I’m not sure if this is a bug or if I am doing something wrong but I keep getting this exception when I try to attach a custom domain to my API gateway:

3:28:13 p.m. | CREATE_FAILED | AWS::ApiGatewayV2::ApiMapping
| API/Default…DomainName$default Resource handler returned message:
“Invalid domain name identifier specified (Service:
AmazonApiGatewayV2; Status Code: 404; Error Code: NotFoundException;
Request ID: ; Proxy: null)” (RequestToken: ,
HandlerErrorCode: GeneralServiceException)

Here is my code:

export class APIStack extends Stack {
  constructor(scope: Construct, id: string, props: APIStackProps) {
    super(scope, id, props);

    // Custom Domain
    const apiDomainName = `api.${props.appName}.${props.rootDomain}`;

    const hostedZone = HostedZone.fromLookup(this, "HostedZone", {
      domainName: props.rootDomain,
    });

    const domainCertificate = new Certificate(
      this,
      `${props.appName}-Certificate`,
      {
        domainName: apiDomainName,
        certificateName: `${props.appName}-Certificate`,
        validation: CertificateValidation.fromDns(hostedZone),
      }
    );

    // Custom domain for API
    const gatewayDomain = new DomainName(this, `${props.appName}-DomainName`, {
      domainName: apiDomainName,
      certificate: domainCertificate,
      endpointType: EndpointType.REGIONAL,
    });

    // Security
    const apiAuthorizer = new HttpUserPoolAuthorizer(
      `${props.appName}-APIAuthorizer`,
      props.userPool,
      { userPoolClients: [props.appClient] }
    );

    // API
    const httpApi = new HttpApi(this, `${props.appName}-API`, {
      defaultAuthorizer: apiAuthorizer,
      defaultDomainMapping: {
        domainName: gatewayDomain,
        mappingKey: "$default",
      },
    });

    new ApiMapping(this, "Mapping", {
      domainName: gatewayDomain,
      api: httpApi,
    });

    // route53 records
    new ARecord(this, `${props.appName}-AliasRecord`, {
      zone: hostedZone,
      recordName: apiDomainName,
      target: RecordTarget.fromAlias(
        new ApiGatewayv2DomainProperties(
          gatewayDomain.regionalDomainName,
          gatewayDomain.regionalHostedZoneId
        )
      ),
    });

    // Lambdas
    const testLambda = new NodejsFunction(this, `${props.appName}-TestLambda`, {
      runtime: Runtime.NODEJS_20_X,
      handler: "handler",
      functionName: `${props.appName}-test-function`,
      entry: path.join(__dirname, "../lambdas/endpoints/test", "index.ts"),
    });

    // Registering routes
    const testLambdaIntegration = new HttpLambdaIntegration(
      "TestLambdaIntegration",
      testLambda
    );

    httpApi.addRoutes({
      path: "/test",
      methods: [HttpMethod.GET],
      integration: testLambdaIntegration,
      authorizer: apiAuthorizer,
    });
  }
}

The error occurs when I create the ApiMapping and, from what I can tell, CloudFormation is trying to create the mapping before the domain for the API Gateway (gatewayDomain) has been created and propogated. I’ve tried explicitly adding a dependency to create the domain before creating the mapping, but it still does not work:

apiMapping.node.addDependency(gatewayDomain)

I have found that creating the mapping using the console, or using the aws cli works but I’d like to use the cdk for this. Any help would be appreciate 🙂