api-domain.template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Description: >-
  Creates a custom domain for API Gateway.

Parameters:
  ApiDomain:
    Type: String
    Description: Full domain for the API Gateway custom domain that you want to create.
  CertificateArn:
    Type: String
    Description: Certificate Manager ARN for the ApiDomain certificate. Required to use a custom domain.
  HostedZoneId:
    Type: String
    Description: If provided, creates a record set group connecting the custom domain to a Route53 zone.
    Default: ''
  HostedZoneName:
    Type: String
    Description: Can provide this as an alternative to HostedZoneId
    Default: ''

Conditions:
  HasHostedZoneId: !Not [!Equals [!Ref HostedZoneId, '']]
  HasHostedZoneName: !Not [!Equals [!Ref HostedZoneName, '']]
  CreateRecordSetGroup: !Or
    - !Condition HasHostedZoneId
    - !Condition HasHostedZoneName

Resources:
  CustomDomain:
    Type: AWS::ApiGatewayV2::DomainName
    Properties:
      DomainName: !Ref ApiDomain
      DomainNameConfigurations:
        - CertificateArn: !Ref CertificateArn
          SecurityPolicy: TLS_1_2

  RecordSetGroup:
    Type: AWS::Route53::RecordSetGroup
    Condition: CreateRecordSetGroup
    Properties: !If
      - HasHostedZoneId
      - HostedZoneId: !Ref HostedZoneId
        RecordSets:
          - Name: !Ref CustomDomain
            Type: A
            AliasTarget:
              HostedZoneId: !GetAtt CustomDomain.RegionalHostedZoneId
              DNSName: !GetAtt CustomDomain.RegionalDomainName
      - HostedZoneName: !Ref HostedZoneName
        RecordSets:
          - Name: !Ref CustomDomain
            Type: A
            AliasTarget:
              HostedZoneId: !GetAtt CustomDomain.RegionalHostedZoneId
              DNSName: !GetAtt CustomDomain.RegionalDomainName

Outputs:
  CustomDomain:
    Value: !Ref CustomDomain
  CertificateArn:
    Value: !Ref CertificateArn