Chore: Remove dead code related to billing (#935)

- remove subscription model
- remove billing-related code

app/controllers/api/base_controller.rb

@@ -10,8 +10,4 @@ class Api::BaseController < ApplicationController
   def authenticate_by_access_token?
     request.headers[:api_access_token].present? || request.headers[:HTTP_API_ACCESS_TOKEN].present?
   end
-
-  def check_billing_enabled
-    raise ActionController::RoutingError, 'Not Found' unless ENV['BILLING_ENABLED']
-  end
 end

app/controllers/api/v1/accounts/subscriptions_controller.rb

@@ -1,13 +0,0 @@
-class Api::V1::Accounts::SubscriptionsController < Api::V1::Accounts::BaseController
-  skip_before_action :check_subscription
-
-  before_action :check_billing_enabled
-
-  def index
-    render json: Current.account.subscription_data
-  end
-
-  def status
-    render json: Current.account.subscription.summary
-  end
-end

app/controllers/api/v1/accounts_controller.rb

@@ -2,7 +2,7 @@ class Api::V1::AccountsController < Api::BaseController
   include AuthHelper
 
   skip_before_action :verify_authenticity_token, only: [:create]
-  skip_before_action :authenticate_user!, :set_current_user, :check_subscription, :handle_with_exception,
+  skip_before_action :authenticate_user!, :set_current_user, :handle_with_exception,
                      only: [:create], raise: false
   before_action :check_signup_enabled, only: [:create]
   before_action :fetch_account, except: [:create]

app/controllers/api/v1/agent_bots_controller.rb

@@ -1,6 +1,5 @@
 class Api::V1::AgentBotsController < Api::BaseController
   skip_before_action :authenticate_user!
-  skip_before_action :check_subscription
 
   def index
     render json: AgentBot.all

app/controllers/api/v1/webhooks_controller.rb

@@ -1,18 +1,6 @@
 class Api::V1::WebhooksController < ApplicationController
   skip_before_action :authenticate_user!, raise: false
   skip_before_action :set_current_user
-  skip_before_action :check_subscription
-
-  before_action :login_from_basic_auth, only: [:chargebee]
-  before_action :check_billing_enabled, only: [:chargebee]
-
-  def chargebee
-    chargebee_consumer.consume
-    head :ok
-  rescue StandardError => e
-    Raven.capture_exception(e)
-    head :ok
-  end
 
   def twitter_crc
     render json: { response_token: "sha256=#{twitter_client.generate_crc(params[:crc_token])}" }
@@ -34,16 +22,6 @@ class Api::V1::WebhooksController < ApplicationController
     end
   end
 
-  def login_from_basic_auth
-    authenticate_or_request_with_http_basic do |username, password|
-      username == ENV['CHARGEBEE_WEBHOOK_USERNAME'] && password == ENV['CHARGEBEE_WEBHOOK_PASSWORD']
-    end
-  end
-
-  def chargebee_consumer
-    @chargebee_consumer ||= ::Webhooks::Chargebee.new(params)
-  end
-
   def twitter_consumer
     @twitter_consumer ||= ::Webhooks::Twitter.new(params)
   end