Send notifications to group-specific email address

- Select notification email by walking up group/subgroup path
- Add settings UI to set group email notification address
- Add tests

8 files changed, 37 insertions, 19 deletions

diff --git a/app/mailers/emails/issues.rb b/app/mailers/emails/issues.rb
index 2b046d17122..f3a3203f7ad 100644
--- a/app/mailers/emails/issues.rb
+++ b/app/mailers/emails/issues.rb
@@ -83,7 +83,7 @@ module Emails
       @project = Project.find(project_id)
       @results = results
 
-      mail(to: @user.notification_email, subject: subject('Imported issues')) do |format|
+      mail(to: recipient(@user.id, @project.group), subject: subject('Imported issues')) do |format|
         format.html { render layout: 'mailer' }
         format.text { render layout: 'mailer' }
       end
@@ -103,7 +103,7 @@ module Emails
     def issue_thread_options(sender_id, recipient_id, reason)
       {
         from: sender(sender_id),
-        to: recipient(recipient_id),
+        to: recipient(recipient_id, @project.group),
         subject: subject("#{@issue.title} (##{@issue.iid})"),
         'X-GitLab-NotificationReason' => reason
       }
diff --git a/app/mailers/emails/members.rb b/app/mailers/emails/members.rb
index 91dfdf58982..8225215ae4d 100644
--- a/app/mailers/emails/members.rb
+++ b/app/mailers/emails/members.rb
@@ -58,9 +58,8 @@ module Emails
       @member_source_type = member_source_type
       @member_source = member_source_class.find(source_id)
       @invite_email = invite_email
-      inviter = User.find(created_by_id)
 
-      mail(to: inviter.notification_email,
+      mail(to: recipient(created_by_id, member_source_type == 'project' ? @member_source.group : @member_source),
            subject: subject('Invitation declined'))
     end
 
diff --git a/app/mailers/emails/merge_requests.rb b/app/mailers/emails/merge_requests.rb
index fc6ed695675..864f9e2975a 100644
--- a/app/mailers/emails/merge_requests.rb
+++ b/app/mailers/emails/merge_requests.rb
@@ -110,7 +110,7 @@ module Emails
     def merge_request_thread_options(sender_id, recipient_id, reason = nil)
       {
         from: sender(sender_id),
-        to: recipient(recipient_id),
+        to: recipient(recipient_id, @project.group),
         subject: subject("#{@merge_request.title} (#{@merge_request.to_reference})"),
         'X-GitLab-NotificationReason' => reason
       }
diff --git a/app/mailers/emails/notes.rb b/app/mailers/emails/notes.rb
index 1b3c1f9a8a9..70d296fe3b8 100644
--- a/app/mailers/emails/notes.rb
+++ b/app/mailers/emails/notes.rb
@@ -51,7 +51,7 @@ module Emails
     def note_thread_options(recipient_id)
       {
         from: sender(@note.author_id),
-        to: recipient(recipient_id),
+        to: recipient(recipient_id, @group),
         subject: subject("#{@note.noteable.title} (#{@note.noteable.reference_link_text})")
       }
     end
diff --git a/app/mailers/emails/pages_domains.rb b/app/mailers/emails/pages_domains.rb
index ce449237ef6..2d390666f65 100644
--- a/app/mailers/emails/pages_domains.rb
+++ b/app/mailers/emails/pages_domains.rb
@@ -7,7 +7,7 @@ module Emails
       @project = domain.project
 
       mail(
-        to: recipient.notification_email,
+        to: recipient(recipient.id, @project.group),
         subject: subject("GitLab Pages domain '#{domain.domain}' has been enabled")
       )
     end
@@ -17,7 +17,7 @@ module Emails
       @project = domain.project
 
       mail(
-        to: recipient.notification_email,
+        to: recipient(recipient.id, @project.group),
         subject: subject("GitLab Pages domain '#{domain.domain}' has been disabled")
       )
     end
@@ -27,7 +27,7 @@ module Emails
       @project = domain.project
 
       mail(
-        to: recipient.notification_email,
+        to: recipient(recipient.id, @project.group),
         subject: subject("Verification succeeded for GitLab Pages domain '#{domain.domain}'")
       )
     end
@@ -37,7 +37,7 @@ module Emails
       @project = domain.project
 
