feat(aws-ecs): Add desired count to LoadBalanced[Fargate|EC2]Service (#1111)

Author: clareliguori

packages/@aws-cdk/aws-ecs/README.md

@@ -172,7 +172,7 @@ obtained from either DockerHub or from ECR repositories:
   DockerHub.
 * `ecs.ContaienrImage.fromEcrRepository(repo, tag)`: use the given ECR repository as the image
   to start.
-* `ecs.ContainerImage.fromAsset({ directory: './image' })`: build and upload an
+* `ecs.ContainerImage.fromAsset(this, 'Image', { directory: './image' })`: build and upload an
   image directly from a `Dockerfile` in your source directory.
 
 ### Service

packages/@aws-cdk/aws-ecs/lib/load-balanced-ecs-service.ts

@@ -54,6 +54,13 @@ export interface LoadBalancedEc2ServiceProps {
    * @default true
    */
   publicLoadBalancer?: boolean;
+
+  /**
+   * Number of desired copies of running tasks
+   *
+   * @default 1
+   */
+  desiredCount?: number;
 }
 
 /**
@@ -81,6 +88,7 @@ export class LoadBalancedEc2Service extends cdk.Construct {
 
     const service = new Ec2Service(this, "Service", {
       cluster: props.cluster,
+      desiredCount: props.desiredCount || 1,
       taskDefinition,
     });
 

packages/@aws-cdk/aws-ecs/lib/load-balanced-fargate-service-applet.ts

@@ -70,6 +70,13 @@ export interface LoadBalancedFargateServiceAppletProps extends cdk.StackProps {
    * @default false
    */
   publicTasks?: boolean;
+
+  /**
+   * Number of desired copies of running tasks
+   *
+   * @default 1
+   */
+  desiredCount?: number;
 }
 
 /**
@@ -91,6 +98,7 @@ export class LoadBalancedFargateServiceApplet extends cdk.Stack {
       publicLoadBalancer: props.publicLoadBalancer,
       publicTasks: props.publicTasks,
       image: DockerHub.image(props.image),
+      desiredCount: props.desiredCount,
     });
   }
 }

packages/@aws-cdk/aws-ecs/lib/load-balanced-fargate-service.ts

@@ -76,6 +76,13 @@ export interface LoadBalancedFargateServiceProps {
    * @default false
    */
   publicTasks?: boolean;
+
+  /**
+   * Number of desired copies of running tasks
+   *
+   * @default 1
+   */
+  desiredCount?: number;
 }
 
 /**
@@ -103,6 +110,7 @@ export class LoadBalancedFargateService extends cdk.Construct {
     const assignPublicIp = props.publicTasks !== undefined ? props.publicTasks : false;
     const service = new FargateService(this, "Service", {
       cluster: props.cluster,
+      desiredCount: props.desiredCount || 1,
       taskDefinition,
       assignPublicIp
     });

packages/@aws-cdk/aws-ecs/test/test.l3s.ts

@@ -16,12 +16,18 @@ export = {
     new ecs.LoadBalancedEc2Service(stack, 'Service', {
       cluster,
       memoryLimitMiB: 1024,
-      image: ecs.DockerHub.image('test')
+      image: ecs.DockerHub.image('test'),
+      desiredCount: 2
     });
 
-    // THEN - stack containers a load balancer
+    // THEN - stack containers a load balancer and a service
     expect(stack).to(haveResource('AWS::ElasticLoadBalancingV2::LoadBalancer'));
 
+    expect(stack).to(haveResource("AWS::ECS::Service", {
+      DesiredCount: 2,
+      LaunchType: "EC2",
+    }));
+
     test.done();
   },
 
@@ -34,12 +40,37 @@ export = {
     // WHEN
     new ecs.LoadBalancedFargateService(stack, 'Service', {
       cluster,
-      image: ecs.DockerHub.image('test')
+      image: ecs.DockerHub.image('test'),
+      desiredCount: 2
     });
 
-    // THEN - stack containers a load balancer
+    // THEN - stack contains a load balancer and a service
     expect(stack).to(haveResource('AWS::ElasticLoadBalancingV2::LoadBalancer'));
 
+    expect(stack).to(haveResource("AWS::ECS::Service", {
+      DesiredCount: 2,
+      LaunchType: "FARGATE",
+    }));
+
+    test.done();
+  },
+
+  'test Fargateloadbalanced applet'(test: Test) {
+    // WHEN
+    const app = new cdk.App();
+    const stack = new ecs.LoadBalancedFargateServiceApplet(app, 'Service', {
+      image: 'test',
+      desiredCount: 2
+    });
+
+    // THEN - stack contains a load balancer and a service
+    expect(stack).to(haveResource('AWS::ElasticLoadBalancingV2::LoadBalancer'));
+
+    expect(stack).to(haveResource("AWS::ECS::Service", {
+      DesiredCount: 2,
+      LaunchType: "FARGATE",
+    }));
+
     test.done();
   }
 };