content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License. You may obtain a copy of the License at
   *
   *    http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.kafka.clients;
  
  import org.apache.kafka.common.config.ConfigException;
  
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.MethodSource;
  import org.mockito.MockedConstruction;
  import org.mockito.MockedStatic;
  
  import java.net.InetAddress;
  import java.net.InetSocketAddress;
  import java.net.UnknownHostException;
  import java.util.Collections;
  import java.util.List;
  import java.util.stream.Stream;
  
  import static java.util.Arrays.asList;
  import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.mockito.Mockito.mock;
  import static org.mockito.Mockito.mockConstruction;
  import static org.mockito.Mockito.mockStatic;
  import static org.mockito.Mockito.when;
  
  public class ClientUtilsTest {
  
      @Test
      public void testParseAndValidateAddresses() {
          checkWithoutLookup("127.0.0.1:8000");
          checkWithoutLookup("localhost:8080");
          checkWithoutLookup("[::1]:8000");
          checkWithoutLookup("[2001:db8:85a3:8d3:1319:8a2e:370:7348]:1234", "localhost:10000");
          List<InetSocketAddress> validatedAddresses = checkWithoutLookup("localhost:10000");
          assertEquals(1, validatedAddresses.size());
          InetSocketAddress onlyAddress = validatedAddresses.get(0);
          assertEquals("localhost", onlyAddress.getHostName());
          assertEquals(10000, onlyAddress.getPort());
      }
  
      @Test
      public void testParseAndValidateAddressesWithReverseLookup() {
          checkWithoutLookup("127.0.0.1:8000");
          checkWithoutLookup("localhost:8080");
          checkWithoutLookup("[::1]:8000");
          checkWithoutLookup("[2001:db8:85a3:8d3:1319:8a2e:370:7348]:1234", "localhost:10000");
  
          String hostname = "example.com";
          Integer port = 10000;
          String canonicalHostname1 = "canonical_hostname1";
          String canonicalHostname2 = "canonical_hostname2";
          try (final MockedStatic<InetAddress> inetAddress = mockStatic(InetAddress.class)) {
              InetAddress inetAddress1 = mock(InetAddress.class);
              when(inetAddress1.getCanonicalHostName()).thenReturn(canonicalHostname1);
              InetAddress inetAddress2 = mock(InetAddress.class);
              when(inetAddress2.getCanonicalHostName()).thenReturn(canonicalHostname2);
              inetAddress.when(() -> InetAddress.getAllByName(hostname))
                  .thenReturn(new InetAddress[]{inetAddress1, inetAddress2});
              try (MockedConstruction<InetSocketAddress> inetSocketAddress =
                       mockConstruction(
                           InetSocketAddress.class,
                           (mock, context) -> {
                               when(mock.isUnresolved()).thenReturn(false);
                               when(mock.getHostName()).thenReturn((String) context.arguments().get(0));
                               when(mock.getPort()).thenReturn((Integer) context.arguments().get(1));
                           })
              ) {
                  List<InetSocketAddress> validatedAddresses = checkWithLookup(Collections.singletonList(hostname + ":" + port));
                  assertEquals(2, inetSocketAddress.constructed().size());
                  assertEquals(2, validatedAddresses.size());
                  assertTrue(validatedAddresses.containsAll(List.of(
                      inetSocketAddress.constructed().get(0),
                      inetSocketAddress.constructed().get(1)))
                  );
                  validatedAddresses.forEach(address -> assertEquals(port, address.getPort()));
                  validatedAddresses.stream().map(InetSocketAddress::getHostName).forEach(
                      hostName -> assertTrue(List.of(canonicalHostname1, canonicalHostname2).contains(hostName))
                  );
              }
          }
      }
  
