Notify Bugsnag on sign-up errors

This may lead to more error reports than we want to see. A not existing
email address may cause Bugsnag to be notified. If this happens, we can
rescue form these specific errors and only report the rest.

app/controllers/user_registrations_controller.rb

@@ -1,3 +1,5 @@
+require 'open_food_network/error_logger'
+
 class UserRegistrationsController < Spree::UserRegistrationsController
   before_filter :set_checkout_redirect, only: :create
 
@@ -21,7 +23,8 @@ class UserRegistrationsController < Spree::UserRegistrationsController
     else
       render_error(@user.errors)
     end
-  rescue StandardError
+  rescue StandardError => error
+    OpenFoodNetwork::ErrorLogger.notify(error)
     render_error(message: I18n.t('devise.user_registrations.spree_user.unknown_error'))
   end
 

lib/open_food_network/error_logger.rb

@@ -0,0 +1,13 @@
+# Our error logging API currently wraps Bugsnag.
+# It makes us more flexible if we wanted to replace Bugsnag or change logging
+# behaviour.
+module OpenFoodNetwork
+  module ErrorLogger
+    # Tries to escalate the error to a developer.
+    # If Bugsnag is configured, it will notify it. It would be nice to implement
+    # some kind of fallback.
+    def self.notify(error)
+      Bugsnag.notify(error)
+    end
+  end
+end

spec/controllers/user_registrations_controller_spec.rb

@@ -31,6 +31,7 @@ describe UserRegistrationsController, type: :controller do
 
     it "returns error when emailing fails" do
       allow(Spree::UserMailer).to receive(:confirmation_instructions).and_raise("Some error")
+      expect(OpenFoodNetwork::ErrorLogger).to receive(:notify)
 
       xhr :post, :create, spree_user: user_params, use_route: :spree
 

spec/lib/open_food_network/error_logger_spec.rb

@@ -0,0 +1,14 @@
+require 'spec_helper'
+require 'open_food_network/error_logger'
+
+module OpenFoodNetwork
+  describe ErrorLogger do
+    let(:error) { StandardError.new("Test") }
+
+    it "notifies Bugsnag" do
+      expect(Bugsnag).to receive(:notify).with(error)
+
+      ErrorLogger.notify(error)
+    end
+  end
+end