Dockerfile

# Set the Docker image you want to base your image off.
# I chose this one because it has Elixir preinstalled.
FROM trenpixster/elixir:1.3.0

# Setup Node - Phoenix uses the Node library `brunch` to compile assets.
# The official node instructions want you to pipe a script from the 
# internet through sudo. There are alternatives: 
# https://www.joyent.com/blog/installing-node-and-npm
RUN curl -sL https://deb.nodesource.com/setup_5.x | sudo -E bash - && apt-get install -y nodejs

# Install other stable dependencies that don't change often

# Compile app
RUN mkdir /app
WORKDIR /app

# Install Elixir Deps
ADD mix.* ./
RUN MIX_ENV=prod mix local.rebar
RUN MIX_ENV=prod mix local.hex --force
RUN MIX_ENV=prod mix deps.get

# Install Node Deps
ADD package.json ./
RUN npm install

# Install app
ADD . .
RUN MIX_ENV=prod mix compile
RUN MIX_ENV=prod mix phoenix.digest

# Compile assets
RUN NODE_ENV=production node_modules/brunch/bin/brunch build --production
RUN MIX_ENV=prod mix phoenix.digest

# Exposes this port from the docker container to the host machine
EXPOSE 4000

# The command to run when this image starts up
CMD MIX_ENV=prod mix phoenix.server