup -g 1001 tester && \
    adduser -D -u 1001 -G tester tester

WORKDIR /app
COPY --from=builder /app/node_modules ./node_modules
COPY . .

# Change ownership
RUN chown -R tester:tester /app

USER tester

# Environment variables for testing
ENV NODE_ENV=test
ENV CHROME_BIN=/usr/bin/chromium-browser
ENV CHROME_PATH=/usr/lib/chromium/

# Health check
HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
    CMD node healthcheck.js || exit 1

CMD ["npm", "test"]

FROM python:3.11-slim

# Install system dependencies
RUN apt-get update && apt-get install -y \
    gcc \
    postgresql-client \
    curl \
    && rm -rf /var/lib/apt/lists/*

# Set up working directory
WORKDIR /tests

# Install Python dependencies
COPY requirements.txt requirements-test.txt ./
RUN pip install --no-cache-dir -r requirements.txt -r requirements-test.txt

# Copy test code
COPY tests/ ./tests/
COPY conftest.py pytest.ini ./

# Create test results directory
RUN mkdir -p /tests/results && \
    chmod 777 /tests/results

# Run tests with pytest
CMD (as discussed in [IDE and Extensions for Testers: Complete Tooling Guide for QA Engineers](/blog/ide-extensions-for-testers)) ["pytest", "-v", "--junitxml=/tests/results/junit.xml", \
     "--html=/tests/results/report.html", "--self-contained-html"]

version: '3.8'

services:
  # Application under test
  app:
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - "3000:3000"
    environment:
      - DATABASE_URL=postgresql://testuser:testpass@postgres:5432/testdb
      - REDIS_URL=redis://redis:6379
      - NODE_ENV=test
    depends_on:
      postgres:
        condition: service_healthy
      redis:
        condition: service_started
    networks:
      - test-network
    volumes:
      - ./coverage:/app/coverage

  # PostgreSQL database
  postgres:
    image: postgres:15-alpine
    environment:
      POSTGRES_USER: testuser
      POSTGRES_PASSWORD: testpass
      POSTGRES_DB: testdb
    ports:
      - "5432:5432"
    volumes:
      - postgres-data:/var/lib/postgresql/data
      - ./init-scripts:/docker-entrypoint-initdb.d
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U testuser -d testdb"]
      interval: 10s
      timeout: 5s
      retries: 5
    networks:
      - test-network

  # Redis cache
  redis:
    image: redis:7-alpine
    ports:
      - "6379:6379"
    networks:
      - test-network
    healthcheck:
      test: ["CMD", "redis-cli", "ping"]
      interval: 10s
      timeout: 3s
      retries: 5

  # Selenium Grid Hub
  selenium-hub:
    image: selenium/hub:4.15.0
    ports:
      - "4444:4444"
      - "4442:4442"
      - "4443:4443"
    environment:
      - SE_SESSION_REQUEST_TIMEOUT=300
      - SE_SESSION_RETRY_INTERVAL=5
      - SE_NODE_MAX_SESSIONS=5
    networks:
      - test-network

  # Chrome node
  chrome:
    image: selenium/node-chrome:4.15.0
    shm_size: 2gb
    depends_on:
      - selenium-hub
    environment:
      - SE_EVENT_BUS_HOST=selenium-hub
      - SE_EVENT_BUS_PUBLISH_PORT=4442
      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
      - SE_NODE_MAX_SESSIONS=5
      - SE_NODE_SESSION_TIMEOUT=300
    networks:
      - test-network

  # Firefox node
  firefox:
    image: selenium/node-firefox:4.15.0
    shm_size: 2gb
    depends_on:
      - selenium-hub
    environment:
      - SE_EVENT_BUS_HOST=selenium-hub
      - SE_EVENT_BUS_PUBLISH_PORT=4442
      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
      - SE_NODE_MAX_SESSIONS=5
    networks:
      - test-network

  # Integration test runner
  tests:
    build:
      context: .
      dockerfile: Dockerfile.test
    depends_on:
      app:
        condition: service_started
      selenium-hub:
        condition: service_started
    environment:
      - APP_URL=http://app:3000
      - SELENIUM_URL=http://selenium-hub:4444/wd/hub
      - DATABASE_URL=postgresql://testuser:testpass@postgres:5432/testdb
    volumes:
      - ./tests:/tests
      - ./test-results:/test-results
    networks:
      - test-network
    command: ["./wait-for-it.sh", "app:3000", "--", "pytest", "-v"]

networks:
  test-network:
    driver: bridge

volumes:
  postgres-data:

# Using healthchecks with depends_on
services:
  app:
    depends_on:
      database:
        condition: service_healthy
      cache:
        condition: service_started
    # App will only start after database is healthy

  database:
    healthcheck:
      test: ["CMD", "mysqladmin", "ping", "-h", "localhost"]
      timeout: 20s
      retries: 10

#!/bin/bash
# wait-for-it.sh - Wait for service availability

set -e

host="$1"
shift
port="$1"
shift
cmd="$@"

until nc -z "$host" "$port"; do
  >&2 echo "Service $host:$port is unavailable - sleeping"
  sleep 1
done

