Elixir/Phoenix on Alpine Linux
This Dockerfile provides everything you need to run your Phoenix application in Docker out of the box.
It is based on my
alpine-erlang image, and installs Elixir (1.6.4), Node.js (6.10.x), Hex and Rebar. It can handle compiling
your Node and Elixir dependencies as part of it's build.
NOTE: This image is intended to run in unprivileged environments, it sets the home directory to
/opt/app, and makes it globally
read/writeable. If run with a random, high-index user account (say 1000001), the user can run an app, and that's about it. If run
with a user of your own creation, this doesn't apply (necessarily, you can of course implement the same behaviour yourself).
It is highly recommended that you add a
USER default instruction to the end of your Dockerfile so that your app runs in a non-elevated context.
To boot straight to a prompt in the image:
$ docker run --rm -it --user=1000001 bitwalker/alpine-elixir-phoenix iex Erlang/OTP 20 [erts-9.1.3] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:10] [hipe] [kernel-poll:false] Interactive Elixir (1.6.4) - press Ctrl+C to exit (type h() ENTER for help) iex(1)>
Extending for your own application:
FROM bitwalker/alpine-elixir-phoenix:latest # Set exposed ports EXPOSE 5000 ENV PORT=5000 MIX_ENV=prod # Cache elixir deps ADD mix.exs mix.lock ./ RUN mix do deps.get, deps.compile # Same with npm deps ADD assets/package.json assets/ RUN cd assets && \ npm install ADD . . # Run frontend build, compile, and digest assets RUN cd assets/ && \ npm run deploy && \ cd - && \ mix do compile, phx.digest USER default CMD ["mix", "phx.server"]
It is recommended when using this that you have the following in
.dockerignore when running
_build deps assets/node_modules test
This will keep the payload smaller and will also avoid any issues when compiling dependencies.