two-tier-flask-app-docker-testing

Dockerfile

# Use an official Python runtime as the base image
FROM python:3.9-slim

# Set the working directory in the container
WORKDIR /app

# install required packages for system
RUN apt-get update \
    && apt-get upgrade -y \
    && apt-get install -y gcc default-libmysqlclient-dev pkg-config \
    && rm -rf /var/lib/apt/lists/*

# Copy the requirements file into the container
COPY requirements.txt .

# Install app dependencies
RUN pip install mysqlclient
RUN pip install --no-cache-dir -r requirements.txt

# Copy the rest of the application code
COPY . .

# Specify the command to run your application
CMD ["python", "app.py"]

docker-compose

version: "3.8"
services:
  mysql:
    container_name: mysql
    image: mysql
    environment:
      MYSQL_DATABASE: devops
      MYSQL_ROOT_PASSWORD: root
    ports:
      - "3306:3306"
    volumes:
      - ./mysql-data:/var/lib/mysql
    networks:
      - mynetwork
    restart: always
    healthcheck:
      test: ["CMD", "mysqladmin", "ping", "-h", "localhost", "-uroot", "-proot"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 60s

  flask:
    build:
      context: .
    container_name: two-tier-app
    ports:
      - "5000:5000"
    environment:
      MYSQL_HOST: mysql
      MYSQL_USER: root
      MYSQL_PASSWORD: root
      MYSQL_DB: devops
    networks:
      - mynetwork
    depends_on:
      - mysql
    restart: always
    healthcheck:
      test: ["CMD-SHELL", "curl -f http://localhost:5000/health || exit 1"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 30s

volumes:
  mysql-data:

networks:
  mynetwork:

Docker-multi

# ------------------- Stage 1: Build Stage ------------------------------
FROM python:3.9 AS builder

WORKDIR /app

# Install build dependencies
RUN apt-get update && \
    apt-get install -y --no-install-recommends gcc default-libmysqlclient-dev pkg-config && \
    rm -rf /var/lib/apt/lists/*

# Copy and install Python dependencies
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

# ------------------- Stage 2: Final Stage ------------------------------
FROM python:3.9-slim

WORKDIR /app

# Install runtime dependencies only
RUN apt-get update && \
    apt-get install -y --no-install-recommends libmariadb3 && \
    rm -rf /var/lib/apt/lists/*

# Copy dependencies and application code from the builder stage
COPY --from=builder /usr/local/lib/python3.9/site-packages/ /usr/local/lib/python3.9/site-packages/
COPY . .

CMD ["python", "app.py"]