>&2 echo "Service $host:$port is up - executing command"
exec $cmd

networks:
  frontend:
    driver: bridge
    ipam:
      config:
        - subnet: 172.20.0.0/16
  
  backend:
    driver: bridge
    internal: true  # No external access

services:
  web:
    networks:
      - frontend
      - backend
  
  database:
    networks:
      - backend  # Only accessible from backend network

services:
  test-runner:
    image: test-runner:latest
    deploy:
      resources:
        limits:
          cpus: '2.0'
          memory: 2G
        reservations:
          cpus: '1.0'
          memory: 1G
    ulimits:
      nofile:
        soft: 65536
        hard: 65536

apiVersion: v1
kind: Pod
metadata:
  name: test-runner
  labels:
    app: test-runner
    type: integration-test
spec:
  restartPolicy: Never
  containers:
  - name: test-runner
    image: myregistry/test-runner:latest
    command: ["pytest", "-v", "--junitxml=/results/junit.xml"]
    resources:
      requests:
        memory: "1Gi"
        cpu: "500m"
      limits:
        memory: "2Gi"
        cpu: "1000m"
    volumeMounts:
    - name: test-results
      mountPath: /results
    env:
    - name: DATABASE_URL
      valueFrom:
        secretKeyRef:
          name: test-secrets
          key: database-url
    - name: TEST_ENVIRONMENT
      value: "kubernetes"
  volumes:
  - name: test-results
    persistentVolumeClaim:
      claimName: test-results-pvc

apiVersion: batch/v1
kind: Job
metadata:
  name: integration-tests
  namespace: testing
spec:
  # Run tests with 5 parallel pods
  parallelism: 5
  completions: 5
  backoffLimit: 2
  ttlSecondsAfterFinished: 3600  # Clean up after 1 hour
  
  template:
    metadata:
      labels:
        job: integration-tests
    spec:
      restartPolicy: Never
      containers:
      - name: test-runner
        image: myregistry/integration-tests:v1.2.3
        command:
        - /bin/sh
        - -c
        - |
          echo "Starting test execution on pod ${HOSTNAME}"
          pytest tests/ \
            --junitxml=/results/junit-${HOSTNAME}.xml \
            --html=/results/report-${HOSTNAME}.html \
            -n auto
        resources:
          requests:
            memory: "2Gi"
            cpu: "1000m"
          limits:
            memory: "4Gi"
            cpu: "2000m"
        volumeMounts:
        - name: shared-results
          mountPath: /results
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: API_ENDPOINT
          valueFrom:
            configMapKeyRef:
              name: test-config
              key: api-endpoint
      volumes:
      - name: shared-results
        persistentVolumeClaim:
          claimName: test-results-pvc

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-environment
  namespace: testing
spec:
  replicas: 3
  selector:
    matchLabels:
      app: test-app
  template:
    metadata:
      labels:
        app: test-app
        version: v1
    spec:
      containers:
      - name: app
        image: myapp:test
        ports:
        - containerPort: 8080
        env:
        - name: DATABASE_HOST
          value: postgres-service
        - name: REDIS_HOST
          value: redis-service
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 30
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /ready
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 5
---
apiVersion: v1
kind: Service
metadata:
  name: test-app-service
  namespace: testing
spec:
  selector:
    app: test-app
  ports:
  - protocol: TCP
    port: 80
    targetPort: 8080
  type: ClusterIP

apiVersion: v1
kind: ConfigMap
metadata:
  name: test-config
  namespace: testing
data:
  api-endpoint: "http://test-app-service"
  test-timeout: "300"
  parallel-workers: "10"
  pytest.ini: |
    [pytest]
    testpaths = tests
    python_files = test_*.py
    python_functions = test_*
    markers =
        smoke: Quick smoke tests
        integration: Integration tests
        slow: Slow running tests

---
apiVersion: v1
kind: Secret
metadata:
  name: test-secrets
  namespace: testing
type: Opaque
stringData:
  database-url: "postgresql://user:password@postgres:5432/testdb"
  api-key: "test-api-key-12345"
  auth-token: "Bearer test-token-xyz"

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: test-runner-hpa
  namespace: testing
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: test-environment
  minReplicas: 2
  maxReplicas: 20
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70
  - type: Resource
    resource:
      name: memory
      target:
        type: Utilization
        averageUtilization: 80
  behavior:
    scaleUp:
      stabilizationWindowSeconds: 60
      policies:
      - type: Percent
        value: 100
        periodSeconds: 60
    scaleDown:
      stabilizationWindowSeconds: 300
      policies:
      - type: Percent
        value: 50
        periodSeconds: 60

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: test-results-pvc
  namespace: testing
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 10Gi
  storageClassName: standard

---
apiVersion: v1
kind: Pod
metadata:
  name: artifact-collector
  namespace: testing
spec:
  containers:
  - name: collector
    image: nginx:alpine
    ports:
    - containerPort: 80
    volumeMounts:
    - name: test-results
      mountPath: /usr/share/nginx/html
      readOnly: true
  volumes:
  - name: test-results
    persistentVolumeClaim:
      claimName: test-results-pvc

import org.junit.jupiter.api.Test;
import org.testcontainers.containers.PostgreSQLContainer;
import org.testcontainers.junit.jupiter.Container;
import org.testcontainers.junit.jupiter.Testcontainers;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

