fix(dashboard): fix dynamic dashboard range (#436)

Fixes #430

---

_By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license_

Author: Eugene Cheung

lib/dashboard/DynamicDashboardFactory.ts

@@ -88,7 +88,9 @@ export class DynamicDashboardFactory
         dashboardConfig.renderingPreference ??
         DashboardRenderingPreference.INTERACTIVE_ONLY;
       const start: string =
-        "-" + (dashboardConfig.range ?? Duration.hours(8).toIsoString());
+        "-" +
+        (dashboardConfig.range?.toIsoString() ??
+          Duration.hours(8).toIsoString());
 
       const dashboard = this.createDashboard(
         renderingPreference,

test/dashboard/DynamicDashboardFactory.test.ts

@@ -1,4 +1,4 @@
-import { Stack } from "aws-cdk-lib";
+import { Duration, Stack } from "aws-cdk-lib";
 import { Template } from "aws-cdk-lib/assertions";
 import { IWidget, TextWidget } from "aws-cdk-lib/aws-cloudwatch";
 import { DynamicDashboardFactory, IDynamicDashboardSegment } from "../../lib";
@@ -28,7 +28,7 @@ test("dynamic dashboards created", () => {
     dashboardNamePrefix: "testPrefix",
     dashboardConfigs: [
       { name: TestDashboards.Dynamic1 },
-      { name: TestDashboards.Dynamic2 },
+      { name: TestDashboards.Dynamic2, range: Duration.days(7) },
     ],
   });
 
@@ -45,7 +45,7 @@ test("dynamic dashboards created", () => {
     DashboardName: "testPrefix-Dynamic1",
   });
   result.hasResourceProperties("AWS::CloudWatch::Dashboard", {
-    DashboardBody: `{"start":"-PT8H","periodOverride":"inherit","widgets":[{"type":"text","width":6,"height":2,"x":0,"y":0,"properties":{"markdown":"Dynamic2"}}]}`,
+    DashboardBody: `{"start":"-P7D","periodOverride":"inherit","widgets":[{"type":"text","width":6,"height":2,"x":0,"y":0,"properties":{"markdown":"Dynamic2"}}]}`,
     DashboardName: "testPrefix-Dynamic2",
   });
 });