Elixir docker skeleton

docker-compose.yml

# Version of docker-compose
version: '3'

# Containers we are going to run
services:
  # Our Phoenix container
  phoenix:
    # The build parameters for this container.
    build:
      # Here we define that it should build from the current directory
      context: .
    environment:
      # Variables to connect to our Postgres server
      PGUSER: postgres
      PGPASSWORD: postgres
      PGDATABASE: database_name
      PGPORT: 5432
      # Hostname of our Postgres container
      PGHOST: db
    ports:
      # Mapping the port to make the Phoenix app accessible outside of the container
      - "4000:4000"
    depends_on:
      # The db container needs to be started before we start this container
      - db
  db:
    # We use the predefined Postgres image
    image: postgres:9.6
    environment:
      # Set user/password for Postgres
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      # Set a path where Postgres should store the data
      PGDATA: /var/lib/postgresql/data/pgdata
    restart: always
    volumes:
      - pgdata:/var/lib/postgresql/data
# Define the volumes
volumes:
  pgdata:

Dockerfile

# Use an official Elixir runtime as a parent image
FROM elixir:latest

RUN apt-get update && \
  apt-get install -y postgresql-client

# Create app directory and copy the Elixir projects into it
RUN mkdir /app
COPY . /app
WORKDIR /app

# Install hex package manager
RUN mix local.hex --force

RUN mix deps.get

RUN mix local.rebar --force

# Compile the project
RUN mix do compile

CMD ["/app/entrypoint.sh"]

entrypoint.sh

# entrypoint.sh

#!/bin/bash
# Docker entrypoint script.

# Wait until Postgres is ready
while ! pg_isready -q -h $PGHOST -p $PGPORT -U $PGUSER
do
  echo "$(date) - waiting for database to start"
  sleep 2
done

# Create, migrate, and seed database if it doesn't exist.
if [[ -z `psql -Atqc "\\list $PGDATABASE"` ]]; then
  echo "Database $PGDATABASE does not exist. Creating..."
  createdb -E UTF8 $PGDATABASE -l en_US.UTF-8 -T template0
  mix ecto.migrate
  mix run priv/repo/seeds.exs
  echo "Database $PGDATABASE created."
fi

exec mix phx.server