Merge branch 'master' into patch-3

.mergify.yml

@@ -56,9 +56,17 @@ pull_request_rules:
       - status-success~=AWS CodeBuild us-east-1
       - status-success=Semantic Pull Request
       - status-success=mandatory-changes
+  - name: when changes are requested
+    actions:
+      comment:
+        message: Once all the requested changes have been addressed, and the PR is ready for another review, remember to [dismiss the review](https://help.github.com/en/github/collaborating-with-issues-and-pull-requests/dismissing-a-pull-request-review).
+    conditions:
+      - changes-requested-reviews-by=@aws/aws-cdk-team
   - name: remove stale reviews
     actions:
-      dismiss_reviews: {}
+      dismiss_reviews:
+        approved: true
+        changes_requested: false
     conditions:
       - author!=dependabot[bot]
       - author!=dependabot-preview[bot]

packages/@aws-cdk/aws-appsync/test/integ.graphql.expected.json

@@ -45,7 +45,6 @@
         },
         "EmailVerificationMessage": "Hello {username}, Your verification code is {####}",
         "EmailVerificationSubject": "Verify your new account",
-        "LambdaConfig": {},
         "SmsConfiguration": {
           "ExternalId": "awsappsyncintegPool5D14B05B",
           "SnsCallerArn": {
@@ -606,4 +605,4 @@
       "DeletionPolicy": "Delete"
     }
   }
-}
+}

packages/@aws-cdk/aws-codebuild/lib/project.ts

@@ -1198,9 +1198,13 @@ export class LinuxBuildImage implements IBuildImage {
   public static readonly STANDARD_1_0 = LinuxBuildImage.codeBuildImage('aws/codebuild/standard:1.0');
   public static readonly STANDARD_2_0 = LinuxBuildImage.codeBuildImage('aws/codebuild/standard:2.0');
   public static readonly STANDARD_3_0 = LinuxBuildImage.codeBuildImage('aws/codebuild/standard:3.0');
+  /** The `aws/codebuild/standard:4.0` build image. */
+  public static readonly STANDARD_4_0 = LinuxBuildImage.codeBuildImage('aws/codebuild/standard:4.0');
 
   public static readonly AMAZON_LINUX_2 = LinuxBuildImage.codeBuildImage('aws/codebuild/amazonlinux2-x86_64-standard:1.0');
   public static readonly AMAZON_LINUX_2_2 = LinuxBuildImage.codeBuildImage('aws/codebuild/amazonlinux2-x86_64-standard:2.0');
+  /** The Amazon Linux 2 x86_64 standard image, version `3.0`. */
+  public static readonly AMAZON_LINUX_2_3 = LinuxBuildImage.codeBuildImage('aws/codebuild/amazonlinux2-x86_64-standard:3.0');
 
   public static readonly AMAZON_LINUX_2_ARM: IBuildImage = new ArmBuildImage('aws/codebuild/amazonlinux2-aarch64-standard:1.0');
 

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

@@ -38,6 +38,7 @@ This module is part of the [AWS Cloud Development Kit](https://github.com/aws/aw
   - [Security](#security)
     - [Multi-factor Authentication](#multi-factor-authentication-mfa)
   - [Emails](#emails)
+  - [Lambda Triggers](#lambda-triggers)
   - [Import](#importing-user-pools)
 
 ## User Pools
@@ -277,6 +278,38 @@ Amazon SES, however, support for Amazon SES is not available in the CDK yet. If
 give [this issue](https://github.com/aws/aws-cdk/issues/6768) a +1. Until then, you can use the [cfn
 layer](https://docs.aws.amazon.com/cdk/latest/guide/cfn_layer.html) to configure this.
 
+### Lambda Triggers
+
+User pools can be configured such that AWS Lambda functions can be triggered when certain user operations or actions
+occur, such as, sign up, user confirmation, sign in, etc. They can also be used to add custom authentication
+challenges, user migrations and custom verification messages. Learn more about triggers at [User Pool Workflows with
+Triggers](https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html).
+
+Lambda triggers can either be specified as part of the `UserPool` initialization, or it can be added later, via methods
+on the construct, as so -
+
+```ts
+const authChallengeFn = new lambda.Function(this, 'authChallengeFn', {
+  // ...
+});
+
+const userpool = new UserPool(this, 'myuserpool', {
+  // ...
+  triggers: {
+    createAuthChallenge: authChallengeFn,
+    // ...
+  }
+});
+
+userpool.addTrigger(UserPoolOperation.USER_MIGRATION, new lambda.Function(this, 'userMigrationFn', {
+  // ...
+}));
+```
+
+The following table lists the set of triggers available, and their corresponding method to add it to the user pool.
+For more information on the function of these triggers and how to configure them, read [User Pool Workflows with
+Triggers](https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html).
+
 ### Importing User Pools
 
 Any user pool that has been created outside of this stack, can be imported into the CDK app. Importing a user pool