@Testcontainers
public class DatabaseIntegrationTest {
    
    @Container
    private static final PostgreSQLContainer<?> postgres = 
        new PostgreSQLContainer<>("postgres:15-alpine")
            .withDatabaseName("testdb")
            .withUsername("testuser")
            .withPassword("testpass")
            .withInitScript("init.sql");
    
    @Test
    void testDatabaseConnection() throws Exception {
        String jdbcUrl = postgres.getJdbcUrl();
        
        try (Connection conn = DriverManager.getConnection(
                jdbcUrl, 
                postgres.getUsername(), 
                postgres.getPassword());
             Statement stmt = conn.createStatement()) {
            
            ResultSet rs = stmt.executeQuery("SELECT version()");
            rs.next();
            String version = rs.getString(1);
            
            assertNotNull(version);
            assertTrue(version.contains("PostgreSQL"));
        }
    }
    
    @Test
    void testUserRepository() {
        UserRepository repository = new UserRepository(postgres.getJdbcUrl());
        
        User user = new User("john@example.com", "John Doe");
        repository.save(user);
        
        Optional<User> found = repository.findByEmail("john@example.com");
        assertTrue(found.isPresent());
        assertEquals("John Doe", found.get().getName());
    }
}

import org.testcontainers.containers.GenericContainer;
import org.testcontainers.containers.Network;
import org.testcontainers.containers.wait.strategy.Wait;
import org.testcontainers.utility.DockerImageName;

public class MicroserviceIntegrationTest {
    
    private static final Network network = Network.newNetwork();
    
    @Container
    private static final PostgreSQLContainer<?> database = 
        new PostgreSQLContainer<>("postgres:15")
            .withNetwork(network)
            .withNetworkAliases("database");
    
    @Container
    private static final GenericContainer<?> redis = 
        new GenericContainer<>(DockerImageName.parse("redis:7-alpine"))
            .withNetwork(network)
            .withNetworkAliases("redis")
            .withExposedPorts(6379);
    
    @Container
    private static final GenericContainer<?> app = 
        new GenericContainer<>(DockerImageName.parse("myapp:latest"))
            .withNetwork(network)
            .withExposedPorts(8080)
            .withEnv("DATABASE_URL", "jdbc:postgresql://database:5432/testdb")
            .withEnv("REDIS_URL", "redis://redis:6379")
            .dependsOn(database, redis)
            .waitingFor(Wait.forHttp("/health").forStatusCode(200));
    
    @Test
    void testFullStack() {
        String baseUrl = String.format("http://%s:%d", 
            app.getHost(), 
            app.getMappedPort(8080));
        
        // Make HTTP requests to the application
        RestAssured.baseURI = baseUrl;
        
        given()
            .contentType("application/json")
            .body(new CreateUserRequest("test@example.com"))
        .when()
            .post("/api/users")
        .then()
            .statusCode(201)
            .body("email", equalTo("test@example.com"));
    }
}

import org.testcontainers.containers.ComposeContainer;
import org.testcontainers.containers.wait.strategy.Wait;
import java.io.File;
import java.time.Duration;

public class ComposeIntegrationTest {
    
    @Container
    private static final ComposeContainer environment = 
        new ComposeContainer(new File("docker-compose.test.yml"))
            .withExposedService("app", 8080, 
                Wait.forHttp("/health")
                    .forStatusCode(200)
                    .withStartupTimeout(Duration.ofMinutes(2)))
            .withExposedService("postgres", 5432,
                Wait.forListeningPort())
            .withLocalCompose(true)
            .withPull(false);
    
    @Test
    void testCompleteSystem() {
        String appHost = environment.getServiceHost("app", 8080);
        Integer appPort = environment.getServicePort("app", 8080);
        
        String baseUrl = String.format("http://%s:%d", appHost, appPort);
        
        // Run integration tests against the full environment
        Response response = RestAssured.get(baseUrl + "/api/status");
        assertEquals(200, response.getStatusCode());
    }
}

import pytest
from testcontainers.postgres import PostgresContainer
import psycopg2

@pytest.fixture(scope="module")
def postgres_container():
    with PostgresContainer("postgres:15-alpine") as postgres:
        yield postgres

def test_database_operations(postgres_container):
    # Get connection parameters
    connection_url = postgres_container.get_connection_url()
    
    # Connect to database
    conn = psycopg2.connect(connection_url)
    cursor = conn.cursor()
    
    # Create table
    cursor.execute("""
        CREATE TABLE users (
            id SERIAL PRIMARY KEY,
            email VARCHAR(255) UNIQUE NOT NULL,
            name VARCHAR(255) NOT NULL
        )
    """)
    
    # Insert data
    cursor.execute(
        "INSERT INTO users (email, name) VALUES (%s, %s)",
        ("test@example.com", "Test User")
    )
    conn.commit()
    
    # Query data
    cursor.execute("SELECT * FROM users WHERE email = %s", ("test@example.com",))
    result = cursor.fetchone()
    
    assert result is not None
    assert result[1] == "test@example.com"
    assert result[2] == "Test User"
    
    cursor.close()
    conn.close()

def test_sqlalchemy_integration(postgres_container):
    from sqlalchemy import create_engine, Column, Integer, String
    from sqlalchemy.ext.declarative import declarative_base
    from sqlalchemy.orm import sessionmaker
    
