Docker Compose

 Compose is a tool for defining and running multi-container Docker applications. With Compose, you use a YAML file to configure your application’s services. Then, with a single command, you create and start all the services from your configuration.

Using Compose is basically a three-step process:

1. Define your app’s environment with a Dockerfile so it can be reproduced anywhere.

2. Define the services that make up your app in docker-compose.yml so they can be run together in an isolated environment.

3. Run docker-compose up and Compose starts and runs your entire app.

Install Docker compose file

sudo curl -L "https://github.com/docker/compose/releases/download/1.23.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

chmod +x /usr/local/bin/docker-compose

docker-compose --version

Example -1

version: '3.3'

services:

   db:

     image: mysql:5.7

     volumes:

       - db_data:/var/lib/mysql

     restart: always

     environment:

       MYSQL_ROOT_PASSWORD: somewordpress

       MYSQL_DATABASE: wordpress

       MYSQL_USER: wordpress

       MYSQL_PASSWORD: wordpress

   wordpress:

     depends_on:

       - db

     image: wordpress:latest

     ports:

       - "8000:80"

     restart: always

     environment:

       WORDPRESS_DB_HOST: db:3306

       WORDPRESS_DB_USER: wordpress

       WORDPRESS_DB_PASSWORD: wordpress

       WORDPRESS_DB_NAME: wordpress

volumes:

    db_data: {}

docker-compose up -d

docker-compose down

Example -2

version: '3.3'

services:

   db:

     image: ramansharma95/mysql

   webapp:

     image: ramansharma95/webapp

     ports:

       - "84:80"

Run the following command in mysql :

container (docker exec -it <<containerid>> bash) mysql -u root -p whizlabs

create database company;

use company;

create table employee ( name varchar(30), mobile varchar(30));

select * from employee;