Install and setup for the Docker Compose

Hello DevOps enthusiast, In this post, We will discuss docker-compose why we need and how it can resolve the multi-container application issues. What is it's limitations?

How Docker-compose works?

What is Docker-compose? why?

If we are working on multi-container apps then it is a hassle because we would be doing repeatedly the following tasks:

• Build images from Dockerfiles 
• Pull images from the Hub or a private registry 
• Configure and create multiple containers for each service required to run the application
• Start and stop containers individually each one
• Stream their logs to check the status and troubleshoot

In contrast to all the above hassles, The Docker compose developed as best tool for defining & running multi-container docker applications. We can use YAML files to configure application services (docker-compose.yml) Simplified control for multi-container applications - we can start all services with a single command: docker compose up and can stop all services with a single command: docker compose down

Docker-compose can be used to scale up selected services when required

Features of docker-compose

• We can define and run multi-containerized Docker applications where it could be database, web server, proxy containers to run the complete application.
• Docker-compose uses single YAML file to configure all applications dependent services
• The docker-compose is powerful with a single command, we can create and start all the services from the configuration.
• Mainly for dev and test environments can be used for repetitive tasks which deals with Docker containers 
• We can build multiple isolated environments on a single host
• It preserves volume data when containers are created using docker-compose.yaml file.
• Docker-compose has a wonderful feature that, Only recreate containers that have changes
• We could define the variables and moving a composition between environments such as development to test or staging.

Installing Docker-compose

There are two ways to install the docker-compose :

1.  Using GitHub
2.  Using pip install 

Using GitHub download 

Step 1: Run the following curl command to download from the GitHub the current stable release of Docker-compose
Old compose worked! But it don't support all compose versions.

sudo curl -L https://github.com/docker/compose/releases/download/1.3.2/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose 

Better option to use latest version always! take the stable version from the GitHub

sudo curl -L https://github.com/docker/compose/releases/download/v2.2.3/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose 

Step 2: Apply executable permissions to the docker-compose binary:

ls -l /usr/local/bin/docker-compose #You must be in root user
chmod +x /usr/local/bin/docker-compose 
ls -l /usr/local/bin/docker-compose #Ensure the docker-compose file have execute permissions

Step 3: set the ENV var with the latest path in the bashrc or .bashprofile

echo "export PATH=$PATH:/usr/local/bin" >> .bashrc

Step 4: Check the version of docker-compose command

docker-compose -v

Install docker-compose using GitHub download

Best References for docker-compose:

• Docker compose file using dockerfile
• Test the application with docker-compose