    Base = declarative_base()
    
    class User(Base):
        __tablename__ = 'users'
        id = Column(Integer, primary_key=True)
        email = Column(String, unique=True)
        name = Column(String)
    
    # Create engine
    engine = create_engine(postgres_container.get_connection_url())
    Base.metadata.create_all(engine)
    
    # Create session
    Session = sessionmaker(bind=engine)
    session = Session()
    
    # Add user
    user = User(email="sqlalchemy@example.com", name="SQLAlchemy User")
    session.add(user)
    session.commit()
    
    # Query user
    found = session.query(User).filter_by(email="sqlalchemy@example.com").first()
    assert found is not None
    assert found.name == "SQLAlchemy User"

from testcontainers.redis import RedisContainer
import redis

@pytest.fixture(scope="module")
def redis_container():
    with RedisContainer("redis:7-alpine") as redis_cont:
        yield redis_cont

def test_redis_operations(redis_container):
    # Get connection details
    host = redis_container.get_container_host_ip()
    port = redis_container.get_exposed_port(6379)
    
    # Connect to Redis
    client = redis.Redis(host=host, port=port, decode_responses=True)
    
    # Set and get value
    client.set("test_key", "test_value")
    value = client.get("test_key")
    
    assert value == "test_value"
    
    # Test expiration
    client.setex("temp_key", 1, "temporary")
    assert client.get("temp_key") == "temporary"
    
    import time
    time.sleep(2)
    assert client.get("temp_key") is None

from testcontainers.core.container import DockerContainer
from testcontainers.core.waiting_strategies import wait_for_logs
import requests

@pytest.fixture(scope="module")
def custom_app_container():
    container = (
        DockerContainer("myapp:test")
        .with_exposed_ports(8080)
        .with_env("DATABASE_URL", "sqlite:///test.db")
        .with_env("LOG_LEVEL", "DEBUG")
        .with_volume_mapping("/tmp/test-data", "/app/data")
    )
    
    with container:
        # Wait for application to be ready
        wait_for_logs(container, "Application started", timeout=30)
        yield container

def test_application_endpoint(custom_app_container):
    host = custom_app_container.get_container_host_ip()
    port = custom_app_container.get_exposed_port(8080)
    
    url = f"http://{host}:{port}/api/health"
    response = requests.get(url)
    
    assert response.status_code == 200
    assert response.json()["status"] == "healthy"

const { MongoDBContainer } = require('@testcontainers/mongodb');
const { MongoClient } = require('mongodb');

describe('MongoDB Integration Tests', () => {
    let container;
    let client;
    let db;

    beforeAll(async () => {
        // Start MongoDB container
        container = await new MongoDBContainer('mongo:7')
            .withExposedPorts(27017)
            .start();

        // Connect to MongoDB
        const connectionString = container.getConnectionString();
        client = await MongoClient.connect(connectionString);
        db = client.db('testdb');
    }, 60000);

    afterAll(async () => {
        await client?.close();
        await container?.stop();
    });

    test('should insert and find documents', async () => {
        const collection = db.collection('users');

        // Insert document
        const result = await collection.insertOne({
            email: 'test@example.com',
            name: 'Test User',
            createdAt: new Date()
        });

        expect(result.acknowledged).toBe(true);

        // Find document
        const user = await collection.findOne({ email: 'test@example.com' });
        
        expect(user).toBeDefined();
        expect(user.name).toBe('Test User');
    });

    test('should update documents', async () => {
        const collection = db.collection('users');

        await collection.updateOne(
            { email: 'test@example.com' },
            { $set: { name: 'Updated User' } }
        );

        const user = await collection.findOne({ email: 'test@example.com' });
        expect(user.name).toBe('Updated User');
    });
});

const { PostgreSqlContainer } = require('@testcontainers/postgresql');
const { Client } = require('pg');

describe('PostgreSQL Advanced Tests', () => {
    let container;
    let client;

    beforeAll(async () => {
        container = await new PostgreSqlContainer('postgres:15-alpine')
            .withDatabase('testdb')
            .withUsername('testuser')
            .withPassword('testpass')
            .withCopyFilesToContainer([{
                source: './init.sql',
                target: '/docker-entrypoint-initdb.d/init.sql'
            }])
            .withEnvironment({
                'POSTGRES_INITDB_ARGS': '--encoding=UTF8 --locale=en_US.UTF-8'
            })
            .withTmpFs({ '/var/lib/postgresql/data': 'rw,noexec,nosuid,size=1024m' })
            .start();

        client = new Client({
            host: container.getHost(),
            port: container.getMappedPort(5432),
            database: container.getDatabase(),
            user: container.getUsername(),
            password: container.getPassword()
        });

        await client.connect();
    }, 60000);

    afterAll(async () => {
        await client?.end();
        await container?.stop();
    });

    test('should execute complex queries', async () => {
        const result = await client.query(`
            SELECT 
                u.id, 
                u.name, 
                COUNT(o.id) as order_count
            FROM users u
            LEFT JOIN orders o ON u.id = o.user_id
            GROUP BY u.id, u.name
            HAVING COUNT(o.id) > 0
        `);

        expect(result.rows).toEqual(expect.arrayContaining([
            expect.objectContaining({
                id: expect.any(Number),
                name: expect.any(String),
                order_count: expect.any(String)
            })
        ]));
    });
});

const { GenericContainer, Network } = require('testcontainers');
const axios = require('axios');

describe('Microservices Integration', () => {
    let network;
    let dbContainer;
    let redisContainer;
    let appContainer;
    let baseUrl;

    beforeAll(async () => {
        // Create shared network
        network = await new Network().start();

