Managing Microservices with Docker Compose

What is Docker Compose?

Docker Compose is a tool for defining and running multi-container Docker applications using a YAML file. It helps orchestrate containers for different microservices, databases, and external dependencies.

Writing a docker-compose.yml File

Here's an example docker-compose.yml for two microservices:

version: '3.8'

services:
  user-service:
    build: ./user-service
    ports:
      - "5000:5000"

  order-service:
    build: ./order-service
    ports:
      - "5001:5001"

Each service has its own Dockerfile inside its directory. Docker Compose will build and run them together.

Running Multiple Containers

To build and run all services defined in docker-compose.yml:

docker-compose up -d

View running services:

docker-compose ps

Tips & Best Practices

• Use relative paths for local Dockerfile contexts
• Define environment variables in a .env file
• Use named volumes to persist database or cache data
• Define networks explicitly for better control over communication

Example Folder Structure

microservices-app/
├── docker-compose.yml
├── user-service/
│   ├── Dockerfile
│   └── server.js
├── order-service/
│   ├── Dockerfile
│   └── server.js

Docker Compose simplifies the orchestration of microservices by allowing developers to define and manage services in a single file. In the next section, we’ll explore how these services communicate with one another.