Prepare
We want to deploy our rails app to a doker container and do this automatically with gitlab-ci, so let's start.
First we pre-build a docker image, that we would use for our rails container.
We also include nodejs and yarn. as our rails app has Javascript components written in Js
Dockerfile
FROM ruby:3.0
RUN apt-get update -y
RUN gem install bundler
RUN gem install rake
RUN apt-get install -y sudo curl wget git
RUN curl -sL https://deb.nodesource.com/setup_12.x | sudo -E bash -
RUN apt-get install -y nodejs
RUN npm install -g yarn
RUN apt-get install -y zlib1g-dev libpng-dev libssl-dev
RUN ruby -v
VOLUME ["/app"]
WORKDIR /app
and now let's build an image with docker build -t rails:1 .
Prepare Docker
first create a docker-compose.yml with our container config
services:
rails-app:
user: ${CURRENT_UID}
build: .
volumes:
- .:/app
ports:
- "3000:3000"
volumes:
- /docker/volumes/rails-app:/app
command:
- ./docker-run.sh
docker-run.sh is our entry script. In the project - the name of the file is docker-run-raw.sh, later on we would rename it. We should do this because of executable flags.
here docker-run-raw.sh:
#!/bin/sh
set -e
# YARN, Precompile
yarn install --network-concurrency 1
NODE_ENV=production RAILS_ENV=production bundle exec rake assets:precompile
# Start the web server
echo "rm PID"
rm -f tmp/pids/server.pid
echo "starting service"
rails s -p 3000 -b '0.0.0.0' -e production
And we need a Dokerfile, wich we use by the deployment
FROM rails:1
ENV SECRET_KEY_BASE=some_key_here_or_from_environment
COPY . /app
WORKDIR /app
EXPOSE 3000
RUN bundle install
lets deploy it with CI
First we would copy/rsync project to the final destination, give docker-run.sh executable mode and then build our container. Here is the a .gitlab-ci.yaml for this pipeline
variables:
docker_app_root: '/docker/volumes/app'
GIT_STRATEGY: clone
stages:
- deploy
prod-deploy:
stage: deploy
script:
- mkdir -p $docker_app_root
- docker-compose stop
- rsync -r --delete `pwd`/* $docker_app_root
- cd $docker_app_root
- /bin/cp -rf docker-run-raw.sh docker-run.sh
- chmod +x ./docker-run.sh
- CURRENT_UID=$(id -u):$(id -g) docker-compose up --build -d
so now, running a pipeline we habe a working container running on Port 3000 with our Rails Application. Yeha! :))