Refactoring: Extract ActiveJob logic into concern to prevent/avoid fat class.

app/jobs/application_job.rb

@@ -1,21 +1,9 @@
 class ApplicationJob < ActiveJob::Base
+  include ApplicationJob::HasDelayedJobMonitoringCompatibilty
+
   # Automatically retry jobs that encountered a deadlock
   # retry_on ActiveRecord::Deadlocked
 
   # Most jobs are safe to ignore if the underlying records are no longer available
   # discard_on ActiveJob::DeserializationError
-
-  # We (currently) rely on Delayed::Job#attempts to check for stuck backends
-  # e.g. in the MonitoringController.
-  # This is a workaround to sync ActiveJob#executions to Delayed::Job#attempts
-  # until we resolve this dependency.
-  after_enqueue do |job|
-    # skip update of `attempts` attribute if job wasn't queued because of ActiveJobLock
-    #(another job with same lock key got queued before this job could be retried)
-    next if job.provider_job_id.blank?
-
-    # update the column right away without loading Delayed::Job record
-    # see: https://stackoverflow.com/a/34264580
-    Delayed::Job.where(id: job.provider_job_id).update_all(attempts: job.executions) # rubocop:disable Rails/SkipsModelValidations
-  end
 end

app/jobs/application_job/has_delayed_job_monitoring_compatibilty.rb

@@ -0,0 +1,21 @@
+class ApplicationJob
+  module HasDelayedJobMonitoringCompatibilty
+    extend ActiveSupport::Concern
+
+    included do
+      # We (currently) rely on Delayed::Job#attempts to check for stuck backends
+      # e.g. in the MonitoringController.
+      # This is a workaround to sync ActiveJob#executions to Delayed::Job#attempts
+      # until we resolve this dependency.
+      after_enqueue do |job|
+        # skip update of `attempts` attribute if job wasn't queued because of ActiveJobLock
+        #(another job with same lock key got queued before this job could be retried)
+        next if job.provider_job_id.blank?
+
+        # update the column right away without loading Delayed::Job record
+        # see: https://stackoverflow.com/a/34264580
+        Delayed::Job.where(id: job.provider_job_id).update_all(attempts: job.executions) # rubocop:disable Rails/SkipsModelValidations
+      end
+    end
+  end
+end