Using Docker Compose for Back Ends

1. Introduction

Docker Compose is a tool that simplifies the management of multi-container Docker applications. It allows developers to define services, networks, and volumes in a single YAML file, making it easier to deploy and manage back-end services.

2. Key Concepts

3. Installation

To use Docker Compose, ensure you have Docker installed on your machine. You can install Docker Compose by following the instructions on the official documentation.

4. Creating a Docker Compose File

Create a file named docker-compose.yml in your project root. Below is a basic example for a Node.js and MongoDB application:

version: '3.8'

services:
  web:
    image: node:14
    working_dir: /app
    volumes:
      - .:/app
    ports:
      - "3000:3000"
    depends_on:
      - mongo
    environment:
      - MONGO_URI=mongodb://mongo:27017/mydb

  mongo:
    image: mongo:4.4
    volumes:
      - mongo-data:/data/db

volumes:
  mongo-data:

5. Running the Application

To start your application, navigate to your project directory in the terminal and run:

docker-compose up

This command will build the services defined in the docker-compose.yml file and start the containers. You can stop the application using Ctrl+C or by running:

docker-compose down

6. Best Practices

• Use `.env` files to store environment variables securely.
• Keep your Docker images small to improve performance.
• Leverage Docker Compose versioning to maintain compatibility.
• Define clear dependencies between services using depends_on.
• Regularly clean up unused containers and images with docker system prune.

7. FAQ