Blog / 2020 / April / 24

Docker Compose

April 24, 2020

I wanted to have three docker containers that were managed as one, being spun up and torn down together. These were a postgres database, pgsql postgres admin tool, and a spring boot back end (the one from https://drumcoder.co.uk/blog/2020/apr/24/docker-spring-boot/)

docker-compose.yml

Here's the docker-compose.yml file I used:

version: "3"
services:
  todo-backend:
    image: drumcoder/todo-backend:latest
    container_name: todo-backend
    depends_on:
      - todo-db
    ports:
      - 5400:8080
  db-admin:
    image: dpage/pgadmin4:latest
    container_name: todo-pgadmin
    environment:
      - PGADMIN_DEFAULT_EMAIL=email@here.com
      - PGADMIN_DEFAULT_PASSWORD=sekr1t
    depends_on:
      - todo-db
    ports:
      - 7777:80
  todo-db:
    image: postgres:latest
    container_name: todo-db
    environment:
      - POSTGRES_DB=todo
      - POSTGRES_USER=todo
      - POSTGRES_PASSWORD=sekr1t
    ports:
      - 5432:5432

Once setup, all three the containers can be spun up using docker-compose up.

The database connection inside the spring boot app was set to use:

spring.datasource.url = jdbc:postgresql://todo-db:5432/todo
spring.datasource.username = todo
spring.datasource.password = sekr1t

Note the use of the container name to be able to refer to the host for the database.

Docker compose will create a separate virtual network and run all these components inside of it. This can be viewed using docker network ls

NETWORK ID          NAME                DRIVER              SCOPE
2ae18094fbe2        bridge              bridge              local
8045e0043cc0       host                host                local
ea14b8e7f412        none                null                local
ce389a7c2478        todo_default        bridge              local

Tags: docker dockercompose postgres