Create concern for self-monitoring workers

* Move common code from the creation and deletion workers into the
concern.

* Remove the lib/gitlab/self_monitoring.rb file since the constant it
contained is now in the concern.

app/workers/concerns/self_monitoring_project_worker.rb

+# frozen_string_literal: true
+
+module SelfMonitoringProjectWorker
+  extend ActiveSupport::Concern
+
+  included do
+    # This worker falls under Self-monitoring with Monitor::APM group. However,
+    # self-monitoring is not classified as a feature category but rather as
+    # Other Functionality. Metrics seems to be the closest feature_category for
+    # this worker.
+    feature_category :metrics
+  end
+
+  LEASE_TIMEOUT = 15.minutes.to_i
+  EXCLUSIVE_LEASE_KEY = 'self_monitoring_service_creation_deletion'
+
+  class_methods do
+    # @param job_id [String]
+    #   Job ID that is used to construct the cache keys.
+    # @return [Hash]
+    #   Returns true if the job is enqueued or in progress and false otherwise.
+    def in_progress?(job_id)
+      Gitlab::SidekiqStatus.job_status(Array.wrap(job_id)).first
+    end
+  end
+
+  private
+
+  def lease_key
+    EXCLUSIVE_LEASE_KEY
+  end
+
+  def lease_timeout
+    self.class::LEASE_TIMEOUT
+  end
+end

app/workers/self_monitoring_project_create_worker.rb

@@ -3,36 +3,11 @@
 class SelfMonitoringProjectCreateWorker
   include ApplicationWorker
   include ExclusiveLeaseGuard
-
-  # This worker falls under Self-monitoring with Monitor::APM group. However,
-  # self-monitoring is not classified as a feature category but rather as
-  # Other Functionality. Metrics seems to be the closest feature_category for
-  # this worker.
-  feature_category :metrics
-
-  LEASE_TIMEOUT = 15.minutes.to_i
+  include SelfMonitoringProjectWorker
 
   def perform
     try_obtain_lease do
       Gitlab::DatabaseImporters::SelfMonitoring::Project::CreateService.new.execute
     end
   end
-
-  # @param job_id [String]
-  #   Job ID that is used to construct the cache keys.
-  # @return [Hash]
-  #   Returns true if the job is enqueued or in progress and false otherwise.
-  def self.in_progress?(job_id)
-    Gitlab::SidekiqStatus.job_status(Array.wrap(job_id)).first
-  end
-
-  private
-
-  def lease_key
-    Gitlab::SelfMonitoring::PROJECT_CREATION_DELETION_WORKER_EXCLUSIVE_LEASE_KEY
-  end
-
-  def lease_timeout
-    LEASE_TIMEOUT
-  end
 end

app/workers/self_monitoring_project_delete_worker.rb

@@ -3,36 +3,11 @@
 class SelfMonitoringProjectDeleteWorker
   include ApplicationWorker
   include ExclusiveLeaseGuard
-
-  # This worker falls under Self-monitoring with Monitor::APM group. However,
-  # self-monitoring is not classified as a feature category but rather as
-  # Other Functionality. Metrics seems to be the closest feature_category for
-  # this worker.
-  feature_category :metrics
-
-  LEASE_TIMEOUT = 15.minutes.to_i
+  include SelfMonitoringProjectWorker
 
   def perform
     try_obtain_lease do
       Gitlab::DatabaseImporters::SelfMonitoring::Project::DeleteService.new.execute
     end
   end
-
-  # @param job_id [String]
-  #   Job ID that is used to construct the cache keys.
-  # @return [Hash]
-  #   Returns true if the job is enqueued or in progress and false otherwise.
-  def self.in_progress?(job_id)
-    Gitlab::SidekiqStatus.job_status(Array.wrap(job_id)).first
-  end
-
-  private
-
-  def lease_key
-    Gitlab::SelfMonitoring::PROJECT_CREATION_DELETION_WORKER_EXCLUSIVE_LEASE_KEY
-  end
-
-  def lease_timeout
-    LEASE_TIMEOUT
-  end
 end

lib/gitlab/self_monitoring.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module SelfMonitoring
-    PROJECT_CREATION_DELETION_WORKER_EXCLUSIVE_LEASE_KEY = 'self_monitoring_service_creation_deletion'
-  end
-end

spec/support/shared_examples/workers/self_monitoring_shared_examples.rb

@@ -8,7 +8,7 @@ RSpec.shared_examples 'executes service' do
     allow(service_class).to receive(:new) { service }
   end
 
-  it 'runs the SelfMonitoring::Project::CreateService' do
+  it 'runs the service' do
     expect(service).to receive(:execute)
 
     subject.perform