feat(batch): fargate support for jobs

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

@@ -37,7 +37,7 @@ For more information on **AWS Batch** visit the [AWS Docs for Batch](https://doc
 
 ## Compute Environment
 
-At the core of AWS Batch is the compute environment. All batch jobs are processed within a compute environment, which uses resource like OnDemand or Spot EC2 instances.
+At the core of AWS Batch is the compute environment. All batch jobs are processed within a compute environment, which uses resource like OnDemand/Spot EC2 instances or Fargate.
 
 In **MANAGED** mode, AWS will handle the provisioning of compute resources to accommodate the demand. Otherwise, in **UNMANAGED** mode, you will need to manage the provisioning of those resources.
 
@@ -74,6 +74,21 @@ const spotEnvironment = new batch.ComputeEnvironment(stack, 'MySpotEnvironment',
 });
 ```
 
+### Fargate Compute Environment
+
+It is possible to have AWS Batch submit jobs to be run on Fargate compute resources. Below is an example of how this can be done:
+
+```ts
+const vpc = new ec2.Vpc(this, 'VPC');
+
+const fargateSpotEnvironment = new batch.ComputeEnvironment(stack, 'MyFargateEnvironment', {
+  computeResources: {
+    type: batch.ComputeResourceType.FARGATE_SPOT,
+    vpc,
+  },
+});
+```
+
 ### Understanding Progressive Allocation Strategies
 
 AWS Batch uses an [allocation strategy](https://docs.aws.amazon.com/batch/latest/userguide/allocation-strategies.html) to determine what compute resource will efficiently handle incoming job requests. By default, **BEST_FIT** will pick an available compute instance based on vCPU requirements. If none exist, the job will wait until resources become available. However, with this strategy, you may have jobs waiting in the queue unnecessarily despite having more powerful instances available. Below is an example of how that situation might look like:

packages/@aws-cdk/aws-batch/lib/compute-environment.ts

@@ -6,7 +6,7 @@ import { CfnComputeEnvironment } from './batch.generated';
 
 /**
  * Property to specify if the compute environment
- * uses On-Demand or SpotFleet compute resources.
+ * uses On-Demand, SpotFleet, Fargate, or Fargate Spot compute resources.
  */
 export enum ComputeResourceType {
   /**
@@ -18,6 +18,20 @@ export enum ComputeResourceType {
    * Resources will be EC2 SpotFleet resources.
    */
   SPOT = 'SPOT',
+
+  /**
+   * Resources will be Fargate resources.
+   */
+  FARGATE = 'FARGATE',
+
+  /**
+   * Resources will be Fargate Spot resources.
+   *
+   * Fargate Spot uses spare capacity in the AWS cloud to run your fault-tolerant,
+   * time-flexible jobs at up to a 70% discount. If AWS needs the resources back,
+   * jobs running on Fargate Spot will be interrupted with two minutes of notification.
+   */
+  FARGATE_SPOT = 'FARGATE_SPOT',
 }
 
 /**
@@ -135,7 +149,7 @@ export interface ComputeResources {
   readonly vpcSubnets?: ec2.SubnetSelection;
 
   /**
-   * The type of compute environment: ON_DEMAND or SPOT.
+   * The type of compute environment: ON_DEMAND, SPOT, FARGATE, or FARGATE_SPOT.
    *
    * @default ON_DEMAND
    */
@@ -340,44 +354,49 @@ export class ComputeEnvironment extends Resource implements IComputeEnvironment
       physicalName: props.computeEnvironmentName,
     });
 
-    this.validateProps(props);
+    const isFargate = ComputeResourceType.FARGATE === props.computeResources?.type
+      || ComputeResourceType.FARGATE_SPOT === props.computeResources?.type;;
+
+    this.validateProps(props, isFargate);
 
     const spotFleetRole = this.getSpotFleetRole(props);
     let computeResources: CfnComputeEnvironment.ComputeResourcesProperty | undefined;
 
     // Only allow compute resources to be set when using MANAGED type
     if (props.computeResources && this.isManaged(props)) {
       computeResources = {
-        allocationStrategy: props.computeResources.allocationStrategy
-         || (
-           props.computeResources.type === ComputeResourceType.SPOT
-             ? AllocationStrategy.SPOT_CAPACITY_OPTIMIZED
-             : AllocationStrategy.BEST_FIT
-         ),
         bidPercentage: props.computeResources.bidPercentage,
         desiredvCpus: props.computeResources.desiredvCpus,
         ec2KeyPair: props.computeResources.ec2KeyPair,
         imageId: props.computeResources.image && props.computeResources.image.getImage(this).imageId,
-        instanceRole: props.computeResources.instanceRole
-          ? props.computeResources.instanceRole
-          : new iam.CfnInstanceProfile(this, 'Instance-Profile', {
