www.redmine.orgのPlugin Turorial を和訳してみます。

プラグイン チュートリアル¶

注意: このチュートリアルはRedmineの開発リビジョン r1786 以上を対象にしています。

• Table of contents
• プラグイン チュートリアル
  • 新しいプラグインを作る。
  • モデルを作る
  • コントローラを作成する。
  • Extending menus
    • Extending the application menu
    • Extending the project menu
  • Adding new permissions
  • Creating a project module
  • Improving the plugin views
    • Adding stylesheets
    • Setting page title

新しいプラグインを作る。¶

プラグインの新規作成はRedmineのプラグインジェネレータを使用して行うことができます。
ジェネレータのコマンドは以下です。:

ruby script/generate redmine_plugin <plugin_name>

コマンドプロンプトを開き "cd" であなたがredmineをインストールしたディレクトリに移動し、以下のコマンドを実行してみましょう。:

% ruby script/generate redmine_plugin Polls

vendor/plugins/redmine_polls の下に以下のようなファイルとディレクトリが作られます:

      create  vendor/plugins/redmine_polls/app/controllers
      create  vendor/plugins/redmine_polls/app/helpers
      create  vendor/plugins/redmine_polls/app/models
      create  vendor/plugins/redmine_polls/app/views
      create  vendor/plugins/redmine_polls/db/migrate
      create  vendor/plugins/redmine_polls/lib/tasks
      create  vendor/plugins/redmine_polls/assets/images
      create  vendor/plugins/redmine_polls/assets/javascripts
      create  vendor/plugins/redmine_polls/assets/stylesheets
      create  vendor/plugins/redmine_polls/lang
      create  vendor/plugins/redmine_polls/README
      create  vendor/plugins/redmine_polls/init.rb
      create  vendor/plugins/redmine_polls/lang/en.yml

vendor/plugins/redmine_polls/init.rb を編集してあなたのプラグインの情報を書き込んでください。(name, author, description および version):

require 'redmine'

Redmine::Plugin.register :redmine_polls do
  name 'Polls plugin'
  author 'John Smith'
  description 'A plugin for managing polls'
  version '0.0.1'
end

そしてRedmineを起動し、ブラウザから次のアドレスを入力します。http://localhost:3000/admin/info.
ログイン後、あなたのプラグインがプラグイン一覧に加わっていることが確認できます。

モデルを作る¶

それではこのプラグインのモデルとして Poll を作ってみましょう。:

ruby script/generate redmine_plugin_model polls poll question:string yes:integer no:integer

このコマンドで Poll モデルおよびPollモデルに対応したマイグレーションファイルが作成されます。
(訳注:マイグレーションファイルとは、RedmineのDBにこのモデル用のテーブルを作成するためのスクリプトファイルです)

ここで注意が必要です。timestamped migrationは今のRedmineプラグインエンジンではサポートされていません。ファイル名についているタイムスタンプを"001", "002"のような名前に変更してください。

実際にデータベースへのマイグレーションを行うためには以下のコマンドを実行します。:

rake db:migrate_plugins

すべてのプラグインはそれぞれに自身のマイグレーションファイルを持っています。

それではconsoleスクリプトからPollのデータを追加してみましょう。ちゃんとテーブルが作られていることを確認できます。consoleを使用すると対話的にRedmineを動かして確認できます。また、遊びながらいろいろな情報を得ることができます。それでは2つのPollオブジェクトを作ります。

script/console
>> Poll.create(:question => "Can you see this poll ?")
>> Poll.create(:question => "And can you see this other poll ?")
>> exit

プラグインディレクトリの vendor/plugins/redmine_polls/app/models/poll.rb を編集して #vote メソッドを追加しましょう。このメソッドはコントローラから実行されるものです。:

class Poll < ActiveRecord::Base
  def vote(answer)
    increment(answer == 'yes' ? :yes : :no)
  end
end

コントローラを作成する。¶

この段階ではまだこのプラグインは何もすることができません。このプラグインにコントローラを追加してみましょう。コントローラの作成にはプラグインコントローラジェネレータを使用できます。文法は以下です。:

ruby script/generate redmine_plugin_controller <plugin_name> <controller_name> [<actions>]

ではコマンドプロンプトから以下のように打ってみましょう。:

% ruby script/generate redmine_plugin_controller Polls polls index vote
      exists  app/controllers/
      exists  app/helpers/
      create  app/views/polls
      create  test/functional/
      create  app/controllers/polls_controller.rb
      create  test/functional/polls_controller_test.rb
      create  app/helpers/polls_helper.rb
      create  app/views/polls/index.html.erb
      create  app/views/polls/vote.html.erb

コントローラ PollsController と2つのアクション (#index and #vote) が作成されます。

vendor/plugins/redmine_polls/app/controllers/polls_controller.rb を編集して 2つのアクションを実装します。

class PollsController < ApplicationController
  unloadable

  def index
    @polls = Poll.find(:all)
  end

  def vote
    poll = Poll.find(params[:id])
    poll.vote(params[:answer])
    if poll.save
      flash[:notice] = 'Vote saved.'
      redirect_to :action => 'index'
    end
  end
end

そしてvendor/plugins/redmine_polls/app/views/polls/index.html.erb を編集すると先ほど作成した２つのpollを表示できます。:

<h2>Polls</h2>

<% @polls.each do |poll| %>
  <p>
  <%= poll[:question] %>?
  <%= link_to 'Yes', {:action => 'vote', :id => poll[:id], :answer => 'yes'}, :method => :post %> (<%= poll[:yes] %>) /
  <%= link_to 'No', {:action => 'vote', :id => poll[:id], :answer => 'no'}, :method => :post %> (<%= poll[:no] %>)
  </p>
<% end %>

You can remove vendor/plugins/redmine_polls/app/views/polls/vote.html.erb since no rendering is done by the corresponding action.

