Add a system note on Alert creation

We add a base set of creating system
notes when creating generic and
prometheus alerts.

app/helpers/system_note_helper.rb

@@ -33,7 +33,8 @@ module SystemNoteHelper
     'designs_removed' => 'doc-image',
     'designs_discussion_added' => 'doc-image',
     'status' => 'status',
-    'alert_issue_added' => 'issues'
+    'alert_issue_added' => 'issues',
+    'new_alert_added' => 'warning'
   }.freeze
 
   def system_note_icon_name(note)

app/models/system_note_metadata.rb

@@ -20,7 +20,7 @@ class SystemNoteMetadata < ApplicationRecord
     title time_tracking branch milestone discussion task moved
     opened closed merged duplicate locked unlocked outdated
     tag due_date pinned_embed cherry_pick health_status approved unapproved
-    status alert_issue_added relate unrelate
+    status alert_issue_added relate unrelate new_alert_added
   ].freeze
 
   validates :note, presence: true

app/services/alert_management/process_prometheus_alert_service.rb

@@ -54,6 +54,7 @@ module AlertManagement
       if new_alert.save
         new_alert.execute_services
         @am_alert = new_alert
+        SystemNoteService.create_new_alert(new_alert, Gitlab::AlertManagement::AlertParams::MONITORING_TOOLS[:prometheus])
         return
       end
 

app/services/projects/alerting/notify_service.rb

@@ -48,6 +48,7 @@ module Projects
       def create_alert
         alert = AlertManagement::Alert.create(am_alert_params)
         alert.execute_services if alert.persisted?
+        SystemNoteService.create_new_alert(alert, 'Generic Alert Endpoint')
 
         alert
       end

app/services/system_note_service.rb

@@ -308,6 +308,10 @@ module SystemNoteService
     ::SystemNotes::AlertManagementService.new(noteable: alert, project: alert.project, author: author).new_alert_issue(issue)
   end
 
+  def create_new_alert(alert, monitoring_tool)
+    ::SystemNotes::AlertManagementService.new(noteable: alert, project: alert.project).create_new_alert(monitoring_tool)
+  end
+
   private
 
   def merge_requests_service(noteable, project, author)

app/services/system_notes/alert_management_service.rb

@@ -2,6 +2,21 @@
 
 module SystemNotes
   class AlertManagementService < ::SystemNotes::BaseService
+    # Called when the a new AlertManagement::Alert has been created
+    #
+    # alert - AlertManagement::Alert object.
+    #
+    # Example Note text:
+    #
+    #   "GitLab Alert Bot logged an alert from Prometheus"
+    #
+    # Returns the created Note object
+    def create_new_alert(monitoring_tool)
+      body = "logged an alert from **#{monitoring_tool}**"
+
+      create_note(NoteSummary.new(noteable, project, User.alert_bot, body, action: 'new_alert_added'))
+    end
+
     # Called when the status of an AlertManagement::Alert has changed
     #
     # alert - AlertManagement::Alert object.

changelogs/unreleased/225820-create-system-note-alert.yml

+---
+title: Add a system note on Alert creation
+merge_request: 40128
+author:
+type: added

spec/services/alert_management/process_prometheus_alert_service_spec.rb

@@ -84,6 +84,10 @@ RSpec.describe AlertManagement::ProcessPrometheusAlertService do
           context 'when alert can be created' do
             it_behaves_like 'creates an alert management alert'
 
+            it 'creates a system note corresponding to alert creation' do
+              expect { subject }.to change(Note, :count).by(1)
+            end
+
             it 'processes the incident alert' do
               expect(IncidentManagement::ProcessAlertWorker)
                 .to receive(:perform_async)

spec/services/projects/alerting/notify_service_spec.rb

@@ -123,6 +123,10 @@ RSpec.describe Projects::Alerting::NotifyService do
           it_behaves_like 'creates an alert management alert'
           it_behaves_like 'assigns the alert properties'
 
+          it 'creates a system note corresponding to alert creation' do
+            expect { subject }.to change(Note, :count).by(1)
+          end
+
           context 'existing alert with same fingerprint' do
             let(:fingerprint_sha) { Digest::SHA1.hexdigest(fingerprint) }
             let!(:alert) { create(:alert_management_alert, project: project, fingerprint: fingerprint_sha) }

spec/services/system_note_service_spec.rb

@@ -739,4 +739,17 @@ RSpec.describe SystemNoteService do
       described_class.new_alert_issue(alert, alert.issue, author)
     end
   end
+
+  describe '.create_new_alert' do
+    let(:alert) { build(:alert_management_alert) }
+    let(:monitoring_tool) { 'Prometheus' }
+
+    it 'calls AlertManagementService' do
+      expect_next_instance_of(SystemNotes::AlertManagementService) do |service|
+        expect(service).to receive(:create_new_alert).with(monitoring_tool)
+      end
+
+      described_class.create_new_alert(alert, monitoring_tool)
+    end
+  end
 end

spec/services/system_notes/alert_management_service_spec.rb

@@ -7,6 +7,19 @@ RSpec.describe ::SystemNotes::AlertManagementService do
   let_it_be(:project)  { create(:project, :repository) }
   let_it_be(:noteable) { create(:alert_management_alert, :with_issue, :acknowledged, project: project) }
 
+  describe '#create_new_alert' do
+    subject { described_class.new(noteable: noteable, project: project).create_new_alert('Some Service') }
+
+    it_behaves_like 'a system note' do
+      let(:author) { User.alert_bot }
+      let(:action) { 'new_alert_added' }
+    end
+
+    it 'has the appropriate message' do
+      expect(subject.note).to eq('logged an alert from **Some Service**')
+    end
+  end
+
   describe '#change_alert_status' do
     subject { described_class.new(noteable: noteable, project: project, author: author).change_alert_status(noteable) }