Add mentions send email notifications worker (#5549)

* Added email notification worker for mentions
  * Modified the email generation to after_create_commit
  * Modified Mention model to use the new worker
  * Added tests for the worker

app/models/mention.rb

@@ -9,7 +9,7 @@ class Mention < ApplicationRecord
   validates :mentionable_type, presence: true
   validate :permission
 
-  after_create :send_email_notification
+  after_create_commit :send_email_notification
 
   def self.create_all(notifiable)
     Mentions::CreateAllWorker.perform_async(notifiable.id, notifiable.class.name)
@@ -21,7 +21,7 @@ class Mention < ApplicationRecord
     user = User.find(user_id)
     return unless user.email.present? && user.email_mention_notifications
 
-    Mentions::SendEmailNotificationJob.perform_later(id)
+    Mentions::SendEmailNotificationWorker.perform_async(id)
   end
 
   def permission

app/workers/mentions/send_email_notification_worker.rb

@@ -0,0 +1,11 @@
+module Mentions
+  class SendEmailNotificationWorker
+    include Sidekiq::Worker
+    sidekiq_options queue: :default, retry: 10
+
+    def perform(mention_id)
+      mention = Mention.find_by(id: mention_id)
+      NotifyMailer.new_mention_email(mention) if mention
+    end
+  end
+end

spec/workers/mentions/send_email_notification_worker_spec.rb

@@ -0,0 +1,32 @@
+require "rails_helper"
+
+RSpec.describe Mentions::SendEmailNotificationWorker, type: :worker do
+  include_examples "#enqueues_on_correct_queue", "default", 1
+
+  describe "#perform" do
+    let(:worker) { subject }
+    let(:user) { create(:user) }
+    let(:mention) { create(:mention, user_id: user.id, mentionable_id: comment.id, mentionable_type: "Comment") }
+    let(:comment) { create(:comment, user_id: user.id, commentable: create(:article)) }
+
+    context "with mention" do
+      it "calls on NotifyMailer" do
+        worker.perform(mention.id) do
+          expect(NotifyMailer).to have_received(:new_mention_email).with(mention)
+        end
+      end
+    end
+
+    context "without a mention" do
+      it "does not error" do
+        expect { worker.perform(nil) }.not_to raise_error
+      end
+
+      it "does not call NotifyMailer" do
+        worker.perform(nil) do
+          expect(NotifyMailer).not_to have_received(:new_mention_email)
+        end
+      end
+    end
+  end
+end