docker-composeでmysql+redis+sidekiqなrails環境を作る

• RAILS_ROOT/Gemfile

# これ追加
gem 'sidekiq'
gem 'sinatra', require: false
gem 'redis'
gem 'redis-namespace'

• RAILS_ROOT/config/routes.rb

Rails.application.routes.draw do
  # 2行追加
  require 'sidekiq/web'
  mount Sidekiq::Web => '/sidekiq'

  ...
end

• RAILS_ROOT/config/initializers/sidekiq.rb

Sidekiq.configure_server do |config|
  config.redis = { url: 'redis://redis:6379', namespace: "sidekiq" }
end

Sidekiq.configure_client do |config|
  config.redis = { url: 'redis://redis:6379', namespace: "sidekiq" }
end

• RAILS_ROOT/config/database.yml

default: &default
  adapter: mysql2
  encoding: utf8
  pool: 5
  username: root
  password: password # ここ修正
  host: db # ここ修正

• RAILS_ROOT/Dockerfile

FROM ruby:2.3.1
ENV LANG C.UTF-8
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
RUN gem install bundler
ENV app /app
RUN mkdir $app
WORKDIR $app
ADD Gemfile* $app/
ENV BUNDLE_GEMFILE=$app/Gemfile \
  BUNDLE_JOBS=2 \
  BUNDLE_PATH=/bundle
ADD . $app

• RAILS_ROOT/docekr-compose.yml

version: '2'
services:
  db:
    image: mysql
    environment:
      MYSQL_ROOT_PASSWORD: password
    volumes:
      - db-data:/var/lib/mysql
    ports:
      - "3306:3306"
  redis:
    image: redis
  app:
    build: .
    volumes:
      - bundle:/bundle
  web:
    extends:
      service: app
    command: /bin/sh -c "rm -f /app/tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
    volumes:
      - .:/app
    ports:
      - "3000:3000"
    links:
      - db
      - redis
  worker:
    extends:
      service: app
    command: bundle exec sidekiq
    volumes:
      - .:/app
    links:
      - db
      - redis
volumes:
  db-data:
    driver: local
  bundle:
    driver: local

https://github.com/t-taira/docker-compose-rails