        // Start PostgreSQL
        dbContainer = await new GenericContainer('postgres:15-alpine')
            .withNetwork(network)
            .withNetworkAliases('database')
            .withEnvironment({
                POSTGRES_DB: 'appdb',
                POSTGRES_USER: 'appuser',
                POSTGRES_PASSWORD: 'apppass'
            })
            .withExposedPorts(5432)
            .start();

        // Start Redis
        redisContainer = await new GenericContainer('redis:7-alpine')
            .withNetwork(network)
            .withNetworkAliases('redis')
            .withExposedPorts(6379)
            .start();

        // Start application
        appContainer = await new GenericContainer('myapp:latest')
            .withNetwork(network)
            .withEnvironment({
                DATABASE_URL: 'postgresql://appuser:apppass@database:5432/appdb',
                REDIS_URL: 'redis://redis:6379'
            })
            .withExposedPorts(3000)
            .withWaitStrategy(Wait.forHttp('/health', 3000))
            .start();

        const host = appContainer.getHost();
        const port = appContainer.getMappedPort(3000);
        baseUrl = `http://${host}:${port}`;
    }, 120000);

    afterAll(async () => {
        await appContainer?.stop();
        await redisContainer?.stop();
        await dbContainer?.stop();
        await network?.stop();
    });

    test('should create and retrieve user', async () => {
        // Create user
        const createResponse = await axios.post(`${baseUrl}/api/users`, {
            email: 'integration@example.com',
            name: 'Integration Test User'
        });

        expect(createResponse.status).toBe(201);
        const userId = createResponse.data.id;

        // Retrieve user
        const getResponse = await axios.get(`${baseUrl}/api/users/${userId}`);
        
        expect(getResponse.status).toBe(200);
        expect(getResponse.data.email).toBe('integration@example.com');
    });

    test('should cache frequently accessed data', async () => {
        const userId = 1;
        
        // First request (cache miss)
        const start1 = Date.now();
        await axios.get(`${baseUrl}/api/users/${userId}`);
        const duration1 = Date.now() - start1;

        // Second request (cache hit)
        const start2 = Date.now();
        await axios.get(`${baseUrl}/api/users/${userId}`);
        const duration2 = Date.now() - start2;

        // Second request should be faster (cached)
        expect(duration2).toBeLessThan(duration1);
    });
});

version: '3.8'

x-common-variables: &common-variables
  NODE_ENV: test
  LOG_LEVEL: debug
  
services:
  # Test database with initialization
  test-db:
    image: postgres:15-alpine
    environment:
      POSTGRES_DB: testdb
      POSTGRES_USER: testuser
      POSTGRES_PASSWORD: testpass
      PGDATA: /var/lib/postgresql/data/pgdata
    volumes:
      - ./db-init:/docker-entrypoint-initdb.d
      - postgres-data:/var/lib/postgresql/data
    ports:
      - "5432:5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U testuser"]
      interval: 5s
      timeout: 5s
      retries: 10
    networks:
      - test-net

  # Redis for caching and sessions
  test-redis:
    image: redis:7-alpine
    command: redis-server --appendonly yes --requirepass testpass
    volumes:
      - redis-data:/data
    ports:
      - "6379:6379"
    healthcheck:
      test: ["CMD", "redis-cli", "--raw", "incr", "ping"]
      interval: 5s
      timeout: 3s
      retries: 5
    networks:
      - test-net

  # Message queue
  test-rabbitmq:
    image: rabbitmq:3-management-alpine
    environment:
      RABBITMQ_DEFAULT_USER: testuser
      RABBITMQ_DEFAULT_PASS: testpass
    ports:
      - "5672:5672"
      - "15672:15672"
    healthcheck:
      test: ["CMD", "rabbitmq-diagnostics", "ping"]
      interval: 10s
      timeout: 10s
      retries: 5
    networks:
      - test-net

  # Elasticsearch for search
  test-elasticsearch:
    image: docker.elastic.co/elasticsearch/elasticsearch:8.11.0
    environment:
      - discovery.type=single-node
      - xpack.security.enabled=false
      - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
    volumes:
      - es-data:/usr/share/elasticsearch/data
    ports:
      - "9200:9200"
    healthcheck:
      test: ["CMD-SHELL", "curl -f http://localhost:9200/_cluster/health || exit 1"]
      interval: 10s
      timeout: 5s
      retries: 10
    networks:
      - test-net

  # API Gateway
  api-gateway:
    build:
      context: ./services/gateway
      dockerfile: Dockerfile.test
    environment:
      <<: *common-variables
      PORT: 8080
      AUTH_SERVICE_URL: http://auth-service:3001
      USER_SERVICE_URL: http://user-service:3002
    ports:
      - "8080:8080"
    depends_on:
      test-redis:
        condition: service_healthy
    networks:
      - test-net
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:8080/health"]
      interval: 10s
      timeout: 5s
      retries: 5

