feat(ecs): add metrics for Fargate services (#2798)

The `BaseService` class had a `metric()` implementation missing the `clusterName` dimension (it was
overriden in `Ec2Service` with a correct implementation).

Moved correct `metric()`, `metricCpuUtilization()` and `metricMemoryUtilization()` methods to
`BaseService`. Both `Ec2Service` and `FargateService` now have correct `metricXxx()` methods.

Added tests for `metricXxx()` methods.

Author: jogold

packages/@aws-cdk/aws-ecs/lib/base/base-service.ts

@@ -227,11 +227,29 @@ export abstract class BaseService extends Resource
     return new cloudwatch.Metric({
       namespace: 'AWS/ECS',
       metricName,
-      dimensions: { ServiceName: this.serviceName },
+      dimensions: { ClusterName: this.clusterName, ServiceName: this.serviceName },
       ...props
     });
   }
 
+  /**
+   * Metric for cluster Memory utilization
+   *
+   * @default average over 5 minutes
+   */
+  public metricMemoryUtilization(props?: cloudwatch.MetricOptions): cloudwatch.Metric {
+    return this.metric('MemoryUtilization', props);
+  }
+
+  /**
+   * Metric for cluster CPU utilization
+   *
+   * @default average over 5 minutes
+   */
+  public metricCpuUtilization(props?: cloudwatch.MetricOptions): cloudwatch.Metric {
+    return this.metric('CPUUtilization', props);
+  }
+
   /**
    * Set up AWSVPC networking for this construct
    */

packages/@aws-cdk/aws-ecs/lib/ec2/ec2-service.ts

@@ -1,4 +1,3 @@
-import cloudwatch = require ('@aws-cdk/aws-cloudwatch');
 import ec2 = require('@aws-cdk/aws-ec2');
 import elb = require('@aws-cdk/aws-elasticloadbalancing');
 import { Construct, Lazy, Resource } from '@aws-cdk/cdk';
@@ -242,36 +241,6 @@ export class Ec2Service extends BaseService implements IEc2Service, elb.ILoadBal
     });
   }
 
-  /**
-   * Return the given named metric for this Service
-   */
-  public metric(metricName: string, props?: cloudwatch.MetricOptions): cloudwatch.Metric {
-    return new cloudwatch.Metric({
-      namespace: 'AWS/ECS',
-      metricName,
-      dimensions: { ClusterName: this.clusterName, ServiceName: this.serviceName },
-      ...props
-    });
-  }
-
-  /**
-   * Metric for cluster Memory utilization
-   *
-   * @default average over 5 minutes
-   */
-  public metricMemoryUtilization(props?: cloudwatch.MetricOptions): cloudwatch.Metric {
-    return this.metric('MemoryUtilization', props );
-  }
-
-  /**
-   * Metric for cluster CPU utilization
-   *
-   * @default average over 5 minutes
-   */
-  public metricCpuUtilization(props?: cloudwatch.MetricOptions): cloudwatch.Metric {
-    return this.metric('CPUUtilization', props);
-  }
-
   /**
    * Validate this Ec2Service
    */

packages/@aws-cdk/aws-ecs/test/ec2/test.ec2-service.ts

@@ -1007,5 +1007,37 @@ export = {
 
       test.done();
     },
+  },
+
+  'Metric'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'MyVpc', {});
+    const cluster = new ecs.Cluster(stack, 'EcsCluster', { vpc });
+    cluster.addCapacity('DefaultAutoScalingGroup', { instanceType: new ec2.InstanceType('t2.micro') });
+    const taskDefinition = new ecs.Ec2TaskDefinition(stack, 'FargateTaskDef');
+    taskDefinition.addContainer('Container', {
+      image: ecs.ContainerImage.fromRegistry('hello')
+    });
+
+    // WHEN
+    const service = new ecs.Ec2Service(stack, 'Service', {
+      cluster,
+      taskDefinition,
+    });
+
+    // THEN
+    test.deepEqual(stack.resolve(service.metricMemoryUtilization()), {
+      dimensions: {
+        ClusterName: { Ref: 'EcsCluster97242B84' },
+        ServiceName: { 'Fn::GetAtt': ['ServiceD69D759B', 'Name'] }
+      },
+      namespace: 'AWS/ECS',
+      metricName: 'MemoryUtilization',
+      periodSec: 300,
+      statistic: 'Average'
+    });
+
+    test.done();
   }
 };

packages/@aws-cdk/aws-ecs/test/fargate/test.fargate-service.ts

@@ -467,5 +467,36 @@ export = {
 
       test.done();
     },
+  },
+
+  'Metric'(test: Test) {
+    // GIVEN
+    const stack = new cdk.Stack();
+    const vpc = new ec2.Vpc(stack, 'MyVpc', {});
+    const cluster = new ecs.Cluster(stack, 'EcsCluster', { vpc });
+    const taskDefinition = new ecs.FargateTaskDefinition(stack, 'FargateTaskDef');
+    taskDefinition.addContainer('Container', {
+      image: ecs.ContainerImage.fromRegistry('hello')
+    });
+
+    // WHEN
+    const service = new ecs.FargateService(stack, 'Service', {
+      cluster,
+      taskDefinition,
+    });
+
+    // THEN
+    test.deepEqual(stack.resolve(service.metricCpuUtilization()), {
+      dimensions: {
+        ClusterName: { Ref: 'EcsCluster97242B84' },
+        ServiceName: { 'Fn::GetAtt': ['ServiceD69D759B', 'Name'] }
+      },
+      namespace: 'AWS/ECS',
+      metricName: 'CPUUtilization',
+      periodSec: 300,
+      statistic: 'Average'
+    });
+
+    test.done();
   }
 };