An Implementation of Docker for Serial Rails Development and Deployment.

database.yml

development:
  adapter: postgresql
  database: railsapp_development
  username: docker
  host: <%= ENV['DB_PORT_5432_TCP_ADDR'] %>
  port: 5432
  template: template0
  pool: 5
  timeout: 5000

test:
  adapter: postgresql
  database: railsapp_test
  username: docker
  host: <%= ENV['DB_PORT_5432_TCP_ADDR'] %>
  port: 5432
  template: template0
  pool: 5
  timeout: 5000

production:
  adapter: postgresql
  database: railsapp_production
  username: docker
  host: <%= ENV['DB_PORT_5432_TCP_ADDR'] %>
  port: 5432
  template: template0
  pool: 5
  timeout: 5000

Dockerfile_base

FROM ubuntu:14.10
MAINTAINER Thom Parkin, [email protected]

# Rails with Nginx and Passenger - Read the article on RubySource.com

# Update local OS
RUN apt-get update
RUN apt-get upgrade -y

# Install dependencies
RUN apt-get install -y git-core wget curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev python-software-properties

## Install Ruby 2.1.3
RUN mkdir ~/ruby
WORKDIR ~/ruby
RUN wget http://cache.ruby-lang.org/pub/ruby/2.1/ruby-2.1.3.tar.gz
RUN tar -xzvf ruby-2.1.3.tar.gz
WORKDIR ruby-2.1.3
RUN ./configure
RUN make
RUN make install
RUN rm -rf ~/ruby && ruby -v
RUN echo "gem: --no-ri --no-rdoc" > ~/.gemrc
RUN gem install bundler rails --no-ri --no-rdoc
WORKDIR ~/

# Add a default Rails application to use for "smoke test"
ADD ./ /opt/
WORKDIR /opt/dockerapp
ENV RAILS_ENV production
RUN bundle install

# Install Phusion's PGP key to verify packages
RUN gpg --keyserver keyserver.ubuntu.com --recv-keys 561F9B9CAC40B2F7
RUN gpg --armor --export 561F9B9CAC40B2F7 | sudo apt-key add -

# Add HTTPS support to APT
RUN apt-get install apt-transport-https

# Add the passenger repository
RUN sh -c "echo 'deb https://oss-binaries.phusionpassenger.com/apt/passenger trusty main' >> /etc/apt/sources.list.d/passenger.list"
RUN chown root: /etc/apt/sources.list.d/passenger.list
RUN chmod 600 /etc/apt/sources.list.d/passenger.list
RUN apt-get update

# Install nginx and passenger
RUN apt-get install -y nginx-full passenger
RUN service nginx start

RUN sed -i 's/# passenger_root /passenger_root /' /etc/nginx/nginx.conf
RUN sed -i 's/# passenger_ruby.*;/passenger_ruby \/usr\/local\/bin\/ruby;/' /etc/nginx/nginx.conf

# nginx configuration
ADD nginx.conf /etc/nginx/sites-enabled/default

# Restart nginx service
CMD sudo service nginx restart

EXPOSE 80

Dockerfile_generic

FROM rails_passenger_nginx:1.0
MAINTAINER Thom Parkin, [email protected]

# Add Rails app
ADD . /opt/
ENV RAILS_ENV production

# bundle install
WORKDIR /opt/YOUR_RAILS_APPLICATION
RUN bash -l -c "bundle install"
RUN rake db:create db:migrate

# nginx configuration
ADD nginx.conf /etc/nginx/sites-enabled/default
RUN sed -i 's/XXX.XXX.XXX.XXX/SERVERNAME_OR_IPADDRESS/' /etc/nginx/sites-enabled/default
RUN sed -i 's/RAILS_APP_NAME/YOUR_RAILS_APPLICATION/' /etc/nginx/sites-enabled/default

# Restart nginx service
CMD sudo service nginx restart

EXPOSE 80

InstallDocker.md

Working with Docker on a Linux Server

If you are interested in working with Docker I strongly recommend using Digital Ocean's hosting solution. They offer a 'Docker' plan; which means it already has all the required software and dependencies.

Otherwise, here are instructions for installing Docker on an Ubuntu 14.04 LTS server (which you can also get from Digital Ocean):

$ apt-get update
$ apt-get -y install docker.io
# fix paths
$ ln -sf /usr/bin/docker.io /usr/local/bin/docker
$ sed -i '$acomplete -F _docker docker' /etc/bash_completion.d/docker.io
# configure Docker to start when the server boots
$ update-rc.d docker.io defaults

nginx,conf

server {
        listen 80 default_server;
        listen [::]:80 default_server ipv6only=on;

        server_name XXX.XXX.XXX.XXX;
        passenger_enabled on;
        rails_env    production;
        root         /opt/RAILS_APP_NAME/public;

        # redirect server error pages to the static page /50x.html
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
}

UpdateDocker.md

Docker is changing rapidly. I found this list of steps to upgrade docker:

$ wget -qO- https://get.docker.io/gpg | sudo apt-key add -
$ sudo sh -c "echo deb http://get.docker.io/ubuntu docker main > /etc/apt/sources.list.d/docker.list"
$ sudo apt-get update
$ sudo apt-get install lxc-docker
$ docker -v