Cloud Run FunctionsでサーバレスVPCアクセスコネクタ経由でCloud DNSの限定公開のプライベートゾーンのレコードを解決できるか試してみた

resource "google_compute_subnetwork" "vpc_connector_subnet" {
  name          = "vpc-connector-subnetwork"
  ip_cidr_range = "192.0.0.0/28"
  region        = "asia-northeast1"
  network       = "default"
}
resource "google_vpc_access_connector" "connector" {
  name          = "vpc-connector"
  min_instances = 2
  max_instances = 3
  subnet {
    name = google_compute_subnetwork.vpc_connector_subnet.name
  }
}

provider "google" {
  project = "プロジェクト名"
  region  = "asia-northeast1"
}

terraform {
  required_version = "1.10.3"

  required_providers {
    google = {
      source = "hashicorp/google"
      # provider version
      version = "~> 5.0"
    }
  }
}

resource "google_cloudfunctions2_function" "function" {
  name = "dns-query-test"
  location = "asia-northeast1"
  description = "dns query test"
  build_config {
    runtime = "python312"
    entry_point = "dns_test"
    source {
      storage_source {
        bucket = "バケット名"
        object = "zipファイル名"
      }
    }
  }

  service_config {
    max_instance_count  = 1
    available_memory    = "256M"
    timeout_seconds     = 60
    vpc_connector       = "サーバレスVPCアクセスコネクタ名"
  }
}

iimport functions_framework
import dns.resolver

@functions_framework.http
def dns_test(request):
    domain = "限定公開プライベートゾーンのDNS名を指定"
    try:
        # CNAMEレコードを取得
        cname_answers = dns.resolver.resolve(domain, 'CNAME')
        for cname_rdata in cname_answers:
            cname_target = cname_rdata.target.to_text()
            print(f"CNAME Record: {domain} -> {cname_target}")

            # CNAMEの先のAレコードを取得
            a_answers = dns.resolver.resolve(cname_target, 'A')

            # Aレコードの値をリストに収集
            a_records = [a_rdata.to_text() for a_rdata in a_answers]
            print(f"A Records for {cname_target}: {a_records}")

            # Aレコードをレスポンスとして返す
            return {
                "domain": domain,
                "cname_target": cname_target,
                "a_records": a_records
            }

    except dns.resolver.NXDOMAIN:
        # ドメインが存在しない場合
        return 'Domain does not exist.', 404

    except dns.exception.Timeout:
        # DNSクエリがタイムアウトした場合
        return 'DNS query timed out.', 504

    except Exception as e:
        # その他のエラー
        return f'An error occurred: {str(e)}', 500

functions-framework==3.*
dnspython

{"a_records":["***.***.***.***"],"cname_target":"公開ゾーンのドメイン名.","domain":"限定公開ゾーンのドメイン名"}

  service_config {
    max_instance_count  = 1
    available_memory    = "256M"
    timeout_seconds     = 60
    #vpc_connector       = "サーバレスVPCアクセスコネクタ名"
  }

Domain does not exist.

    except dns.resolver.NXDOMAIN:
        # ドメインが存在しない場合
        return 'Domain does not exist.', 404