Docker base image for Ruby on Rails applications.
I am using https://github.com/jwilder/docker-register so only one port is allowed to be exported. Only port EXPOSE_PORT (e.g. 80) is exposed if additionally ssl is needed the proxy (e.g. nginx) has to handle the ssl part.
Some basics are based on the good work of: https://github.com/phusion/passenger-docker
In order to use this image you need to set these environment variables:
RAILS_ENV EXPOSE_PORT PROCESS_TYPE
The RAILS_ENV is set as rails environment in the app. The EXPOSE_PORT is the port the container exposes the http server on. Due to the usage of docker-register/docker-discover each app needs to be on a separate port.
All apps exposing the same port will be mapped as additional server for the same app.
The PROCESS_TYPE environment variable can be set to "web" or "background_worker". If it is set to web passenger will be started and serve the app. If set to background_worker it will start a background processing service.
Per default it will start sidekiq as a background worker. If you want to use another service put a file with a content like:
#!/bin/bash set -e cd /home/app/webapp exec bundle exec sidekiq -e $RAILS_ENV
This file needs to put to the folder: /etc/service/background_worker/run.
In a Dockerfile you can use
ADD my_own_background_worker.sh /etc/service/background_worker/run
For a rails app you can create a Dockerfile with this content:
FROM mikepetersen/passenger-docker:latest MAINTAINER Mike Petersen "firstname.lastname@example.org" # Set correct environment variables. ENV HOME /home/app/webapp # Use baseimage-docker's init system. CMD ["/sbin/my_init"] # Start Nginx / Passenger RUN rm -f /etc/service/nginx/down # Remove the default site RUN rm /etc/nginx/sites-enabled/default # Prepare folders RUN mkdir /home/app/webapp # Add the rails app ADD . /home/app/webapp WORKDIR /home/app/webapp RUN chown -R app:app /home/app/webapp RUN sudo -u app bundle install --deployment RUN bundle exec rake assets:precompile # Clean up APT when done. RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*