1 files changed, 84 insertions, 33 deletions

diff --git a/app/services/notification_service.rb b/app/services/notification_service.rb
index d7d2cde1004..636cfbf5b45 100644
--- a/app/services/notification_service.rb
+++ b/app/services/notification_service.rb
@@ -7,7 +7,32 @@
 # Ex.
 #   NotificationService.new.new_issue(issue, current_user)
 #
+# When calculating the recipients of a notification is expensive (for instance,
+# in the new issue case), `#async` will make that calculation happen in Sidekiq
+# instead:
+#
+#   NotificationService.new.async.new_issue(issue, current_user)
+#
 class NotificationService
+  class Async
+    attr_reader :parent
+    delegate :respond_to_missing, to: :parent
+
+    def initialize(parent)
+      @parent = parent
+    end
+
+    def method_missing(meth, *args)
+      return super unless parent.respond_to?(meth)
+
+      MailScheduler::NotificationServiceWorker.perform_async(meth.to_s, *args)
+    end
+  end
+
+  def async
+    @async ||= Async.new(self)
+  end
+
   # Always notify user about ssh key added
   # only if ssh key is not deploy key
   #
@@ -104,6 +129,7 @@ class NotificationService
 
   # When create a merge request we should send an email to:
   #
+  #  * mr author
   #  * mr assignee if their notification level is not Disabled
   #  * project team members with notification level higher then Participating
   #  * watchers of the mr's labels
@@ -113,6 +139,25 @@ class NotificationService
     new_resource_email(merge_request, :new_merge_request_email)
   end
 
+  def push_to_merge_request(merge_request, current_user, new_commits: [], existing_commits: [])
+    new_commits = new_commits.map { |c| { short_id: c.short_id, title: c.title } }
+    existing_commits = existing_commits.map { |c| { short_id: c.short_id, title: c.title } }
+    recipients = NotificationRecipientService.build_recipients(merge_request, current_user, action: "push_to")
+
+    recipients.each do |recipient|
+      mailer.send(:push_to_merge_request_email, recipient.user.id, merge_request.id, current_user.id, recipient.reason, new_commits: new_commits, existing_commits: existing_commits).deliver_later
+    end
+  end
+
+  # When a merge request is found to be unmergeable, we should send an email to:
+  #
+  #  * mr author
+  #  * mr merge user if set
+  #
+  def merge_request_unmergeable(merge_request)
+    merge_request_unmergeable_email(merge_request)
+  end
+
   # When merge request text is updated, we should send an email to:
   #
   #  * newly mentioned project team members with notification level higher than Participating
@@ -132,8 +177,23 @@ class NotificationService
   #  * merge_request assignee if their notification level is not Disabled
   #  * users with custom level checked with "reassign merge request"
   #
-  def reassigned_merge_request(merge_request, current_user)
-    reassign_resource_email(merge_request, current_user, :reassigned_merge_request_email)
+  def reassigned_merge_request(merge_request, current_user, previous_assignee)
+    recipients = NotificationRecipientService.build_recipients(
+      merge_request,
+      current_user,
+      action: "reassign",
+      previous_assignee: previous_assignee
+    )
+
+    recipients.each do |recipient|
+      mailer.reassigned_merge_request_email(
+        recipient.user.id,
+        merge_request.id,
+        previous_assignee&.id,
+        current_user.id,
+        recipient.reason
+      ).deliver_later
+    end
   end
 
   # When we add labels to a merge request we should send an email to:
@@ -363,6 +423,20 @@ class NotificationService
     end
   end
 
+  def issue_due(issue)
+    recipients = NotificationRecipientService.build_recipients(
+      issue,
+      issue.author,
+      action: 'due',
+      custom_action: :issue_due,
+      skip_current_user: false
+    )
+
+    recipients.each do |recipient|
+      mailer.send(:issue_due_email, recipient.user.id, issue.id, recipient.reason).deliver_later
+    end
+  end
+
   protected
 
   def new_resource_email(target, method)
@@ -397,29 +471,6 @@ class NotificationService
     end
   end
 
-  def reassign_resource_email(target, current_user, method)
-    previous_assignee_id = previous_record(target, 'assignee_id')
-    previous_assignee = User.find_by(id: previous_assignee_id) if previous_assignee_id
-
-    recipients = NotificationRecipientService.build_recipients(
-      target,
-      current_user,
-      action: "reassign",
-      previous_assignee: previous_assignee
-    )
-
-    recipients.each do |recipient|
-      mailer.send(
-        method,
-        recipient.user.id,
-        target.id,
-        previous_assignee_id,
-        current_user.id,
-        recipient.reason
-      ).deliver_later
-    end
-  end
-
   def relabeled_resource_email(target, labels, current_user, method)
     recipients = labels.flat_map { |l| l.subscribers(target.project) }.uniq
     recipients = notifiable_users(
@@ -443,18 +494,18 @@ class NotificationService
     end
   end
 
-  def mailer
-    Notify
-  end
-
-  def previous_record(object, attribute)
-    return unless object && attribute
+  def merge_request_unmergeable_email(merge_request)
+    recipients = NotificationRecipientService.build_merge_request_unmergeable_recipients(merge_request)
 
-    if object.previous_changes.include?(attribute)
-      object.previous_changes[attribute].first
+    recipients.each do |recipient|
+      mailer.merge_request_unmergeable_email(recipient.user.id, merge_request.id).deliver_later
     end
   end
 
+  def mailer
+    Notify
+  end
+
   private
 
   def recipients_for_pages_domain(domain)