修复注册中心域名解析导致的单点问题 (#4293)

Fix #2545

Author: 356082462

dubbo-registry/dubbo-registry-api/src/main/java/com/alibaba/dubbo/registry/support/AbstractRegistryFactory.java

@@ -85,7 +85,7 @@ public Registry getRegistry(URL url) {
         url = url.setPath(RegistryService.class.getName())
                 .addParameter(Constants.INTERFACE_KEY, RegistryService.class.getName())
                 .removeParameters(Constants.EXPORT_KEY, Constants.REFER_KEY);
-        String key = url.toServiceString();
+        String key = url.toServiceStringWithoutResolving();
         // Lock the registry access process to ensure a single instance of the registry
         LOCK.lock();
         try {

dubbo-registry/dubbo-registry-api/src/test/java/com/alibaba/dubbo/registry/support/AbstractRegistryFactoryTest.java

@@ -21,7 +21,6 @@
 import com.alibaba.dubbo.registry.NotifyListener;
 import com.alibaba.dubbo.registry.Registry;
 import com.alibaba.dubbo.registry.RegistryFactory;
-
 import junit.framework.Assert;
 import org.junit.Test;
 
@@ -87,9 +86,15 @@ public void testRegistryFactoryCache() throws Exception {
 
     @Test
     public void testRegistryFactoryIpCache() throws Exception {
-        Registry registry1 = registryFactory.getRegistry(URL.valueOf("dubbo://" + NetUtils.getLocalAddress().getHostName() + ":2233"));
-        Registry registry2 = registryFactory.getRegistry(URL.valueOf("dubbo://" + NetUtils.getLocalAddress().getHostAddress() + ":2233"));
-        Assert.assertEquals(registry1, registry2);
+        String hostName = NetUtils.getLocalAddress().getHostName();
+        String ip = NetUtils.getLocalAddress().getHostAddress();
+        Registry registry1 = registryFactory.getRegistry(URL.valueOf("dubbo://" + hostName + ":2233"));
+        Registry registry2 = registryFactory.getRegistry(URL.valueOf("dubbo://" + ip + ":2233"));
+        if (hostName.equals(ip)) {
+            Assert.assertEquals(registry1, registry2);
+        } else {
+            Assert.assertNotSame(registry1, registry2);
+        }
     }
 
     @Test