      @Test
      public void testValidBrokerAddress() {
          List<String> validBrokerAddress = List.of("localhost:9997", "localhost:9998", "localhost:9999");
          assertDoesNotThrow(() -> ClientUtils.parseAndValidateAddresses(validBrokerAddress, ClientDnsLookup.USE_ALL_DNS_IPS));
      }
  
      static Stream<List<String>> provideInvalidBrokerAddressTestCases() {
          return Stream.of(
              List.of("localhost:9997\nlocalhost:9998\nlocalhost:9999"),
              List.of("localhost:9997", "localhost:9998", " localhost:9999"),
              // Intentionally provide a single string, as users may provide space-separated brokers, which will be parsed as a single string.
              List.of("localhost:9997 localhost:9998 localhost:9999")
          );
      }
  
      @ParameterizedTest
      @MethodSource("provideInvalidBrokerAddressTestCases")
      public void testInvalidBrokerAddress(List<String> addresses) {
          assertThrows(ConfigException.class,
              () -> ClientUtils.parseAndValidateAddresses(addresses, ClientDnsLookup.USE_ALL_DNS_IPS));
      }
  
      @Test
      public void testInvalidConfig() {
          assertThrows(IllegalArgumentException.class,
              () -> ClientUtils.parseAndValidateAddresses(Collections.singletonList("localhost:10000"), "random.value"));
      }
  
      @Test
      public void testNoPort() {
          assertThrows(ConfigException.class, () -> checkWithoutLookup("127.0.0.1"));
      }
  
      @Test
      public void testInvalidPort() {
          assertThrows(ConfigException.class, () -> checkWithoutLookup("localhost:70000"));
      }
  
      @Test
      public void testOnlyBadHostname() {
          try (MockedConstruction<InetSocketAddress> inetSocketAddress =
                   mockConstruction(
                       InetSocketAddress.class,
                       (mock, context) -> when(mock.isUnresolved()).thenReturn(true)
                   )
          ) {
              Exception exception = assertThrows(
                  ConfigException.class,
                  () -> checkWithoutLookup("some.invalid.hostname.foo.bar.local:9999")
              );
              assertEquals(
                  "No resolvable bootstrap urls given in " + CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG,
                  exception.getMessage()
              );
          }
      }
  
      @Test
      public void testFilterPreferredAddresses() throws UnknownHostException {
          InetAddress ipv4 = InetAddress.getByName("192.0.0.1");
          InetAddress ipv6 = InetAddress.getByName("::1");
  
          InetAddress[] ipv4First = new InetAddress[]{ipv4, ipv6, ipv4};
          List<InetAddress> result = ClientUtils.filterPreferredAddresses(ipv4First);
          assertTrue(result.contains(ipv4));
          assertFalse(result.contains(ipv6));
          assertEquals(2, result.size());
  
          InetAddress[] ipv6First = new InetAddress[]{ipv6, ipv4, ipv4};
          result = ClientUtils.filterPreferredAddresses(ipv6First);
          assertTrue(result.contains(ipv6));
          assertFalse(result.contains(ipv4));
          assertEquals(1, result.size());
      }
  
      @Test
      public void testResolveUnknownHostException() {
          HostResolver throwingHostResolver = host -> {
              throw new UnknownHostException();
          };
          assertThrows(
              UnknownHostException.class,
              () -> ClientUtils.resolve("some.invalid.hostname.foo.bar.local", throwingHostResolver)
          );
      }
  
      @Test
      public void testResolveDnsLookup() throws UnknownHostException {
          InetAddress[] addresses = new InetAddress[] {
              InetAddress.getByName("198.51.100.0"), InetAddress.getByName("198.51.100.5")
          };
          HostResolver hostResolver = new AddressChangeHostResolver(addresses, addresses);
          assertEquals(asList(addresses), ClientUtils.resolve("kafka.apache.org", hostResolver));
      }
  
      private List<InetSocketAddress> checkWithoutLookup(String... url) {
          return ClientUtils.parseAndValidateAddresses(asList(url), ClientDnsLookup.USE_ALL_DNS_IPS);
      }
  
      private List<InetSocketAddress> checkWithLookup(List<String> url) {
          return ClientUtils.parseAndValidateAddresses(url, ClientDnsLookup.RESOLVE_CANONICAL_BOOTSTRAP_SERVERS_ONLY);
      }
  }
  