About this Repo

This is the Git repo of the Docker official image for [rails] (https://registry.hub.docker.com/_/rails/) and mysql. See these page for the full readme on how to use this Docker image and for information regarding contributing and issues.

Pre-Requirements

First install docker, docker compose for your machine and start it. How this is done is very well documented all over the internet.

Build the project

You need generate the Rails skeleton app using docker-compose run:

$ docker-compose run app rails new . --force --database=mysql --skip-bundle

Compose will build the image for the web service using the Dockerfile. Then it’ll run rails new inside a new container, using that image. Once it’s done, you should have generated a fresh app:

 $ ls -l
total 56
-rw-r--r--   1 user  staff   488 Nov 22 22:02 Dockerfile
-rw-r--r--   1 user  staff  1521 Nov 22 01:36 Gemfile
-rw-r--r--   1 user  staff  4006 Nov 22 01:36 Gemfile.lock
-rw-r--r--   1 user  staff   478 Nov 22 01:17 README.rdoc
-rw-r--r--   1 user  staff   249 Nov 22 01:17 Rakefile
drwxr-xr-x   8 user  staff   272 Nov 22 01:36 app
drwxr-xr-x   7 user  staff   238 Nov 22 01:36 bin
drwxr-xr-x  11 user  staff   374 Nov 22 10:38 config
-rw-r--r--   1 user  staff   153 Nov 22 01:17 config.ru
drwxr-xr-x   5 user  staff   170 Nov 22 10:46 db
-rw-r--r--   1 user  staff   420 Nov 22 22:02 docker-compose.yml
drwxr-xr-x   4 user  staff   136 Nov 22 01:36 lib
drwxr-xr-x   4 user  staff   136 Nov 22 01:39 log
drwxr-xr-x   7 user  staff   238 Nov 22 01:36 public
drwxr-xr-x   9 user  staff   306 Nov 22 01:27 test
drwxr-xr-x   6 user  staff   204 Nov 22 01:39 tmp
drwxr-xr-x   3 user  staff   102 Nov 22 01:36 vendor

Now that you’ve got rails app, you need to build the image again.

docker-compose build

Connect the database

The app is now bootable, but you’re not quite there yet. By default, Rails expects a database to be running on localhost - so you need to point it at the mysql container instead. You also need to change the database and username to align with the defaults set by the mysql image.

Replace the contents of config/database.yml with the following:

default: &default
  adapter: mysql2
  encoding: utf8
  pool: 5
  username: root
  password: "root"
  host: mysql

development:
  <<: *default
  database: dev

test:
  <<: *default
  database: dev

You can now boot the app with:

docker-compose up -d

Finally, you need to create the database. In another terminal, run:

docker-compose run app rake db:create

That’s it. Your app should now be running on port 3000 on your Docker daemon. If you’re using Docker Machine, then docker-machine ip MACHINE_VM returns the Docker host IP address.

$ docker-machine ip default
192.168.99.100

http://192.168.99.100:3000/

To stop container then run following command:

$ docker-compose stop
Stopping ror_app_1 ... done
Stopping ror_mysql_1 ... done

To start container again then run following command:

$ docker-compose start
Starting dbdata ... done
Starting appdata ... done
Starting mysql ... done
Starting app ... done