  # Authentication Service
  auth-service:
    build:
      context: ./services/auth
      dockerfile: Dockerfile.test
    environment:
      <<: *common-variables
      PORT: 3001
      DATABASE_URL: postgresql://testuser:testpass@test-db:5432/testdb
      REDIS_URL: redis://:testpass@test-redis:6379
    depends_on:
      test-db:
        condition: service_healthy
      test-redis:
        condition: service_healthy
    networks:
      - test-net
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:3001/health"]
      interval: 10s
      timeout: 5s
      retries: 5

  # User Service
  user-service:
    build:
      context: ./services/users
      dockerfile: Dockerfile.test
    environment:
      <<: *common-variables
      PORT: 3002
      DATABASE_URL: postgresql://testuser:testpass@test-db:5432/testdb
      ELASTICSEARCH_URL: http://test-elasticsearch:9200
      RABBITMQ_URL: amqp://testuser:testpass@test-rabbitmq:5672
    depends_on:
      test-db:
        condition: service_healthy
      test-elasticsearch:
        condition: service_healthy
      test-rabbitmq:
        condition: service_healthy
    networks:
      - test-net
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:3002/health"]
      interval: 10s
      timeout: 5s
      retries: 5

  # E2E Test Runner
  e2e-tests:
    build:
      context: ./tests/e2e
      dockerfile: Dockerfile
    environment:
      API_BASE_URL: http://api-gateway:8080
      SELENIUM_URL: http://selenium-hub:4444/wd/hub
      TEST_USER_EMAIL: test@example.com
      TEST_USER_PASSWORD: testpass123
    volumes:
      - ./tests/e2e:/tests
      - test-results:/test-results
      - ./tests/e2e/screenshots:/screenshots
    depends_on:
      api-gateway:
        condition: service_healthy
      auth-service:
        condition: service_healthy
      user-service:
        condition: service_healthy
      selenium-hub:
        condition: service_started
    networks:
      - test-net
    command: >
      sh -c "
        echo 'Waiting for services to be ready...' &&
        sleep 10 &&
        npm run test:e2e -- --reporter=html --reporter-options output=/test-results/report.html
      "

  # Selenium Grid Hub
  selenium-hub:
    image: selenium/hub:4.15.0
    ports:
      - "4444:4444"
      - "4442:4442"
      - "4443:4443"
    environment:
      GRID_MAX_SESSION: 10
      GRID_BROWSER_TIMEOUT: 300
      GRID_TIMEOUT: 300
    networks:
      - test-net

  # Chrome Nodes
  selenium-chrome:
    image: selenium/node-chrome:4.15.0
    shm_size: 2gb
    depends_on:
      - selenium-hub
    environment:
      SE_EVENT_BUS_HOST: selenium-hub
      SE_EVENT_BUS_PUBLISH_PORT: 4442
      SE_EVENT_BUS_SUBSCRIBE_PORT: 4443
      SE_NODE_MAX_SESSIONS: 5
      SE_SCREEN_WIDTH: 1920
      SE_SCREEN_HEIGHT: 1080
    volumes:
      - /dev/shm:/dev/shm
    networks:
      - test-net

  # Performance monitoring
  test-prometheus:
    image: prom/prometheus:latest
    volumes:
      - ./monitoring/prometheus.yml:/etc/prometheus/prometheus.yml
      - prometheus-data:/prometheus
    command:
      - '--config.file=/etc/prometheus/prometheus.yml'
      - '--storage.tsdb.path=/prometheus'
    ports:
      - "9090:9090"
    networks:
      - test-net

  # Metrics visualization
  test-grafana:
    image: grafana/grafana:latest
    environment:
      GF_SECURITY_ADMIN_PASSWORD: admin
      GF_USERS_ALLOW_SIGN_UP: false
    volumes:
      - grafana-data:/var/lib/grafana
      - ./monitoring/grafana/dashboards:/etc/grafana/provisioning/dashboards
    ports:
      - "3000:3000"
    depends_on:
      - test-prometheus
    networks:
      - test-net

networks:
  test-net:
    driver: bridge

volumes:
  postgres-data:
  redis-data:
  es-data:
  test-results:
  prometheus-data:
  grafana-data:

#!/bin/bash
# healthcheck.sh - Comprehensive service health verification

set -e

check_postgres() {
    pg_isready -h test-db -U testuser -d testdb
}

check_redis() {
    redis-cli -h test-redis -a testpass ping
}

check_api() {
    curl -f http://api-gateway:8080/health || exit 1
}

check_elasticsearch() {
    curl -f http://test-elasticsearch:9200/_cluster/health?wait_for_status=yellow&timeout=30s
}

echo "Checking PostgreSQL..."
until check_postgres; do
    echo "PostgreSQL not ready - sleeping"
    sleep 2
done

echo "Checking Redis..."
until check_redis; do
    echo "Redis not ready - sleeping"
    sleep 2
done

echo "Checking Elasticsearch..."
until check_elasticsearch; do
    echo "Elasticsearch not ready - sleeping"
    sleep 2
done

echo "Checking API Gateway..."
until check_api; do
    echo "API not ready - sleeping"
    sleep 2
done

echo "All services are healthy!"