-            roles: [new iam.Role(this, 'Ecs-Instance-Role', {
-              assumedBy: new iam.ServicePrincipal('ec2.amazonaws.com'),
-              managedPolicies: [
-                iam.ManagedPolicy.fromAwsManagedPolicyName('service-role/AmazonEC2ContainerServiceforEC2Role'),
-              ],
-            }).roleName],
-          }).attrArn,
-        instanceTypes: this.buildInstanceTypes(props.computeResources.instanceTypes),
         launchTemplate: props.computeResources.launchTemplate,
         maxvCpus: props.computeResources.maxvCpus || 256,
-        minvCpus: props.computeResources.minvCpus || 0,
         placementGroup: props.computeResources.placementGroup,
         securityGroupIds: this.buildSecurityGroupIds(props.computeResources.vpc, props.computeResources.securityGroups),
         spotIamFleetRole: spotFleetRole?.roleArn,
         subnets: props.computeResources.vpc.selectSubnets(props.computeResources.vpcSubnets).subnetIds,
         tags: props.computeResources.computeResourcesTags,
         type: props.computeResources.type || ComputeResourceType.ON_DEMAND,
+        ...(!isFargate ? {
+          allocationStrategy: props.computeResources.allocationStrategy
+            || (
+              props.computeResources.type === ComputeResourceType.SPOT
+                ? AllocationStrategy.SPOT_CAPACITY_OPTIMIZED
+                : AllocationStrategy.BEST_FIT
+            ),
+          instanceRole: props.computeResources.instanceRole
+            ? props.computeResources.instanceRole
+            : new iam.CfnInstanceProfile(this, 'Instance-Profile', {
+              roles: [new iam.Role(this, 'Ecs-Instance-Role', {
+                assumedBy: new iam.ServicePrincipal('ec2.amazonaws.com'),
+                managedPolicies: [
+                  iam.ManagedPolicy.fromAwsManagedPolicyName('service-role/AmazonEC2ContainerServiceforEC2Role'),
+                ],
+              }).roleName],
+            }).attrArn,
+          instanceTypes: this.buildInstanceTypes(props.computeResources.instanceTypes),
+          minvCpus: props.computeResources.minvCpus || 0,
+        } : {}),
       };
     }
 
@@ -414,7 +433,7 @@ export class ComputeEnvironment extends Resource implements IComputeEnvironment
   /**
    * Validates the properties provided for a new batch compute environment.
    */
-  private validateProps(props: ComputeEnvironmentProps) {
+  private validateProps(props: ComputeEnvironmentProps, isFargate: boolean) {
     if (props === undefined) {
       return;
     }
@@ -427,41 +446,100 @@ export class ComputeEnvironment extends Resource implements IComputeEnvironment
       throw new Error('computeResources is missing but required on a managed compute environment');
     }
 
-    // Setting a bid percentage is only allowed on SPOT resources +
-    // Cannot use SPOT_CAPACITY_OPTIMIZED when using ON_DEMAND
     if (props.computeResources) {
-      if (props.computeResources.type === ComputeResourceType.ON_DEMAND) {
-        // VALIDATE FOR ON_DEMAND
+      if (isFargate) {
+        // VALIDATE FOR FARGATE
 
-        // Bid percentage is not allowed
+        // Bid percentage cannot be set for Fargate evnvironments
         if (props.computeResources.bidPercentage !== undefined) {
-          throw new Error('Setting the bid percentage is only allowed for SPOT type resources on a batch compute environment');
+          throw new Error('Bid percentage must not be set for Fargate compute environments');
         }
 
-        // SPOT_CAPACITY_OPTIMIZED allocation is not allowed
-        if (props.computeResources.allocationStrategy && props.computeResources.allocationStrategy === AllocationStrategy.SPOT_CAPACITY_OPTIMIZED) {
-          throw new Error('The SPOT_CAPACITY_OPTIMIZED allocation strategy is only allowed if the environment is a SPOT type compute environment');
+        // Allocation strategy cannot be set for Fargate evnvironments
+        if (props.computeResources.allocationStrategy !== undefined) {
+          throw new Error('Allocation strategy must not be set for Fargate compute environments');
         }
-      } else {
-        // VALIDATE FOR SPOT
 
-        // Bid percentage must be from 0 - 100
-        if (props.computeResources.bidPercentage !== undefined &&
-          (props.computeResources.bidPercentage < 0 || props.computeResources.bidPercentage > 100)) {
-          throw new Error('Bid percentage can only be a value between 0 and 100');
+        // Desired vCPUs cannot be set for Fargate evnvironments
