Time and thoughts

I mostly code in Ruby. And I tend to bootstrap lots of project to test out my ideas. I create lots of projects, and experiment different languages and frameworks and docker helps to keep them segragated and help in managing the dependencies easily. Though it has limitations on mac I still tend to use it.

I was trying to get started with a Phoenix app and thougth this might help others as well. It has been taken from multiple places and helps me get started quickly.

I have the following Dockerfile and docker-compose.yml

Dockerfile

# ./Dockerfile

# Extend from the official Elixir image
FROM elixir:latest

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

RUN curl -sL https://deb.nodesource.com/setup_12.x | bash -
RUN apt-get install -y nodejs

# Create app directory and copy the Elixir projects into it
ADD . /app
WORKDIR /app

RUN mix local.hex --force
RUN mix archive.install --force https://github.com/phoenixframework/archives/raw/master/phx_new.ez

EXPOSE 4000
CMD ["./entrypoint.sh"]

docker-compose.yml

version: '3'

services:
  web:
    build: .
    ports:
      - "4000:4000"
    volumes:
      - .:/app
    depends_on:
      - db
  db:
    image: postgres:9.6

You will notice that I have used a file called entrypoint.sh. It has the following content:

entrypoint.sh

#!/bin/bash

# Wait for Postgres to become available.
until psql -h db -U "postgres" -c '\q' 2>/dev/null; do
  >&2 echo "Postgres is unavailable - sleeping"
  sleep 1
done

mix ecto.migrate
mix phx.server

Let us assume that I want to create a project called mvp-app. Create a directory called the same and put these three files inside it.

To init the app run the following commands:

$ docker-compose up
$ docker-compose run --rm web mix phx.new mvp-app

The first one should exit (may be with some error, I dont remember). The second one will create another directory called mvp-app inside the current directory. Move all the contents inside the new directory to its parent and delete the new one.

You can continue with what Phoenix suggests to continue setting up the project:

$ docker-compose run --rm web mix ecto.create
$ docker-compose run --rm web mix ecto.migrate

Once you are done with this the initial landing page will be visible with simple

$ docker-compose up

Once you have the containers running you can use exec instead of run in docker-compose.

You can generate models like this

$ docker-compose exec web mix ecto.gen.migration add_information

and run migration as mention before, may be with exec this time!

To access you can visit localhost:4000 on you browser. Dont forget to git init :)