name: Integration Tests

on:
  push:
    branches: [ main, develop ]
  pull_request:
    branches: [ main ]

jobs:
  integration-tests:
    runs-on: ubuntu-latest
    
    services:
      postgres:
        image: postgres:15-alpine
        env:
          POSTGRES_PASSWORD: testpass
          POSTGRES_USER: testuser
          POSTGRES_DB: testdb
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
        ports:
          - 5432:5432
      
      redis:
        image: redis:7-alpine
        options: >-
          --health-cmd "redis-cli ping"
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
        ports:
          - 6379:6379
    
    steps:
      - uses: actions/checkout@v3
      
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2
      
      - name: Build test image
        uses: docker/build-push-action@v4
        with:
          context: .
          file: ./Dockerfile.test
          push: false
          load: true
          tags: test-runner:latest
          cache-from: type=gha
          cache-to: type=gha,mode=max
      
      - name: Run integration tests
        run: |
          docker run --rm \
            --network host \
            -e DATABASE_URL=postgresql://testuser:testpass@localhost:5432/testdb \
            -e REDIS_URL=redis://localhost:6379 \
            -v ${{ github.workspace }}/test-results:/results \
            test-runner:latest \
            pytest -v --junitxml=/results/junit.xml
      
      - name: Publish test results
        uses: EnricoMi/publish-unit-test-result-action@v2
        if: always()
        with:
          files: test-results/junit.xml
      
      - name: Upload coverage
        uses: codecov/codecov-action@v3
        with:
          files: ./test-results/coverage.xml

  docker-compose-tests:
    runs-on: ubuntu-latest
    
    steps:
      - uses: actions/checkout@v3
      
      - name: Run Docker Compose tests
        run: |
          docker-compose -f docker-compose.test.yml up \
            --abort-on-container-exit \
            --exit-code-from tests
      
      - name: Collect logs
        if: failure()
        run: |
          docker-compose -f docker-compose.test.yml logs > docker-logs.txt
      
      - name: Upload logs
        if: failure()
        uses: actions/upload-artifact@v3
        with:
          name: docker-logs
          path: docker-logs.txt
      
      - name: Cleanup
        if: always()
        run: |
          docker-compose -f docker-compose.test.yml down -v

  kubernetes-tests:
    runs-on: ubuntu-latest
    
    steps:
      - uses: actions/checkout@v3
      
      - name: Set up Minikube
        uses: medyagh/setup-minikube@latest
      
      - name: Deploy test environment
        run: |
          kubectl apply -f k8s/test-namespace.yaml
          kubectl apply -f k8s/test-config.yaml
          kubectl apply -f k8s/test-secrets.yaml
          kubectl apply -f k8s/test-deployment.yaml
          kubectl wait --for=condition=ready pod -l app=test-app -n testing --timeout=300s
      
      - name: Run tests
        run: |
          kubectl apply -f k8s/test-job.yaml
          kubectl wait --for=condition=complete job/integration-tests -n testing --timeout=600s
      
      - name: Collect test results
        if: always()
        run: |
          kubectl logs job/integration-tests -n testing > test-output.log
      
      - name: Cleanup
        if: always()
        run: |
          kubectl delete namespace testing

stages:
  - build
  - test
  - cleanup

variables:
  DOCKER_DRIVER: overlay2
  DOCKER_TLS_CERTDIR: "/certs"
  POSTGRES_DB: testdb
  POSTGRES_USER: testuser
  POSTGRES_PASSWORD: testpass

build-test-image:
  stage: build
  image: docker:24
  services:
    - docker:24-dind
  script:
    - docker build -t $CI_REGISTRY_IMAGE/test-runner:$CI_COMMIT_SHA -f Dockerfile.test .
    - docker push $CI_REGISTRY_IMAGE/test-runner:$CI_COMMIT_SHA
  only:
    - branches

integration-tests:
  stage: test
  image: docker:24
  services:
    - docker:24-dind
    - postgres:15-alpine
    - redis:7-alpine
  variables:
    POSTGRES_HOST_AUTH_METHOD: trust
  script:
    # Wait for services
    - apk add --no-cache postgresql-client
    - until pg_isready -h postgres -U $POSTGRES_USER; do sleep 2; done
    
    # Run tests
    - |
      docker run --rm \
        --network host \
        -e DATABASE_URL=postgresql://$POSTGRES_USER:$POSTGRES_PASSWORD@postgres:5432/$POSTGRES_DB \
        -e REDIS_URL=redis://redis:6379 \
        -v $CI_PROJECT_DIR/test-results:/results \
        $CI_REGISTRY_IMAGE/test-runner:$CI_COMMIT_SHA
  artifacts:
    when: always
    reports:
      junit: test-results/junit.xml
    paths:
      - test-results/
    expire_in: 1 week

docker-compose-tests:
  stage: test
  image: docker/compose:latest
  services:
    - docker:24-dind
  script:
    - docker-compose -f docker-compose.test.yml up --abort-on-container-exit --exit-code-from tests
  after_script:
    - docker-compose -f docker-compose.test.yml logs > docker-logs.txt
    - docker-compose -f docker-compose.test.yml down -v
  artifacts:
    when: on_failure
    paths:
      - docker-logs.txt
    expire_in: 3 days

k8s-integration-tests:
  stage: test
  image: google/cloud-sdk:alpine
  script:
    # Install kubectl
    - curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
    - chmod +x kubectl
    - mv kubectl /usr/local/bin/
    
