creating background job

app/services/issues/base_service.rb

@@ -7,6 +7,12 @@ module Issues
       hook_data
     end
 
+    def schedule_due_date_email(issuable)
+      return if issuable.due_date.nil?
+
+      IssueDueWorker.perform_at(issuable.due_date.to_time, issuable.id)
+    end
+
     def reopen_service
       Issues::ReopenService
     end

app/services/issues/create_service.rb

@@ -27,6 +27,8 @@ module Issues
       todo_service.new_issue(issuable, current_user)
       user_agent_detail_service.create
       resolve_discussions_with_issue(issuable)
+      # TODO: Create the scheduled due date email
+      schedule_due_date_email(issuable)
 
       super
     end

app/services/issues/update_service.rb

@@ -13,6 +13,10 @@ module Issues
       spam_check(issue, current_user)
     end
 
+    def after_update(issue)
+      schedule_due_date_email(issue)
+    end
+
     def handle_changes(issue, options)
       old_associations = options.fetch(:old_associations, {})
       old_labels = old_associations.fetch(:labels, [])
@@ -23,6 +27,9 @@ module Issues
         todo_service.mark_pending_todos_as_done(issue, current_user)
       end
 
+      # TODO: If due date doesn't change, don't bother updating the due date
+      # email worker
+
       if issue.previous_changes.include?('title') ||
           issue.previous_changes.include?('description')
         todo_service.update_issue(issue, current_user, old_mentioned_users)

app/workers/all_queues.yml

@@ -78,6 +78,7 @@
 - group_destroy
 - invalid_gpg_signature_update
 - irker
+- issue_due
 - merge
 - namespaceless_project_destroy
 - new_issue

app/workers/issue_due_worker.rb

+class IssueDueWorker
+  include ApplicationWorker
+
+  def perform(issue_id)
+    issue = Issue.find_by_id(issue_id)
+    # How do we want to deal with noops?
+    if issue.due_date == Date.today
+      # execute
+    end
+  end
+end