Alert Assignement Todo: auto add a todo assignment

Add an assignment todo automatically when an alert
is assigned via the sidebar.

app/services/alert_management/alerts/update_service.rb

@@ -3,6 +3,8 @@
 module AlertManagement
   module Alerts
     class UpdateService
+      include Gitlab::Utils::StrongMemoize
+
       # @param alert [AlertManagement::Alert]
       # @param current_user [User]
       # @param params [Hash] Attributes of the alert
@@ -19,6 +21,7 @@ module AlertManagement
         filter_assignees
 
         if alert.update(params)
+          assign_todo
           success
         else
           error(alert.errors.full_messages.to_sentence)
@@ -29,6 +32,12 @@ module AlertManagement
 
       attr_reader :alert, :current_user, :params
 
+      def assign_todo
+        return unless assignee
+
+        todo_service.assign_alert(alert, assignee)
+      end
+
       def allowed?
         current_user.can?(:update_alert_management_alert, alert)
       end
@@ -36,8 +45,20 @@ module AlertManagement
       def filter_assignees
         return if params[:assignees].nil?
 
+        params[:assignees] = Array(assignee)
+      end
+
+      def assignee
+        strong_memoize(:assignee) do
           # Take first assignee while multiple are not currently supported
-        params[:assignees] = Array(params[:assignees].first)
+          params[:assignees]&.first
+        end
+      end
+
+      def todo_service
+        strong_memoize(:todo_service) do
+          TodoService.new
+        end
       end
 
       def success

changelogs/unreleased/215946-add-gitlab-to-do-for-user-when-they-are-assigned-to-an-alert.yml

+---
+title: Add todo when alert is assigned to a user
+merge_request: 34104
+author:
+type: added

spec/services/alert_management/alerts/update_service_spec.rb

@@ -45,7 +45,7 @@ describe AlertManagement::Alerts::UpdateService do
       end
     end
 
-    context 'when a model attribute is included' do
+    context 'when a model attribute is included without assignees' do
       let(:params) { { title: 'This is an updated alert.' } }
 
       it 'updates the attribute' do
@@ -54,6 +54,10 @@ describe AlertManagement::Alerts::UpdateService do
         expect { response }.to change { alert.title }.from(original_title).to(params[:title])
         expect(response).to be_success
       end
+
+      it 'skips adding a todo' do
+        expect { response }.not_to change(Todo, :count)
+      end
     end
 
     context 'when assignees are included' do
@@ -76,6 +80,10 @@ describe AlertManagement::Alerts::UpdateService do
           expect(response).to be_success
         end
       end
+
+      it 'adds a todo' do
+        expect { response }.to change { Todo.where(user: user_with_permissions).count }.by(1)
+      end
     end
   end
 end