feat(ecs-patterns): allow imported IBaseService (#471)

The existing logic to get metrics on `BaseService` [is pretty simple](https://github.com/aws/aws-cdk/blob/v2.115.0/packages/aws-cdk-lib/aws-ecs/lib/base/base-service.ts#L1195-L1220) and can probably be lifted up to `IBaseService` upstream (similar [to the change for load balancers](aws/aws-cdk@cb889bc)), but I don't have bandwidth to tackle that right now.

---

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

Author: Eugene Cheung

API.md

@@ -1,44 +1,60 @@
-import { BaseService } from "aws-cdk-lib/aws-ecs";
+import { DimensionsMap } from "aws-cdk-lib/aws-cloudwatch";
+import { IBaseService } from "aws-cdk-lib/aws-ecs";
 
 import { MetricFactory, MetricStatistic } from "../../common";
 
+const EcsNamespace = "AWS/ECS";
 const EcsContainerInsightsNamespace = "ECS/ContainerInsights";
 
 /**
  * Props to create BaseServiceMetricFactory.
  */
 export interface BaseServiceMetricFactoryProps {
-  readonly service: BaseService;
+  readonly service: IBaseService;
 }
 
 /**
  * Metric factory for a base service (parent class for e.g. Fargate and EC2 services).
  */
 export class BaseServiceMetricFactory {
   protected readonly metricFactory: MetricFactory;
-  protected readonly service: BaseService;
+  protected readonly dimensionsMap: DimensionsMap;
+  /**
+   * @deprecated This isn't required by cdk-monitoring-constructs anymore; use your own reference.
+   */
+  protected readonly service: IBaseService;
 
   constructor(
     metricFactory: MetricFactory,
     props: BaseServiceMetricFactoryProps
   ) {
     this.metricFactory = metricFactory;
+    this.dimensionsMap = {
+      ClusterName: props.service.cluster.clusterName,
+      ServiceName: props.service.serviceName,
+    };
     this.service = props.service;
   }
 
   metricClusterCpuUtilisationInPercent() {
-    return this.metricFactory.adaptMetric(
-      this.service.metricCpuUtilization({
-        label: "Cluster CPU Utilization",
-      })
+    return this.metricFactory.createMetric(
+      "CPUUtilization",
+      MetricStatistic.AVERAGE,
+      "Cluster CPU Utilization",
+      this.dimensionsMap,
+      undefined,
+      EcsNamespace
     );
   }
 
   metricClusterMemoryUtilisationInPercent() {
-    return this.metricFactory.adaptMetric(
-      this.service.metricMemoryUtilization({
-        label: "Cluster Memory Utilization",
-      })
+    return this.metricFactory.createMetric(
+      "MemoryUtilization",
+      MetricStatistic.AVERAGE,
+      "Cluster Memory Utilization",
+      this.dimensionsMap,
+      undefined,
+      EcsNamespace
     );
   }
 
@@ -47,10 +63,7 @@ export class BaseServiceMetricFactory {
       "RunningTaskCount",
       MetricStatistic.AVERAGE,
       "Running Tasks",
-      {
-        ServiceName: this.service.serviceName,
-        ClusterName: this.service.cluster.clusterName,
-      },
+      this.dimensionsMap,
       undefined,
       EcsContainerInsightsNamespace
     );

lib/monitoring/aws-ecs-patterns/BaseServiceMetricFactory.ts

@@ -4,7 +4,7 @@ import {
   IMetric,
   IWidget,
 } from "aws-cdk-lib/aws-cloudwatch";
-import { Ec2Service } from "aws-cdk-lib/aws-ecs";
+import { Ec2Service, IBaseService } from "aws-cdk-lib/aws-ecs";
 import {
   ApplicationLoadBalancedEc2Service,
   NetworkLoadBalancedEc2Service,
@@ -147,7 +147,7 @@ export interface Ec2ApplicationLoadBalancerMonitoringProps
 
