Setting up CD for a Ruby on Rails project with Bitbucket Pipelines and Docker

Question

I'd love to set up continuous deployment in Bitbucket Pipelines for a Ruby on Rails / PostgreSQL / Sidekiq project, but I'm struggling to get my head around how it all fits together, and specifically how to get postgres working inside a Docker image. I'm very new to Docker and Pipelines.

In my Googling, Docker talks about using docker-compose to create a bundle, so I'd have a Postgres container and a Sideqik container, then link them with the app container. But I'm not sure what the difference is between a bundle and an image, and if Bitbucket Pipelines supports bundles. Eventually I want to set up deployments to a staging environment on Heroku, but for now just getting rspec spec to work in Pipelines would be nice.

Is there an existing public image that has Ruby + PostgreSQL already set up that I can use? If not, where do I start? My current Dockerfile looks like this:

FROM postgres:9.4
FROM ruby:2.3.1-onbuild
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs postgresql-client

I then run docker build . and docker run -it my-image /bin/bash and the following commands:

root@a84ad0e7c16b:/usr/src/app# postgres
bash: postgres: command not found
root@a84ad0e7c16b:/usr/src/app# psql 
psql: could not connect to server: No such file or directory
  Is the server running locally and accepting
  connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?

In a single Dockerfile you shouldn't have 2 FROM commands. The point of docker is that every container is specialized and runs a single (almost) command. You will have a container for Ruby and one for Postgres, eventually one for redis if you are going to use it as a sidekiq backend. Docker-compose is the tool that lets you orchestrate the various containers. Start taking a look here: https://docs.docker.com/compose/rails/ — TopperH, Aug 22 '16 at 21:01

score 2 · Answer 1 · answered Dec 22 '16 at 09:34

Taking the advice from https://bitbucket.org/spittet/ruby-postgresql you could easily setup your bitbucket-pipelines.yml like this:

image: spittet/ruby-postgresql

pipelines:
  default:
    - step:
        script:
          - bundle install
          - /etc/init.d/postgresql start
          - sudo -u postgres sh -c 'createuser root --createdb'
          - rails db:setup RAILS_ENV=test
          - rspec

As you may see I needed to create a user with permissions for creating databases.

For debugging you could try locally first:

run -i -t -v <local_directory_of_your_rails_app>:<directory_on_docker> spittet/ruby-postgresql /bin/bash
cd <directory_on_docker>
bundle install...

score 0 · Answer 2 · answered Jan 08 '17 at 12:50

Docker compose is still not available inside Bitbucket Pipelines, so you'll have to use a single Docker image which has all the dependencies you need already installed.

We've also struggled with finding good Docker container with Django Postgres stack and ended up building custom Docker container. I've described the whole process and steps in a post: Building, Testing and Deploying Django App with Bitbucket Pipelines. You can use it as a template for your project, and replace Python dependencies with Ruby.

Setting up CD for a Ruby on Rails project with Bitbucket Pipelines and Docker

2 Answers2