1 files changed, 98 insertions, 0 deletions
diff --git a/app/services/alert_management/alerts/update_service.rb b/app/services/alert_management/alerts/update_service.rb
new file mode 100644
index 00000000000..ffabbb37289
--- /dev/null
+++ b/app/services/alert_management/alerts/update_service.rb
@@ -0,0 +1,98 @@
+# frozen_string_literal: true
+
+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
+      def initialize(alert, current_user, params)
+        @alert = alert
+        @current_user = current_user
+        @params = params
+      end
+
+      def execute
+        return error_no_permissions unless allowed?
+        return error_no_updates if params.empty?
+
+        filter_assignees
+        old_assignees = alert.assignees.to_a
+
+        if alert.update(params)
+          process_assignement(old_assignees)
+
+          success
+        else
+          error(alert.errors.full_messages.to_sentence)
+        end
+      end
+
+      private
+
+      attr_reader :alert, :current_user, :params
+
+      def allowed?
+        current_user&.can?(:update_alert_management_alert, alert)
+      end
+
+      def assignee_todo_allowed?
+        assignee&.can?(:read_alert_management_alert, alert)
+      end
+
+      def todo_service
+        strong_memoize(:todo_service) do
+          TodoService.new
+        end
+      end
+
+      def success
+        ServiceResponse.success(payload: { alert: alert })
+      end
+
+      def error(message)
+        ServiceResponse.error(payload: { alert: alert }, message: message)
+      end
+
+      def error_no_permissions
+        error(_('You have no permissions'))
+      end
+
+      def error_no_updates
+        error(_('Please provide attributes to update'))
+      end
+
+      # ----- Assignee-related behavior ------
+      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]&.first
+        end
+      end
+
+      def process_assignement(old_assignees)
+        assign_todo
+        add_assignee_system_note(old_assignees)
+      end
+
+      def assign_todo
+        # Remove check in follow-up issue https://gitlab.com/gitlab-org/gitlab/-/issues/222672
+        return unless assignee_todo_allowed?
+
+        todo_service.assign_alert(alert, current_user)
+      end
+
+      def add_assignee_system_note(old_assignees)
+        SystemNoteService.change_issuable_assignees(alert, alert.project, current_user, old_assignees)
+      end
+    end
+  end
+end