Rails5でdeviseを実装

#概要
Rails5でdeviseを実装した時の自分的なメモ。

#手順
Gemfileにdeviseを記述する。

```
Gemfile

gem 'devise'
```

deviseをインストール！！！

```
$ bundle install
```

下記のコメントが出るので順番に設定していく。

```
      create  config/initializers/devise.rb
      create  config/locales/devise.en.yml
===============================================================================

Some setup you must do manually if you haven't yet:

  1. Ensure you have defined default url options in your environments files. Here
     is an example of default_url_options appropriate for a development environment
     in config/environments/development.rb:

       config.action_mailer.default_url_options = { host: 'localhost', port: 3000 }

     In production, :host should be set to the actual host of your application.

  2. Ensure you have defined root_url to *something* in your config/routes.rb.
     For example:

       root to: "home#index"

  3. Ensure you have flash messages in app/views/layouts/application.html.erb.
     For example:

       <p class="notice"><%= notice %></p>
       <p class="alert"><%= alert %></p>

  4. You can copy Devise views (for customization) to your app by running:

       rails g devise:views

===============================================================================
```

メーラーの開発環境URLの設定

```
config/environments/development.rb:

config.action_mailer.default_url_options = { host: 'localhost', port: 3000 }
```

ルーティングを設定

```
routes.rb

Rails.application.routes.draw do
	root 'top#index'
end
```

共通テンプレートにnoticeとalertを追加。

```
application.html.erb

<!DOCTYPE html>
<html>
  <head>
    <title>Timekeeper</title>
    <%= csrf_meta_tags %>

    <%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track': 'reload' %>
    <%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %>
  </head>

  <body>

  	<p class="notice"><%= notice %></p>
    <p class="alert"><%= alert %></p>

    <%= yield %>
  </body>
</html>
```

devise用のviewsを作成。

```
$ rails g devise:views
Running via Spring preloader in process 2834
Expected boolean default value for '--markerb'; got :erb (string)
      invoke  Devise::Generators::SharedViewsGenerator
      create    app/views/devise/shared
      create    app/views/devise/shared/_links.html.erb
      invoke  form_for
      create    app/views/devise/confirmations
      create    app/views/devise/confirmations/new.html.erb
      create    app/views/devise/passwords
      create    app/views/devise/passwords/edit.html.erb
      create    app/views/devise/passwords/new.html.erb
      create    app/views/devise/registrations
      create    app/views/devise/registrations/edit.html.erb
      create    app/views/devise/registrations/new.html.erb
      create    app/views/devise/sessions
      create    app/views/devise/sessions/new.html.erb
      create    app/views/devise/unlocks
      create    app/views/devise/unlocks/new.html.erb
      invoke  erb
      create    app/views/devise/mailer
      create    app/views/devise/mailer/confirmation_instructions.html.erb
      create    app/views/devise/mailer/email_changed.html.erb
      create    app/views/devise/mailer/password_change.html.erb
      create    app/views/devise/mailer/reset_password_instructions.html.erb
      create    app/views/devise/mailer/unlock_instructions.html.erb
```

migrateを実行して、DBに反映する。

```
$ bundle exec rake db:migrate
```

ログインしてないと認証画面に飛ぶように設定。

```
app/controllers/application_controller.rb

before_action :authenticate_admin!
```