 export interface CustomEc2ServiceMonitoringProps
   extends BaseLoadBalancedEc2ServiceMonitoringProps {
-  readonly ec2Service: Ec2Service;
+  readonly ec2Service: IBaseService;
   readonly loadBalancer?: IApplicationLoadBalancer | INetworkLoadBalancer;
   readonly targetGroup?: IApplicationTargetGroup | INetworkTargetGroup;
 }

lib/monitoring/aws-ecs-patterns/Ec2ServiceMonitoring.ts

@@ -4,7 +4,7 @@ import {
   IMetric,
   IWidget,
 } from "aws-cdk-lib/aws-cloudwatch";
-import { FargateService } from "aws-cdk-lib/aws-ecs";
+import { FargateService, IBaseService } from "aws-cdk-lib/aws-ecs";
 import {
   ApplicationLoadBalancedFargateService,
   NetworkLoadBalancedFargateService,
@@ -147,7 +147,7 @@ export interface FargateApplicationLoadBalancerMonitoringProps
 
 export interface CustomFargateServiceMonitoringProps
   extends BaseLoadBalancedFargateServiceMonitoringProps {
-  readonly fargateService: FargateService;
+  readonly fargateService: IBaseService;
   readonly loadBalancer?: IApplicationLoadBalancer | INetworkLoadBalancer;
   readonly targetGroup?: IApplicationTargetGroup | INetworkTargetGroup;
 }

lib/monitoring/aws-ecs-patterns/FargateServiceMonitoring.ts

@@ -2,7 +2,7 @@ import { Stack } from "aws-cdk-lib";
 import { Template } from "aws-cdk-lib/assertions";
 import { InstanceType } from "aws-cdk-lib/aws-ec2";
 import { Repository } from "aws-cdk-lib/aws-ecr";
-import { Cluster, EcrImage } from "aws-cdk-lib/aws-ecs";
+import { Cluster, Ec2Service, EcrImage } from "aws-cdk-lib/aws-ecs";
 import {
   ApplicationLoadBalancedEc2Service,
   NetworkLoadBalancedEc2Service,
@@ -261,3 +261,29 @@ import { TestMonitoringScope } from "../TestMonitoringScope";
     });
   }
 );
+
+test("snapshot test: with imported service", () => {
+  const stack = new Stack();
+
+  const importedService = Ec2Service.fromEc2ServiceAttributes(
+    stack,
+    "ImportedEc2Service",
+    {
+      cluster: Cluster.fromClusterArn(
+        stack,
+        "ImportedCluster",
+        "arn:aws:ecs:us-west-2:123456789012:cluster/DummyCluster"
+      ),
+      serviceName: "DummyService",
+    }
+  );
+
+  const scope = new TestMonitoringScope(stack, "Scope");
+  const monitoring = new Ec2ServiceMonitoring(scope, {
+    ec2Service: importedService,
+    alarmFriendlyName: "DummyEc2Service",
+  });
+
+  addMonitoringDashboardsToStack(stack, monitoring);
+  expect(Template.fromStack(stack)).toMatchSnapshot();
+});

test/monitoring/aws-ecs-patterns/Ec2ServiceMonitoring.test.ts

@@ -457,3 +457,29 @@ import { TestMonitoringScope } from "../TestMonitoringScope";
     });
   }
 );
+
+test("snapshot test: with imported service", () => {
+  const stack = new Stack();
+
+  const importedService = FargateService.fromFargateServiceAttributes(
+    stack,
+    "ImportedEc2Service",
+    {
+      cluster: Cluster.fromClusterArn(
+        stack,
+        "ImportedCluster",
+        "arn:aws:ecs:us-west-2:123456789012:cluster/DummyCluster"
+      ),
+      serviceName: "DummyService",
+    }
+  );
+
+  const scope = new TestMonitoringScope(stack, "Scope");
+  const monitoring = new FargateServiceMonitoring(scope, {
+    fargateService: importedService,
+    alarmFriendlyName: "DummyFargateService",
+  });
+
+  addMonitoringDashboardsToStack(stack, monitoring);
+  expect(Template.fromStack(stack)).toMatchSnapshot();
+});