README.md

Demo app for gplus gem

gplus is a complete implementation of the Google+ API for Ruby.

This repository is an example Rails 3.1 app for gplus. You can browse the source code, or clone the repository and run it locally.

Running the app locally

1. Clone this repository:

    git clone git://github.com/nfm/gplus-rails-demo.git
    cd gplus-rails-demo
   

2. Add your Google+ application's credentials to config/gplus.yml.example, and rename the file:

    # Add your API key, client ID, client secret, and redirect URI to config/gplus.yml.example
    mv config/gplus.yml.example config/gplus.yml
   

3. Migrate the database to create a users table:

    bundle exec rake db:migrate
   

4. Start WEBrick:

    rails server
   

5. Navigate to http://localhost:3000, and authorize your application for either online or offline access

6. Navigate to http://localhost:3000/users/1 and view the example data retrieved from your Google+ profile

Recreating the example application's functionality

If you have an existing application that you want to add gplus to, you can model it after this example application by completing the following steps.

You should read the gplus README for more information. You might also find the full documentation useful.

1. Add gplus to your Gemfile and run bundle install

    gem 'gplus', '~> 2.0.0'
   

2. Create a migration to add the following columns to your user model and run rake db:migrate:

    def change
      add_column :users, :token, :string
      add_column :users, :token_expires_at, :string
      add_column :users, :refresh_token, :string
    end
   

3. Define methods to initialize a Google+ API client in your ApplicationController:

    # Setup a Gplus::Client for making public (non-authorized) requests, or for requesting authorization to access a user's data
    def setup_gplus
      @gplus = Gplus::Client.new(
        :api_key => GPLUS_CONFIG['api_key'],
        :client_id => GPLUS_CONFIG['client_id'],
        :client_secret => GPLUS_CONFIG['client_secret'],
        :redirect_uri => GPLUS_CONFIG['redirect_uri']
      )
    end
   
    # Setup a Gplus::Client authorized to use the specified user's stored OAuth token
    def setup_authorized_gplus(user)
      setup_gplus
      access_token = @gplus.authorize(user.token, user.refresh_token, user.token_expires_at)
   
      # Check if the access token was implicitly refreshed
      # If it was, store the user's new token and the time that it expires at
      if @gplus.access_token_refreshed?
        user.update_attributes(:token => access_token.token, :token_expires_at => access_token.expires_at)
      end
    end
   

4. Set up a controller to handle OAuth callbacks:

    rails generate controller oauth2 callback
   
    # Add a route for it to config/routes.rb
    match 'oauth2/callback' => 'oauth2#callback'
   

5. Implement your callback action. (Use whatever method you like to get the currently logged in user, or create a new one):

    class OAuth2Controller < ApplicationController
      def callback
        setup_gplus
        access_token = @gplus_client.get_token(params[:code])
   
        # You need to find or create a user here so that you can store the access_token's attributes
   
        @user.update_attributes(
          :token => access_token.token,
          :refresh_token => access_token.refresh_token,
          :token_expires_at => access_token.expires_at
        )
      end
    end
   

6. Generate an authorization URL and link to it in a view. When a user clicks the link, they will be redirected to Google to authorize your app. After authorization, they will be redirected back to /oauth2/callback, where we're storing their OAuth token for persistent access to their data.

    # app/controllers/whatever_controller.rb
    def some_action
      setup_gplus
    end
   
    # app/views/whatever_controller/some_action.html.erb
    <%= link_to 'Authorize this app for Google+', @gplus.authorize_url %>
   
    # You'll probably want to generate an authorize_url which requests offline_access
    # so that you can access the user's Google+ profile for more than 1 hour
    <%= link_to 'Authorize this app for Google+', @gplus.authorize_url(:access_type => :offline) %>
   

7. You can now create an authorized Google+ client and make API calls:

    # app/controllers/some_other_controller.rb
    def show
      setup_authorized_gplus(current_user)
      @gplus.get_person('me')
    end