    # Deploy to test cluster
    - kubectl config use-context test-cluster
    - kubectl apply -f k8s/test-namespace.yaml
    - kubectl apply -f k8s/ -n testing
    - kubectl wait --for=condition=complete job/integration-tests -n testing --timeout=10m
    
    # Collect results
    - kubectl logs job/integration-tests -n testing > k8s-test-output.log
  after_script:
    - kubectl delete namespace testing --ignore-not-found=true
  artifacts:
    when: always
    paths:
      - k8s-test-output.log
    expire_in: 1 week
  only:
    - main
    - develop

pipeline {
    agent any
    
    environment {
        DOCKER_REGISTRY = 'registry.example.com'
        IMAGE_NAME = 'test-runner'
        IMAGE_TAG = "${env.BUILD_NUMBER}"
    }
    
    stages {
        stage('Build Test Image') {
            steps {
                script {
                    docker.build("${DOCKER_REGISTRY}/${IMAGE_NAME}:${IMAGE_TAG}", "-f Dockerfile.test .")
                }
            }
        }
        
        stage('Integration Tests') {
            steps {
                script {
                    docker.image('postgres:15-alpine').withRun('-e POSTGRES_PASSWORD=testpass -e POSTGRES_USER=testuser -e POSTGRES_DB=testdb') { db ->
                        docker.image('redis:7-alpine').withRun() { redis ->
                            // Wait for services
                            sh 'sleep 10'
                            
                            // Run tests
                            docker.image("${DOCKER_REGISTRY}/${IMAGE_NAME}:${IMAGE_TAG}").inside("--link ${db.id}:postgres --link ${redis.id}:redis") {
                                sh '''
                                    export DATABASE_URL=postgresql://testuser:testpass@postgres:5432/testdb
                                    export REDIS_URL=redis://redis:6379
                                    pytest -v --junitxml=test-results/junit.xml
                                '''
                            }
                        }
                    }
                }
            }
        }
        
        stage('Docker Compose Tests') {
            steps {
                sh '''
                    docker-compose -f docker-compose.test.yml up --abort-on-container-exit --exit-code-from tests
                '''
            }
            post {
                always {
                    sh 'docker-compose -f docker-compose.test.yml logs > docker-logs.txt'
                    sh 'docker-compose -f docker-compose.test.yml down -v'
                }
            }
        }
        
        stage('Publish Results') {
            steps {
                junit 'test-results/junit.xml'
                publishHTML([
                    reportDir: 'test-results',
                    reportFiles: 'report.html',
                    reportName: 'Test Report'
                ])
            }
        }
    }
    
    post {
        failure {
            archiveArtifacts artifacts: 'docker-logs.txt', allowEmptyArchive: true
        }
        cleanup {
            cleanWs()
        }
    }
}

# Build stage
FROM node:18 AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build

# Test stage
FROM node:18-alpine AS test
WORKDIR /app
COPY --from=builder /app/node_modules ./node_modules
COPY --from=builder /app/dist ./dist
COPY package*.json ./
RUN npm install --only=dev
CMD ["npm", "test"]

# Final minimal image
FROM node:18-alpine
WORKDIR /app
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
USER node
CMD ["node", "dist/index.js"]

# Resource limits for predictable performance
services:
  test-runner:
    deploy:
      resources:
        limits:
          cpus: '2'
          memory: 2G
        reservations:
          cpus: '1'
          memory: 1G
    # Prevent OOM killer
    oom_kill_disable: true
    # Set memory swappiness
    sysctls:
      - vm.swappiness=10

import pytest
from testcontainers.postgres import PostgresContainer

@pytest.fixture(scope="function")  # New container per test
def isolated_database():
    with PostgresContainer("postgres:15") as postgres:
        # Each test gets a fresh database
        yield postgres
        # Automatic cleanup after test

def test_with_isolation_1(isolated_database):
    # Test 1 with clean database
    pass

def test_with_isolation_2(isolated_database):
    # Test 2 with clean database (no interference)
    pass

# Access running container
docker-compose exec tests /bin/sh

# View logs in real-time
docker-compose logs -f tests

# Inspect container filesystem
docker-compose exec tests ls -la /app

# Check environment variables
docker-compose exec tests env

# Debug networking
docker-compose exec tests ping database
docker-compose exec tests nslookup database

# Keep container running after test failure
docker-compose run --rm tests /bin/sh

import time
import psutil
from testcontainers.core.container import DockerContainer

def monitor_container_resources(container: DockerContainer):
    stats = container.get_wrapped_container().stats(stream=False)
    
    cpu_percent = stats['cpu_stats']['cpu_usage']['total_usage']
    memory_usage = stats['memory_stats']['usage'] / (1024 * 1024)  # MB
    
    print(f"CPU Usage: {cpu_percent}%")
    print(f"Memory Usage: {memory_usage:.2f} MB")

@pytest.fixture
def monitored_container():
    container = DockerContainer("myapp:latest")
    container.start()
    
    yield container
    
    # Print resource usage after test
    monitor_container_resources(container)
    container.stop()