feat(cdk): add the CodeDeployLambdaAlias Update Policy. (#1346)

Fixes #1177.

Author: skinny85

packages/@aws-cdk/cdk/lib/cloudformation/resource-policy.ts

@@ -124,6 +124,12 @@ export interface UpdatePolicy {
    */
   autoScalingScheduledAction?: AutoScalingScheduledAction;
 
+  /**
+   * To perform an AWS CodeDeploy deployment when the version changes on an AWS::Lambda::Alias resource,
+   * use the CodeDeployLambdaAliasUpdate update policy.
+   */
+  codeDeployLambdaAliasUpdate?: CodeDeployLambdaAliasUpdate;
+
   /**
    * To modify a replication group's shards by adding or removing shards, rather than replacing the entire
    * AWS::ElastiCache::ReplicationGroup resource, use the UseOnlineResharding update policy.
@@ -236,3 +242,29 @@ export interface AutoScalingScheduledAction {
   */
   ignoreUnmodifiedGroupSizeProperties?: boolean;
 }
+
+/**
+ * To perform an AWS CodeDeploy deployment when the version changes on an AWS::Lambda::Alias resource,
+ * use the CodeDeployLambdaAliasUpdate update policy.
+ */
+export interface CodeDeployLambdaAliasUpdate {
+  /**
+   * The name of the AWS CodeDeploy application.
+   */
+  applicationName: string;
+
+  /**
+   * The name of the AWS CodeDeploy deployment group. This is where the traffic-shifting policy is set.
+   */
+  deploymentGroupName: string;
+
+  /**
+   * The name of the Lambda function to run before traffic routing starts.
+   */
+  beforeAllowTrafficHook?: string;
+
+  /**
+   * The name of the Lambda function to run after traffic routing completes.
+   */
+  afterAllowTrafficHook?: string;
+}

packages/@aws-cdk/cdk/test/cloudformation/test.resource.ts

@@ -171,7 +171,15 @@ export = {
 
     r1.options.creationPolicy = { autoScalingCreationPolicy: { minSuccessfulInstancesPercent: 10 } };
     // tslint:disable-next-line:max-line-length
-    r1.options.updatePolicy = { autoScalingScheduledAction: { ignoreUnmodifiedGroupSizeProperties: false }, autoScalingReplacingUpdate: { willReplace: true }};
+    r1.options.updatePolicy = {
+      autoScalingScheduledAction: { ignoreUnmodifiedGroupSizeProperties: false },
+      autoScalingReplacingUpdate: { willReplace: true },
+      codeDeployLambdaAliasUpdate: {
+        applicationName: 'CodeDeployApplication',
+        deploymentGroupName: 'CodeDeployDeploymentGroup',
+        beforeAllowTrafficHook: 'lambda1',
+      },
+    };
     r1.options.deletionPolicy = DeletionPolicy.Retain;
 
     test.deepEqual(stack.toCloudFormation(), {
@@ -182,6 +190,11 @@ export = {
           UpdatePolicy: {
             AutoScalingScheduledAction: { IgnoreUnmodifiedGroupSizeProperties: false },
             AutoScalingReplacingUpdate: { WillReplace: true },
+            CodeDeployLambdaAliasUpdate: {
+              ApplicationName: 'CodeDeployApplication',
+              DeploymentGroupName: 'CodeDeployDeploymentGroup',
+              BeforeAllowTrafficHook: 'lambda1',
+            },
           },
           DeletionPolicy: 'Retain'
         }