Improve default dns client configuration - fixes #2303

eclipse-vertx · Jan 30, 2018 · df533fc · df533fc
1 parent 13e9512
commit df533fc
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Showing 3 changed files with 28 additions and 11 deletions.
diff --git a/src/main/java/io/vertx/core/dns/DnsClientOptions.java b/src/main/java/io/vertx/core/dns/DnsClientOptions.java
@@ -12,6 +12,7 @@
 package io.vertx.core.dns;
 
 import io.vertx.codegen.annotations.DataObject;
+import io.vertx.core.VertxOptions;
 import io.vertx.core.json.JsonObject;
 
 /**
@@ -23,17 +24,17 @@
 public class DnsClientOptions {
 
   /**
-   * The default value for the port = 53
+   * The default value for the port = {@code -1} (configured by {@link VertxOptions#getAddressResolverOptions()})
    */
-  public static final int DEFAULT_PORT = 53;
+  public static final int DEFAULT_PORT = -1;
 
   /**
-   * The default value for the host = localhost
+   * The default value for the host = {@code null} (configured by {@link VertxOptions#getAddressResolverOptions()})
    */
-  public static final String DEFAULT_HOST = "localhost";
+  public static final String DEFAULT_HOST = null;
 
   /**
-   * The default value for the query timeout in millis = 5000
+   * The default value for the query timeout in millis = {@code 5000}
    */
   public static final long DEFAULT_QUERY_TIMEOUT = 5000;
 

diff --git a/src/main/java/io/vertx/core/impl/VertxImpl.java b/src/main/java/io/vertx/core/impl/VertxImpl.java
@@ -410,14 +410,20 @@ public DnsClient createDnsClient(int port, String host) {
 
   @Override
   public DnsClient createDnsClient() {
-    DnsResolverProvider provider = new DnsResolverProvider(this, addressResolverOptions);
-    InetSocketAddress address = provider.nameServerAddresses().get(0);
-    return new DnsClientImpl(this, address.getPort(), address.getAddress().getHostAddress(), DnsClientOptions.DEFAULT_QUERY_TIMEOUT);
+    return createDnsClient(new DnsClientOptions());
   }
 
   @Override
   public DnsClient createDnsClient(DnsClientOptions options) {
-    return new DnsClientImpl(this, options.getPort(), options.getHost(), options.getQueryTimeout());
+    String host = options.getHost();
+    int port = options.getPort();
+    if (host == null || port < 0) {
+      DnsResolverProvider provider = new DnsResolverProvider(this, addressResolverOptions);
+      InetSocketAddress address = provider.nameServerAddresses().get(0);
+      host = address.getAddress().getHostAddress();
+      port = address.getPort();
+    }
+    return new DnsClientImpl(this, port, host, options.getQueryTimeout());
   }
 
   private VertxMetrics initialiseMetrics(VertxOptions options) {

diff --git a/src/test/java/io/vertx/test/core/DNSTest.java b/src/test/java/io/vertx/test/core/DNSTest.java
@@ -29,6 +29,7 @@
 
 import java.net.InetSocketAddress;
 import java.util.List;
+import java.util.function.Function;
 
 import static io.vertx.test.core.TestUtils.assertIllegalStateException;
 import static io.vertx.test.core.TestUtils.assertNullPointerException;
@@ -62,14 +63,23 @@ public void testIllegalArguments() throws Exception {
 
   @Test
   public void testDefaultDnsClient() throws Exception {
+    testDefaultDnsClient(vertx -> vertx.createDnsClient());
+  }
+
+  @Test
+  public void testDefaultDnsClientWithOptions() throws Exception {
+    testDefaultDnsClient(vertx -> vertx.createDnsClient(new DnsClientOptions()));
+  }
+
+  private void testDefaultDnsClient(Function<Vertx, DnsClient> clientProvider) throws Exception {
     final String ip = "10.0.0.1";
     FakeDNSServer fakeDNSServer = FakeDNSServer.testLookup4(ip);
     fakeDNSServer.start();
     VertxOptions vertxOptions = new VertxOptions();
     InetSocketAddress fakeServerAddress = fakeDNSServer.localAddress();
     vertxOptions.getAddressResolverOptions().addServer(fakeServerAddress.getHostString() + ":" + fakeServerAddress.getPort());
     Vertx vertxWithFakeDns = Vertx.vertx(vertxOptions);
-    DnsClient dnsClient = vertxWithFakeDns.createDnsClient();
+    DnsClient dnsClient = clientProvider.apply(vertxWithFakeDns);
 
     dnsClient.lookup4("vertx.io", onSuccess(result -> {
       assertEquals(ip, result);
@@ -259,7 +269,7 @@ public void testLookup() throws Exception {
 
   @Test
   public void testTimeout() throws Exception {
-    DnsClient dns = vertx.createDnsClient(new DnsClientOptions().setPort(10000).setQueryTimeout(5000));
+    DnsClient dns = vertx.createDnsClient(new DnsClientOptions().setHost("localhost").setPort(10000).setQueryTimeout(5000));
 
     dns.lookup("vertx.io", onFailure(result -> {
       assertEquals(VertxException.class, result.getClass());