Feature: SignIn with Twitter (#479)

* Add Twitter SignIn flow

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/controllers/twitter/authorizations_controller.rb

@@ -0,0 +1,30 @@
+class Twitter::AuthorizationsController < Twitter::BaseController
+  def create
+    @response = twitter_client.request_oauth_token(url: twitter_callback_url)
+
+    if @response.status == '200'
+      ::Redis::Alfred.setex(oauth_token, account.id)
+      redirect_to oauth_authorize_endpoint(oauth_token)
+    else
+      redirect_to app_new_twitter_inbox_url
+    end
+  end
+
+  private
+
+  def oauth_token
+    parsed_body['oauth_token']
+  end
+
+  def user
+    @user ||= User.find_by(id: params[:user_id])
+  end
+
+  def account
+    @account ||= user.account
+  end
+
+  def oauth_authorize_endpoint(oauth_token)
+    "#{twitter_api_base_url}/oauth/authorize?oauth_token=#{oauth_token}"
+  end
+end

app/controllers/twitter/base_controller.rb

@@ -0,0 +1,24 @@
+class Twitter::BaseController < ApplicationController
+  private
+
+  def parsed_body
+    @parsed_body ||= Rack::Utils.parse_nested_query(@response.raw_response.body)
+  end
+
+  def host
+    ENV.fetch('FRONTEND_URL', '')
+  end
+
+  def twitter_client
+    Twitty::Facade.new do |config|
+      config.consumer_key = ENV.fetch('TWITTER_CONSUMER_KEY', nil)
+      config.consumer_secret = ENV.fetch('TWITTER_CONSUMER_SECRET', nil)
+      config.base_url = twitter_api_base_url
+      config.environment = ENV.fetch('TWITTER_ENVIRONMENT', '')
+    end
+  end
+
+  def twitter_api_base_url
+    'https://api.twitter.com'
+  end
+end

app/controllers/twitter/callbacks_controller.rb

@@ -0,0 +1,51 @@
+class Twitter::CallbacksController < Twitter::BaseController
+  def show
+    @response = twitter_client.access_token(
+      oauth_token: permitted_params[:oauth_token],
+      oauth_verifier: permitted_params[:oauth_verifier]
+    )
+    if @response.status == '200'
+      inbox = build_inbox
+      ::Redis::Alfred.delete(permitted_params[:oauth_token])
+      ::Twitter::WebhookSubscribeService.new(inbox_id: inbox.id).perform
+      redirect_to app_twitter_inbox_agents_url(inbox_id: inbox.id)
+    else
+      redirect_to app_new_twitter_inbox_url
+    end
+  end
+
+  private
+
+  def parsed_body
+    @parsed_body ||= Rack::Utils.parse_nested_query(@response.raw_response.body)
+  end
+
+  def account_id
+    ::Redis::Alfred.get(permitted_params[:oauth_token])
+  end
+
+  def account
+    @account ||= Account.find_by!(id: account_id)
+  end
+
+  def build_inbox
+    ActiveRecord::Base.transaction do
+      twitter_profile = account.twitter_profiles.create(
+        twitter_access_token: parsed_body['oauth_token'],
+        twitter_access_token_secret: parsed_body['oauth_token_secret'],
+        profile_id: parsed_body['user_id'],
+        name: parsed_body['screen_name']
+      )
+      account.inboxes.create(
+        name: parsed_body['screen_name'],
+        channel: twitter_profile
+      )
+    rescue StandardError => e
+      Rails.logger e
+    end
+  end
+
+  def permitted_params
+    params.permit(:oauth_token, :oauth_verifier)
+  end
+end