Part 4: Docker with rails, postgres(database which is running inside the docker)

Please follow the basic steps from here and i’m listing here only the changes for running postgres service inside the docker, still it store the data in local disk.

database.yml

default: &default
  adapter: postgresql
  encoding: utf8
  pool: 5
  username: name
  password: password
  host: db

development:
  <<: *default
  database: project_db1

test:
  <<: *default
  database: docc

production:
  <<: *default
  database: docc

Different from the previous file is host: db

Dockerfile (No change in this file)

FROM ruby:2.4.0
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
RUN mkdir /myapp
WORKDIR /myapp
COPY . /myapp
RUN bundle install

docker-compose.yml

version: '3'
services:
  db:
    image: postgres
    ports:
      - "5432"
    volumes:
      - /usr/data/volumes/pgdata/etc:/etc/postgresql
      - /usr/data/volumes/pgdata/log:/var/log/postgresql
      - /usr/data/volumes/pgdata/data:/var/lib/postgresql/data
  web:
    build: .
    command: bundle exec rails s -p 3000 -b '0.0.0.0'
    volumes:
      - .:/myapp
    ports:
      - "3000:3000"
    depends_on:
      - db

changes here

ports:
      - "5432"
    volumes:
      - /usr/data/volumes/pgdata/etc:/etc/postgresql
      - /usr/data/volumes/pgdata/log:/var/log/postgresql
      - /usr/data/volumes/pgdata/data:/var/lib/postgresql/data

which will copy the content from docker location to local location.

docker location : /etc/postgresql

local location : /usr/data/volumes/pgdata/etc

Once all set.. try

$ sudo docker-compose run web bundle exec rake db:create
$ sudo docker-compose run web bundle exec rake db:migrate
& sudo docker-compose up

Sample rails repo found at github

Previous : Part 3: Docker with rails, postgres

back to docker Series