How to reference Cognito UserPoolDomain alias target within CloudFormation template? - amazon-web-services

Question

I want to create A record for Cognito UserPoolDomain alias target (Cognito auto-generated Cloudfront distribution) within CloudFormation template.
I didn't find in docs how to reference alias target of UserPoolDomain?
Should I create a Cloudfront distribution and then somehow pass it to Cognito?
This is snippet of my CloudFormation template and what I try to achieve:
...
AuthUserPoolDomain:
Type: AWS::Cognito::UserPoolDomain
Properties:
UserPoolId: !Ref AuthUserPool
Domain: auth.example.com
CustomDomainConfig:
CertificateArn: !Ref CertificateArn
AuthRecordSets:
Type: AWS::Route53::RecordSetGroup
Properties:
HostedZoneName: example.com.
RecordSets:
- Name: auth.example.com
Type: A
AliasTarget:
DNSName: ???
EvaluateTargetHealth: false
HostedZoneId: Z2FDTNDATAQYW2 # This is always the hosted zone ID when you create an alias record that routes traffic to a CloudFront distribution.
...
Please help!

Answer 1

As a workaround solution I've created a new CloudFormation template that accept Cognito target alias as a parameter (CognitoDistribution).
After Cognitio UserPoolDoman is created I run this to find distribution
aws cognito-idp describe-user-pool-domain --domain auth.example.com \
| jq -r '.DomainDescription.CloudFrontDistribution'
and then I create DNS record with this template
AWSTemplateFormatVersion: 2010-09-09
Description: >-
Add CNAME record for Cognito UserPoolDomain alias target (CloudFront distribution).
It is not part of same template as AWS::Cognito::UserPoolDomain because UserPoolDomain does not return distribution ref.
Parameters:
HostedZoneName:
Type: String
UserPoolDomain:
Type: String
CognitoTargetAlias:
Type: String
Resources:
AuthRecordSets:
Type: AWS::Route53::RecordSetGroup
Properties:
HostedZoneName: !Sub "${HostedZoneName}."
RecordSets:
- Name: !Ref UserPoolDomain
Type: A
AliasTarget:
DNSName: !Ref CognitoTargetAlias
EvaluateTargetHealth: false
# This is always the hosted zone ID when you create an alias record that routes traffic to a CloudFront distribution.
HostedZoneId: Z2FDTNDATAQYW2
not clean solution but at least I don't need to do it in console