In Half 2 of our Docker Deep Dive Sequence, we explored Docker pictures and containers. Now, in Half 3, we’ll dive into Docker Compose, a robust software for outlining and managing multi-container functions. Docker Compose permits you to outline complicated functions with a number of companies and dependencies in a single YAML file.

What’s Docker Compose?

Docker Compose is a software that simplifies the method of defining, configuring, and managing multi-container Docker functions. With Docker Compose, you may outline all of your utility’s companies, networks, and volumes in a single docker-compose.yml file. This makes it straightforward to handle complicated functions with a number of parts.

Making a Docker Compose File

Let’s create a easy multi-container utility utilizing Docker Compose. Create a listing to your undertaking, and inside it, create a file named docker-compose.yml with the next content material:

model: '3'
companies:
  internet:
    picture: nginx:alpine
    ports:
      - "80:80"
  app:
    construct: ./myapp
    ports:
      - "4000:80"

On this docker-compose.yml file:

• We outline two companies: internet and app.
• The internet service makes use of an official Nginx picture and maps port 80 – contained in the container to port 80 on the host.
• The app service builds from the ./myapp listing (the place your – Python utility code and Dockerfile are positioned) and maps port 4000 contained in the container to port 80 on the host.

Working the Docker Compose Utility

To start out your multi-container utility utilizing Docker Compose, navigate to the listing containing your docker-compose.yml file and run:

docker-compose up

This command will begin the outlined companies within the foreground, and you’ll entry your Nginx internet server and Python utility as specified within the docker-compose.yml file.

Stopping the Docker Compose Utility

To cease the Docker Compose utility, press Ctrl+C within the terminal the place the companies are working, or you may run:

docker-compose down

It will cease and take away the containers outlined in your docker-compose.yml file.

Conclusion

In Half 3 of the Docker Deep Dive Sequence, we launched Docker Compose, a helpful software for managing multi-container functions. You discovered how you can outline companies, networks, and ports in a docker-compose.yml file and how you can begin and cease a multi-container utility.

Keep tuned for Half 4: Docker Networking, the place we’ll discover Docker’s networking capabilities and how you can join containers collectively.