Now, restart the application and point your browser to http://localhost:3000/polls.
You should see the 2 polls and you should be able to vote for them:

Note that poll results are reset on each request if you don't run the application in production mode, since our poll "model" is stored in a class variable in this example.

Extending menus¶

Our controller works fine but users have to know the url to see the polls. Using the Redmine plugin API, you can extend standard menus.
So let's add a new item to the application menu.

Extending the application menu¶

Edit vendor/plugins/redmine_polls/init.rb at the root of your plugin directory to add the following line at the end of the plugin registration block:

Redmine::Plugin.register :redmine_polls do
  [...]

  menu :application_menu, :polls, { :controller => 'polls', :action => 'index' }, :caption => 'Polls'
end

Syntax is:

menu(menu_name, item_name, url, options={})

There are 4 menus that you can extend:

• :top_menu - the top left menu
• :account_menu - the top right menu with sign in/sign out links
• :application_menu - the main menu displayed when the user is not inside a project
• :project_menu - the main menu displayed when the user is inside a project

Available options are:

• :param - the parameter key that is used for the project id (default is :id)
• :if - a Proc that is called before rendering the item, the item is displayed only if it returns true
• :caption - the menu caption that can be:
  • a localized string Symbol
  • a String
  • a Proc that can take the project as argument

• :before, :after - specify where the menu item should be inserted (eg. :after => :activity)
• :last - if set to true, the item will stay at the end of the menu (eg. :last => true)
• :html_options - a hash of html options that are passed to link_to when rendering the menu item

In our example, we've added an item to the application menu which is emtpy by default.
Restart the application and go to http://localhost:3000:

Now you can access the polls by clicking the Polls tab from the welcome screen.

Extending the project menu¶

Now, let's consider that the polls are defined at project level (even if it's not the case in our example poll model). So we would like to add the Polls tab to the project menu instead.
Open init.rb and replace the line that was added just before with these 2 lines:

Redmine::Plugin.register :redmine_polls do
  [...]

  permission :polls, {:polls => [:index, :vote]}, :public => true
  menu :project_menu, :polls, { :controller => 'polls', :action => 'index' }, :caption => 'Polls', :after => :activity, :param => :project_id
end

The second line adds our Polls tab to the project menu, just after the activity tab.
The first line is required and declares that our 2 actions from PollsController are public. We'll come back later to explain this with more details.

Restart the application again and go to one of your projects:

If you click the Polls tab, you should notice that the project menu is no longer displayed.
To make the project menu visible, you have to initialize the controller's instance variable @project.

Edit your PollsController to do so:

def index
  @project = Project.find(params[:project_id])
  @polls = Poll.find(:all) # @project.polls
end

The project id is available in the :project_id param because of the :param => :project_id option in the menu item declaration above.

Now, you should see the project menu when viewing the polls:

Adding new permissions¶

For now, anyone can vote for polls. Let's make it more configurable by changing the permission declaration.
We're going to declare 2 project based permissions, one for viewing the polls and an other one for voting. These permissions are no longer public (:public => true option is removed).

Edit vendor/plugins/redmine_polls/init.rb to replace the previous permission declaration with these 2 lines:

  permission :view_polls, :polls => :index
  permission :vote_polls, :polls => :vote

Restart the application and go to http://localhost:3000/roles/report:

You're now able to give these permissions to your existing roles.

Of course, some code needs to be added to the PollsController so that actions are actually protected according to the permissions of the current user.
For this, we just need to append the :authorize filter and make sure that the @project instance variable is properly set before calling this filter.

Here is how it would look like for the #index action:

class PollsController < ApplicationController
  unloadable

  before_filter :find_project, :authorize, :only => :index

  [...]

  def index
    @polls = Poll.find(:all) # @project.polls
  end

  [...]

  private

  def find_project
    # @project variable must be set before calling the authorize filter
    @project = Project.find(params[:project_id])
  end
end

Retrieving the current project before the #vote action could be done using a similar way.
After this, viewing and voting polls will be only available to admin users or users that have the appropriate role on the project.

Creating a project module¶

For now, the poll functionality is added to all your projects. But you way want to enable polls for some projects only.
So, let's create a 'Polls' project module. This is done by wrapping the permissions declaration inside a call to #project_module.

Edit init.rb and change the permissions declaration:

  project_module :polls do
    permission :view_polls, :polls => :index
    permission :vote_polls, :polls => :vote
  end

Restart the application and go to one of your project settings.
Click on the Modules tab. You should see the Polls module at the end of the modules list (disabled by default):

You can now enable/disable polls at project level.

Improving the plugin views¶

Adding stylesheets¶

Let's start by adding a stylesheet to our plugin views.
Create a file named voting.css in the vendor/plugins/redmine_polls/assets/stylesheets directory:

a.vote { font-size: 120%; }
a.vote.yes { color: green; }
a.vote.no  { color: red; }

When starting the application, plugin assets are automatically copied to public/plugin_assets/redmine_polls/ by Rails Engines to make them available through your web server. So any change to your plugin stylesheets or javascripts needs an application restart.

Then, append the following lines at the end of vendor/plugins/redmine_polls/app/views/polls/index.html.erb so that your stylesheet get included in the page header by Redmine:

<% content_for :header_tags do %>
    <%= stylesheet_link_tag 'voting', :plugin => 'redmine_polls' %>
<% end %>

Note that the :plugin => 'redmine_polls' option is required when calling the stylesheet_link_tag helper.

Javascripts can be included in plugin views using the javascript_include_tag helper in the same way.

Setting page title¶

You can set the HTML title from inside your views by using the html_title helper.
Example:

<% html_title "Polls" -%>