[cognito] can't add cognito trigger after UserPool.fromUserPoolId

version:

"@aws-cdk/aws-cognito": "^1.60.0",

Code

    const amplifyUserPool = cognito.UserPool.fromUserPoolId(
      this,
      "amplifyUserPool",
      "us-east-1_ABCDE"
    );

    console.log("addTrigger" in amplifyUserPool);

Expect

true

Receive

false

Documentation

Importing User Pools addTrigger

More

The documentation indeed mentions:

However, imported user pools have limited configurability. As a rule of thumb, none of the properties that is are part of the AWS::Cognito::UserPool CloudFormation resource can be configured.

But I am when I am using serverless framework, it works like a charm. Just wonder any workarounds against this? I want to move my full serverless stack to CDK, it is such a beautiful tech.

• There is a stackoverflow question against this: https://stackoverflow.com/questions/61816264/add-lambda-trigger-to-imported-cognito-user-pool-with-aws-cdk

[cstst]

I was not able to get the above solution working as I did not have access to the underlying CfnUserPool via fromUserPoolId or node.defaultChild.

I was however able to add triggers to a user pool imported via fromUserPoolId by using a custom resource:

    const userPool = Cognito.UserPool.fromUserPoolId(this, "UserPool", userPoolId);

    new CustomResources.AwsCustomResource(this, "UpdateUserPool", {
      resourceType: "Custom::UpdateUserPool",
      onCreate: {
        region: this.region,
        service: "CognitoIdentityServiceProvider",
        action: "updateUserPool",
        parameters: {
          UserPoolId: userPool.userPoolId,
          LambdaConfig: {
            PreSignUp: preSignUpHandler.functionArn,
            DefineAuthChallenge: defineAuthChallengeHandler.functionArn,
            CreateAuthChallenge: createAuthChallengeHandler.functionArn,
            VerifyAuthChallengeResponse: verifyAuthChallengeResponseHandler.functionArn,
          },
        },
        physicalResourceId: CustomResources.PhysicalResourceId.of(userPool.userPoolId),
      },
      policy: CustomResources.AwsCustomResourcePolicy.fromSdkCalls({ resources: CustomResources.AwsCustomResourcePolicy.ANY_RESOURCE }),
    });

[brianium]

@skinny85 that worked a treat! Thank you so much 🙇🏻

For anyone else encountering this issue, the solution looks like this:

const cfnPool = template.getResource("UserPool") as cognito.CfnUserPool;
cfnPool.lambdaConfig = {
  userMigration: migrate.functionArn,
};