Add tweaks to worker, service, specs

- Add docs page

doc/operations/incident_management/incidents.md

@@ -184,3 +184,9 @@ To quickly see the latest updates on an incident, click
 un-threaded and ordered chronologically, newest to oldest:
 
 ![Timeline view toggle](./img/timeline_view_toggle_v13_5.png)
+
+### Service Level Agreement Countdown Timer
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/241663) in GitLab 13.5.
+
+If you have enabled Incident SLA in the Incident Management Configuration then you will see an SLA timer for your newly created incidents. The timer will show the time left to close in incident within the configured SLA time period. If an incident is not closed before the SLA is exceeded, then a `missed::SLA` label is added to the incident.

ee/app/services/incident_management/apply_incident_sla_exceeded_label_service.rb

@@ -6,7 +6,7 @@ module IncidentManagement
       super(incident.project)
 
       @incident = incident
-      @label = incident_exceeded_label
+      @label = incident_exceeded_sla_label
     end
 
     def execute
@@ -28,7 +28,7 @@ module IncidentManagement
         .execute(added_labels: [label])
     end
 
-    def incident_exceeded_label
+    def incident_exceeded_sla_label
       ::IncidentManagement::CreateIncidentSlaExceededLabelService
         .new(project)
         .execute

ee/app/services/incident_management/create_incident_sla_exceeded_label_service.rb

@@ -6,7 +6,7 @@ module IncidentManagement
       title: 'missed::SLA',
       color: '#D9534F',
       description: <<~DESCRIPTION.chomp
-        Incidents that have missed the targeted SLA (Service Level Agreement).
+        Incidents that have missed the targeted SLA (Service Level Agreement). https://docs.gitlab.com/ee/operations/incident_management/incidents.html#service-level-agreement-countdown-timer
       DESCRIPTION
     }.freeze
 

ee/app/workers/all_queues.yml

@@ -201,7 +201,7 @@
   :urgency: :low
   :resource_boundary: :unknown
   :weight: 1
-  :idempotent:
+  :idempotent: true
   :tags: []
 - :name: cronjob:ingress_modsecurity_counter_metrics
   :feature_category: :web_firewall

ee/app/workers/incident_management/incident_sla_exceeded_check_worker.rb

@@ -5,12 +5,17 @@ module IncidentManagement
     include ApplicationWorker
     include CronjobQueue # rubocop:disable Scalability/CronWorkerContext
 
+
+    idempotent!
     feature_category :incident_management
 
     def perform
       IncidentSla.exceeded.find_in_batches do |incident_slas|
         incident_slas.each do |incident_sla|
           ApplyIncidentSlaExceededLabelService.new(incident_sla.issue).execute
+
+          rescue StandardError => e
+          Gitlab::AppLogger.error("Error encountered in #{self.class.name}: #{e}")
         end
       end
     end

ee/spec/factories/issuable_sla.rb

@@ -4,5 +4,9 @@ FactoryBot.define do
   factory :issuable_sla do
     issue
     due_at { 1.hour.from_now }
+
+    trait :exceeded do
+      due_at { 1.hour.ago }
+    end
   end
 end

ee/spec/workers/incident_management/incident_sla_exceeded_check_worker_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe IncidentManagement::IncidentSlaExceededCheckWorker do
+  let(:worker) { described_class.new }
+
+  describe '#perform' do
+    subject(:perform) { worker.perform }
+
+    let_it_be(:incident_1) { create(:incident_sla, :exceeded) }
+    let_it_be(:incident_2) { create(:incident_sla, :exceeded) }
+    let_it_be(:incident_3) { create(:incident_sla, :exceeded) }
+
+    let(:label_service_stub) { instance_double(IncidentManagement::ApplyIncidentSlaExceededLabelService, execute: true) }
+
+    it 'calls the apply incident sla label service' do
+      expect(IncidentManagement::ApplyIncidentSlaExceededLabelService)
+        .to receive(:new)
+        .exactly(3)
+        .and_return(label_service_stub)
+
+      expect(label_service_stub).to receive(:execute).exactly(3).times
+
+      perform
+    end
+
+    context 'when error occurs' do
+      before do
+        allow(IncidentManagement::ApplyIncidentSlaExceededLabelService)
+          .to receive(:new)
+          .and_return(label_service_stub)
+
+        allow(IncidentManagement::ApplyIncidentSlaExceededLabelService)
+          .to receive(:new)
+          .with(incident_1.issue)
+          .and_raise('test')
+      end
+
+      it 'logs the error and continues to run the others' do
+        expect(Gitlab::AppLogger).to receive(:error).once
+        expect(label_service_stub).to receive(:execute).exactly(2).times
+
+        perform
+      end
+    end
+  end
+end