+        if (props.computeResources.desiredvCpus !== undefined) {
+          throw new Error('Desired vCPUs must not be set for Fargate compute environments');
         }
-      }
 
-      if (props.computeResources.minvCpus) {
-        // minvCpus cannot be less than 0
-        if (props.computeResources.minvCpus < 0) {
-          throw new Error('Minimum vCpus for a batch compute environment cannot be less than 0');
+        // Image ID cannot be set for Fargate evnvironments
+        if (props.computeResources.image !== undefined) {
+          throw new Error('Image must not be set for Fargate compute environments');
         }
 
-        // minvCpus cannot exceed max vCpus
-        if (props.computeResources.maxvCpus &&
-          props.computeResources.minvCpus > props.computeResources.maxvCpus) {
-          throw new Error('Minimum vCpus cannot be greater than the maximum vCpus');
+        // Instance types cannot be set for Fargate evnvironments
+        if (props.computeResources.instanceTypes !== undefined) {
+          throw new Error('Instance types must not be set for Fargate compute environments');
+        }
+
+        // EC2 key pair cannot be set for Fargate evnvironments
+        if (props.computeResources.ec2KeyPair !== undefined) {
+          throw new Error('EC2 key pair must not be set for Fargate compute environments');
+        }
+
+        // Instance role cannot be set for Fargate evnvironments
+        if (props.computeResources.instanceRole !== undefined) {
+          throw new Error('Instance role must not be set for Fargate compute environments');
+        }
+
+        // Launch template cannot be set for Fargate evnvironments
+        if (props.computeResources.launchTemplate !== undefined) {
+          throw new Error('Launch template must not be set for Fargate compute environments');
+        }
+
+        // Min vCPUs cannot be set for Fargate evnvironments
+        if (props.computeResources.minvCpus !== undefined) {
+          throw new Error('Min vCPUs must not be set for Fargate compute environments');
+        }
+
+        // Placement group cannot be set for Fargate evnvironments
+        if (props.computeResources.placementGroup !== undefined) {
+          throw new Error('Placement group must not be set for Fargate compute environments');
+        }
+
+        // Spot fleet role cannot be set for Fargate evnvironments
+        if (props.computeResources.spotFleetRole !== undefined) {
+          throw new Error('Spot fleet role must not be set for Fargate compute environments');
+        }
+      } else {
+        // VALIDATE FOR ON_DEMAND AND SPOT
+        if (props.computeResources.minvCpus) {
+          // minvCpus cannot be less than 0
+          if (props.computeResources.minvCpus < 0) {
+            throw new Error('Minimum vCpus for a batch compute environment cannot be less than 0');
+          }
+
+          // minvCpus cannot exceed max vCpus
+          if (props.computeResources.maxvCpus &&
+            props.computeResources.minvCpus > props.computeResources.maxvCpus) {
+            throw new Error('Minimum vCpus cannot be greater than the maximum vCpus');
+          }
+        }
+        // Setting a bid percentage is only allowed on SPOT resources +
+        // Cannot use SPOT_CAPACITY_OPTIMIZED when using ON_DEMAND
+        if (props.computeResources.type === ComputeResourceType.ON_DEMAND) {
+          // VALIDATE FOR ON_DEMAND
+
+          // Bid percentage is not allowed
+          if (props.computeResources.bidPercentage !== undefined) {
+            throw new Error('Setting the bid percentage is only allowed for SPOT type resources on a batch compute environment');
+          }
+
+          // SPOT_CAPACITY_OPTIMIZED allocation is not allowed
+          if (props.computeResources.allocationStrategy && props.computeResources.allocationStrategy === AllocationStrategy.SPOT_CAPACITY_OPTIMIZED) {
+            throw new Error('The SPOT_CAPACITY_OPTIMIZED allocation strategy is only allowed if the environment is a SPOT type compute environment');
+          }
+        } else if (props.computeResources.type === ComputeResourceType.SPOT) {
+          // VALIDATE FOR SPOT
+
+          // Bid percentage must be from 0 - 100
+          if (props.computeResources.bidPercentage !== undefined &&
+            (props.computeResources.bidPercentage < 0 || props.computeResources.bidPercentage > 100)) {
+            throw new Error('Bid percentage can only be a value between 0 and 100');
+          }
         }
       }
     }