       mail(
-        to: recipient.notification_email,
+        to: recipient(recipient.id, @project.group),
         subject: subject("ACTION REQUIRED: Verification failed for GitLab Pages domain '#{domain.domain}'")
       )
     end
diff --git a/app/mailers/emails/projects.rb b/app/mailers/emails/projects.rb
index 2500622caa7..f81f76f67f7 100644
--- a/app/mailers/emails/projects.rb
+++ b/app/mailers/emails/projects.rb
@@ -7,20 +7,20 @@ module Emails
       @project = Project.find project_id
       @target_url = project_url(@project)
       @old_path_with_namespace = old_path_with_namespace
-      mail(to: @user.notification_email,
+      mail(to: recipient(user_id, @project.group),
            subject: subject("Project was moved"))
     end
 
     def project_was_exported_email(current_user, project)
       @project = project
-      mail(to: current_user.notification_email,
+      mail(to: recipient(current_user.id, project.group),
            subject: subject("Project was exported"))
     end
 
     def project_was_not_exported_email(current_user, project, errors)
       @project = project
       @errors = errors
-      mail(to: current_user.notification_email,
+      mail(to: recipient(current_user.id, @project.group),
            subject: subject("Project export error"))
     end
 
@@ -28,7 +28,7 @@ module Emails
       @project = project
       @user = user
 
-      mail(to: user.notification_email, subject: subject("Project cleanup has completed"))
+      mail(to: recipient(user.id, project.group), subject: subject("Project cleanup has completed"))
     end
 
     def repository_cleanup_failure_email(project, user, error)
@@ -36,7 +36,7 @@ module Emails
       @user = user
       @error = error
 
-      mail(to: user.notification_email, subject: subject("Project cleanup failure"))
+      mail(to: recipient(user.id, project.group), subject: subject("Project cleanup failure"))
     end
 
     def repository_push_email(project_id, opts = {})
diff --git a/app/mailers/emails/remote_mirrors.rb b/app/mailers/emails/remote_mirrors.rb
index 2018eb7260b..2d8137843ec 100644
--- a/app/mailers/emails/remote_mirrors.rb
+++ b/app/mailers/emails/remote_mirrors.rb
@@ -6,7 +6,7 @@ module Emails
       @remote_mirror = RemoteMirrorFinder.new(id: remote_mirror_id).execute
       @project = @remote_mirror.project
 
-      mail(to: recipient(recipient_id), subject: subject('Remote mirror update failed'))
+      mail(to: recipient(recipient_id, @project.group), subject: subject('Remote mirror update failed'))
     end
   end
 end
diff --git a/app/mailers/notify.rb b/app/mailers/notify.rb
index 0b740809f30..4854ae5f0a7 100644
--- a/app/mailers/notify.rb
+++ b/app/mailers/notify.rb
@@ -73,12 +73,31 @@ class Notify < BaseMailer
 
   # Look up a User by their ID and return their email address
   #
-  # recipient_id - User ID
+  # recipient_id       - User ID
+  # notification_group - The parent group of the notification
   #
   # Returns a String containing the User's email address.
-  def recipient(recipient_id)
+  def recipient(recipient_id, notification_group = nil)
     @current_user = User.find(recipient_id)
-    @current_user.notification_email
+
+    if notification_group
+      group_notification_email = nil
+
+      # Get notification group's and ancestors' notification settings
+      group_ids = notification_group.self_and_ancestors_ids
+      notification_settings = notification_group.notification_settings.where(user: @current_user) # rubocop: disable CodeReuse/ActiveRecord
+
+      # Exploit notification_group.self_and_ancestors_ids being ordered from
+      # most nested to least nested to iterate through group ancestors
+      group_ids.each do |group_id|
+        group_notification_email = notification_settings.find { |ns| ns.source_id == group_id }&.notification_email
+        break if group_notification_email.present?
+      end
+    end
+
+    # Return group-specific email address if present, otherwise return global
+    # email address
+    group_notification_email.presence || @current_user.notification_email
   end
 
   # Formats arguments into a String suitable for use as an email subject