docker-composeでRails4の開発をする流れ #Rails

参考

docker-compose で Rails の開発環境を作る - Qiita

手順

./app : railsプロジェクトを準備しておく。

準備方法の例

mkdir app && cd app
rails new .
bundle install

./Dockerfile : rails用Dockerfile
./docker-compose.yml : postgresとrailsの連携

Dockerfile

FROM rails

RUN \
  unlink /etc/localtime ;\
  ln -s /usr/share/zoneinfo/Japan /etc/localtime ;\
  sed -i -e 's@http://archive@http://jp.archive@' /etc/apt/sources.list ;\
  apt-get update -qq ;\
  apt-get install -y -qq locales ;\
  locale-gen ja_JP.UTF-8 ;\
  apt-get clean
#----------------------------------------------------
WORKDIR /tmp
COPY ./app/Gemfile Gemfile
COPY ./app/Gemfile.lock Gemfile.lock
RUN bundle install

ADD ./app /app
WORKDIR /app

VOLUME /app
EXPOSE 3000

COPY と ADD が重要。

docker-compose.yml

db:
  image: postgres
  expose:
    - "5432"
web:
  build: .
  command: bundle exec rails s -p 3000 -b '0.0.0.0'
  volumes:
    - ./app:/app
  ports:
    - "3000:3000"
  links:
    - db

起動

docker-compose build
docker-compose up

起動時にエラーがでる場合

web_1 | => Booting WEBrick
web_1 | => Rails 4.2.4 application starting in development on http://0.0.0.0:3000
web_1 | => Run rails server -h for more startup options
web_1 | => Ctrl-C to shutdown server
web_1 | A server is already running. Check /app/tmp/pids/server.pid.
web_1 | Exiting
rails4_web_1 exited with code 1

プロセスが停止しているのに app/tmp/pids/server.pid が残っていることが原因。

rm -f app/tmp/pids/server.pid

index.htmlを編集してみる

app/public/index.html

hello

ルーティングの追加

現在ルーティング定義がないことを確認

$ docker-compose run web rake routes
You don't have any routes defined!

Please add some routes in config/routes.rb.

For more information about routes, see the Rails guide: http://guides.rubyonrails.org/routing.html.

config/routes.rb

 Rails.application.routes.draw do
+    resources :products do
+      member do
+        get 'short'
+        post 'toggle'
+      end
+ 
+      collection do
+        get 'sold'
+      end
+    end
 end

ルーティングが追加されたことを確認

$ docker-compose run web rake routes
        Prefix Verb   URI Pattern                    Controller#Action
 short_product GET    /products/:id/short(.:format)  products#short
toggle_product POST   /products/:id/toggle(.:format) products#toggle
 sold_products GET    /products/sold(.:format)       products#sold
      products GET    /products(.:format)            products#index
               POST   /products(.:format)            products#create
   new_product GET    /products/new(.:format)        products#new
  edit_product GET    /products/:id/edit(.:format)   products#edit
       product GET    /products/:id(.:format)        products#show
               PATCH  /products/:id(.:format)        products#update
               PUT    /products/:id(.:format)        products#update
               DELETE /products/:id(.:format)        products#destroy

小学生でもわかるRuby on Rails入門のメモ - Qiitaを実践

docker-compose run web \
rails g controller users index show

コンテナ再作成

docker-compose build
docker-compose up

http://localhost:3000/users/show にアクセスし画面が表示されることを確認。

sqlite3からpostgresqlに変更

参考:docker-compose - Docker Compose - クイックスタート・ガイド：Compose と Rails - Qiita

Gemfile

+ gem 'pg'

config/database.yml

default: &default
  adapter: postgresql
  encoding: unicode
  pool: 5
  username: postgres
  password:
  host: db

development:
  <<: *default
  database: sample_app_development

test:
  <<: *default
  database: sample_app_test

production:
  <<: *default
  database: sample_app_production

コンテナ再作成

docker-compose build
docker-compose run web rake db:create
docker-compose up

DBの作成のため初回のみdocker-compose run web rake db:createが必要。

modelの作成

user.{name,username,location,about}カラム作成

docker-compose run web \
rails g model user name:string username:string location:string about:text

コンテナ再作成

docker-compose build
docker-compose run web rake db:migrate
docker-compose up

初期データの投入

db/seeds.rb

@user = User.new
@user.name = 'Ryo Suzuki'
@user.username = 'ryooopan'
@user.location = 'Kanagawa, Japan'
@user.about = 'Hello, I am Ryo. I am from database!'
@user.save

@user = User.new
@user.name = 'Shohei Aoki'
@user.username = 'moyahima'
@user.location = 'Tottori, Japan'
@user.about = 'Nice to meet you. I am from database!'
@user.save

初期データの投入

docker-compose run web \
rake db:seed

config/routes.rb

Rails.application.routes.draw do
  get "users/index"
  get 'users/show'
+ get "users/show/:username" => "users#show"

cd app
mkdir -p app/views/users
mkdir app/controllers

app/views/users/show.html.erb

<h1><%= @user[:name] %></h1>
<p><%= @user[:username] %></p>
<ul>
  <li>Location : <%= @user[:location] %></li>
  <li>About    : <%= @user[:about] %></li>
</ul>

app/controllers/users_controller.rb

class UsersController < ApplicationController
  def index
  end

  def show
    @user = User.find_by(:username => params[:username])
  end
end

http://localhost:3000/users/show/ryooopan にアクセスし以下表示を確認