docker-compose.yml

version: '2'

services:
    # the first container will be called postgres
    postgres:
        # install the official postgres image with postgis installed 
        image: mdillon/postgis
        # the volumes allow us to have a shared space between our computer and the docker vm
        volumes:
            - "./.data/postgres:/var/lib/postgresql"
         # set up environment variable for the postgres instance
        environment:
            POSTGRES_USER: ${PSQL_USER}
            POSTGRES_PASSWORD: ${PSQL_PWD}
            POOL: 16
        # the port to listen
        ports:
            - "5432:5432"
    # our last container is called elixir
    elixir:
        # build use a path to a Dockerfile
        build: .
        # we set multiple ports as each of our application (but database) will use a different port
        ports:
            - "4000:4000"
            - "4002:4002"
        # we share the entire app with the container, but the libs
        volumes:
            - ".:/app"
            - "/app/deps"
            - "/app/apps/admin/assets/node_modules"
        # the container will not start if the postgres container isn't running
        depends_on:
            - postgres
        # set up environment variable for the phoenix instance 
        environment:
            POSTGRES_USER: ${PSQL_USER}
            POSTGRES_PASSWORD: ${PSQL_PWD}
            POSTGRES_DB_TEST: ${PSQL_DB_TEST}
            POSTGRES_DB_DEV: ${PSQL_DB}
            POSTGRES_HOST: ${PSQL_HOST}