src/main/java/net/hostsharing/hsadminng/hs/hosting/asset/validators/Dns.java

@@ -4,6 +4,7 @@ import org.apache.commons.collections4.EnumerationUtils;
 
 import javax.naming.InvalidNameException;
 import javax.naming.NameNotFoundException;
+import javax.naming.NamingEnumeration;
 import javax.naming.NamingException;
 import javax.naming.ServiceUnavailableException;
 import javax.naming.directory.Attribute;
@@ -23,7 +24,6 @@ public class Dns {
 
     public enum Status {
         SUCCESS,
-        RECORD_TYPE_NOT_FOUND,
         NAME_NOT_FOUND,
         INVALID_NAME,
         SERVICE_UNAVAILABLE,
@@ -31,6 +31,22 @@ public class Dns {
     }
 
     public record Result(Status status, List<String> records, NamingException exception) {
+
+        public static Result fromRecords(final NamingEnumeration<?> enumeration) {
+            final List<String> records = enumeration == null
+                    ? emptyList()
+                    : EnumerationUtils.toList(enumeration).stream().map(Object::toString).toList();
+            return new Result(Status.SUCCESS, records, null);
+        }
+
+        public static Result fromException(final NamingException exception) {
+            return switch (exception) {
+                case ServiceUnavailableException exc -> new Result(Status.SERVICE_UNAVAILABLE, null, exc);
+                case NameNotFoundException exc -> new Result(Status.NAME_NOT_FOUND, null, exc);
+                case InvalidNameException exc -> new Result(Status.INVALID_NAME, null, exc);
+                case NamingException exc -> new Result(Status.UNKNOWN_FAILURE, null, exc);
+            };
+        }
     }
 
     private final String domainName;
@@ -51,23 +67,12 @@ public class Dns {
         try {
             final var env = new Hashtable<>();
             env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
-            final Attribute r = new InitialDirContext(env)
+            final Attribute records = new InitialDirContext(env)
                     .getAttributes(domainName, new String[] { recordType })
                     .get(recordType);
-            return new Result(
-                r == null ? Status.RECORD_TYPE_NOT_FOUND : Status.SUCCESS,
-                r == null
-                    ? emptyList()
-                    : EnumerationUtils.toList(r.getAll()).stream().map(Object::toString).toList(),
-                null);
-        } catch (final ServiceUnavailableException e) {
-            return new Result(Status.SERVICE_UNAVAILABLE, null, e);
-        } catch (final NameNotFoundException e) {
-            return new Result(Status.NAME_NOT_FOUND, null, e);
-        } catch (InvalidNameException e) {
-            return new Result(Status.INVALID_NAME, null, e);
-        } catch (NamingException e) {
-            return new Result(Status.UNKNOWN_FAILURE, null, e);
+            return Result.fromRecords(records != null ? records.getAll() : null);
+        } catch (final NamingException exception) {
+            return Result.fromException(exception);
         }
     }
 

src/main/java/net/hostsharing/hsadminng/hs/hosting/asset/validators/HsDomainSetupHostingAssetValidator.java

@@ -54,12 +54,9 @@ class HsDomainSetupHostingAssetValidator extends HostingAssetEntityValidator {
                 if (found.isPresent()) {
                     break;
                 }
-            case Dns.Status.RECORD_TYPE_NOT_FOUND:
-                violations.add("Domain " + assetEntity.getIdentifier() + " exists, but no record 'TXT Hostsharing-domain-setup-challenge:FIXME' found ");
-                break;
 
             case Dns.Status.NAME_NOT_FOUND:
-                // no DNS verification necessary
+                // no DNS verification necessary / FIXME: at least if the superdomain is at registrar level
                 break;
 
             case Dns.Status.INVALID_NAME:

src/test/java/net/hostsharing/hsadminng/hs/hosting/asset/validators/HsDomainSetupHostingAssetValidatorUnitTest.java

@@ -9,6 +9,10 @@ import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.EnumSource;
 import org.junit.jupiter.params.provider.ValueSource;
 
+import javax.naming.InvalidNameException;
+import javax.naming.NameNotFoundException;
+import javax.naming.NamingException;
+import javax.naming.ServiceUnavailableException;
 import java.util.Map;
 
 import static net.hostsharing.hsadminng.hs.hosting.asset.HsHostingAssetType.CLOUD_SERVER;
@@ -176,6 +180,49 @@ class HsDomainSetupHostingAssetValidatorUnitTest {
         assertThat(result).isEmpty();
     }
 
+    enum DnsLookupFailureTestCase {
+        SERVICE_UNAVAILABLE(
+                new ServiceUnavailableException("no Internet connection"),
+                "DNS request for example.org failed: javax.naming.ServiceUnavailableException: no Internet connection"),
+        NAME_NOT_FOUND(
+                new NameNotFoundException("domain not registered"),
+                null), // no
+        INVALID_NAME(
+                new InvalidNameException("domain name too long or whatever"),
+                "Invalid domain name example.org"),
+        UNKNOWN_FAILURE(
+                new NamingException("some other problem"),
+                "DNS request for example.org failed: javax.naming.NamingException: some other problem");
+
+        public final NamingException givenException;
+        public final String expectedErrorMessage;
+
+        DnsLookupFailureTestCase(final NamingException givenException, final String expectedErrorMessage) {
+            this.givenException = givenException;
+            this.expectedErrorMessage = expectedErrorMessage;
+        }
+    }
+
+    @ParameterizedTest
+    @EnumSource(DnsLookupFailureTestCase.class)
+    void handlesDnsLookupFailures(final DnsLookupFailureTestCase testCase) {
+
+        // given
+        Dns.fakeNextResult(Dns.Result.fromException(testCase.givenException));
+        final var domainSetupHostingAssetEntity = validEntityBuilder().build();
+        final var validator = HostingAssetEntityValidatorRegistry.forType(domainSetupHostingAssetEntity.getType());
+
+        // when
+        final var result = validator.validateEntity(domainSetupHostingAssetEntity);
+
+        // then
+        if (testCase.expectedErrorMessage != null) {
+            assertThat(result).containsExactly(testCase.expectedErrorMessage);
+        } else {
+            assertThat(result).isEmpty();
+        }
+    }
+
     private static HsHostingAssetRealEntity createValidParentDomainSetupAsset(final String parentDomainName) {
         final var bookingItem = HsBookingItemRealEntity.builder()
                 .type(HsBookingItemType.DOMAIN_SETUP)