HADOOP-15340. Provide meaningful RPC server name for RpcMetrics. Contributed by Elek Marton.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/ProtobufRpcEngine.java

@@ -419,8 +419,9 @@ public class ProtobufRpcEngine implements RpcEngine {
         String portRangeConfig)
         throws IOException {
       super(bindAddress, port, null, numHandlers,
-          numReaders, queueSizePerHandler, conf, classNameBase(protocolImpl
-              .getClass().getName()), secretManager, portRangeConfig);
+          numReaders, queueSizePerHandler, conf,
+          serverNameFromClass(protocolImpl.getClass()), secretManager,
+          portRangeConfig);
       this.verbose = verbose;  
       registerProtocolAndImpl(RPC.RpcKind.RPC_PROTOCOL_BUFFER, protocolClass,
           protocolImpl);

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/RPC.java

@@ -35,6 +35,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.HashMap;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import javax.net.SocketFactory;
 
@@ -808,13 +810,45 @@ public class RPC {
   
   /** An RPC Server. */
   public abstract static class Server extends org.apache.hadoop.ipc.Server {
-   boolean verbose;
-   static String classNameBase(String className) {
-      String[] names = className.split("\\.", -1);
-      if (names == null || names.length == 0) {
-        return className;
+
+    boolean verbose;
+
+    private static final Pattern COMPLEX_SERVER_NAME_PATTERN =
+        Pattern.compile("(?:[^\\$]*\\$)*([A-Za-z][^\\$]+)(?:\\$\\d+)?");
+
+    /**
+     * Get a meaningful and short name for a server based on a java class.
+     *
+     * The rules are defined to support the current naming schema of the
+     * generated protobuf classes where the final class usually an anonymous
+     * inner class of an inner class.
+     *
+     * 1. For simple classes it returns with the simple name of the classes
+     *     (with the name without package name)
+     *
+     * 2. For inner classes, this is the simple name of the inner class.
+     *
+     * 3.  If it is an Object created from a class factory
+     *   E.g., org.apache.hadoop.ipc.TestRPC$TestClass$2
+     * this method returns parent class TestClass.
+     *
+     * 4. If it is an anonymous class E.g., 'org.apache.hadoop.ipc.TestRPC$10'
+     * serverNameFromClass returns parent class TestRPC.
+     *
+     *
+     */
+    static String serverNameFromClass(Class<?> clazz) {
+      String name = clazz.getName();
+      String[] names = clazz.getName().split("\\.", -1);
+      if (names != null && names.length > 0) {
+        name = names[names.length - 1];
+      }
+      Matcher matcher = COMPLEX_SERVER_NAME_PATTERN.matcher(name);
+      if (matcher.find()) {
+        return matcher.group(1);
+      } else {
+        return name;
       }
-      return names[names.length-1];
     }
    
    /**

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Server.java

@@ -140,6 +140,10 @@ public abstract class Server {
   private RpcSaslProto negotiateResponse;
   private ExceptionsHandler exceptionsHandler = new ExceptionsHandler();
   private Tracer tracer;
+  /**
+   * Logical name of the server used in metrics and monitor.
+   */
+  private final String serverName;
   
   /**
    * Add exception classes for which server won't log stack traces.
@@ -2768,6 +2772,7 @@ public abstract class Server {
     this.rpcRequestClass = rpcRequestClass; 
     this.handlerCount = handlerCount;
     this.socketSendBufferSize = 0;
+    this.serverName = serverName;
     this.maxDataLength = conf.getInt(CommonConfigurationKeys.IPC_MAXIMUM_DATA_LENGTH,
         CommonConfigurationKeys.IPC_MAXIMUM_DATA_LENGTH_DEFAULT);
     if (queueSizePerHandler != -1) {
@@ -3509,4 +3514,8 @@ public abstract class Server {
       idleScanTimer.schedule(idleScanTask, idleScanInterval);
     }
   }
+
+  public String getServerName() {
+    return serverName;
+  }
 }

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/WritableRpcEngine.java

@@ -406,7 +406,7 @@ public class WritableRpcEngine implements RpcEngine {
         throws IOException {
       super(bindAddress, port, null, numHandlers, numReaders,
           queueSizePerHandler, conf,
-          classNameBase(protocolImpl.getClass().getName()), secretManager,
+          serverNameFromClass(protocolImpl.getClass()), secretManager,
           portRangeConfig);
 
       this.verbose = verbose;

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/metrics/RpcMetrics.java

@@ -17,10 +17,12 @@
  */
 package org.apache.hadoop.ipc.metrics;
 
+import com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
 import org.apache.hadoop.ipc.Server;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.metrics2.MetricsTag;
 import org.apache.hadoop.metrics2.annotation.Metric;
 import org.apache.hadoop.metrics2.annotation.Metrics;
 import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
@@ -50,7 +52,9 @@ public class RpcMetrics {
     String port = String.valueOf(server.getListenerAddress().getPort());
     name = "RpcActivityForPort" + port;
     this.server = server;
-    registry = new MetricsRegistry("rpc").tag("port", "RPC port", port);
+    registry = new MetricsRegistry("rpc")
+        .tag("port", "RPC port", port)
+        .tag("serverName", "Name of the RPC server", server.getServerName());
     int[] intervals = conf.getInts(
         CommonConfigurationKeys.RPC_METRICS_PERCENTILES_INTERVALS_KEY);
     rpcQuantileEnable = (intervals.length > 0) && conf.getBoolean(
@@ -292,4 +296,9 @@ public class RpcMetrics {
   public double getDeferredRpcProcessingStdDev() {
     return deferredRpcProcessingTime.lastStat().stddev();
   }
+
+  @VisibleForTesting
+  public MetricsTag getTag(String tagName) {
+    return registry.getTag(tagName);
+  }
 }

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ipc/TestRPC.java

@@ -48,6 +48,7 @@ import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.test.MetricsAsserts;
 import org.apache.hadoop.test.MockitoUtil;
+import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mockito;
@@ -90,8 +91,6 @@ import static org.apache.hadoop.test.MetricsAsserts.assertCounterGt;
 import static org.apache.hadoop.test.MetricsAsserts.getLongCounter;
 import static org.apache.hadoop.test.MetricsAsserts.getMetrics;
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNotSame;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
@@ -447,6 +446,15 @@ public class TestRPC extends TestRpcBase {
       assertCounterGt("SentBytes", 0L, rb);
       assertCounterGt("ReceivedBytes", 0L, rb);
 
+      // Check tags of the metrics
+      assertEquals("" + server.getPort(),
+          server.getRpcMetrics().getTag("port").value());
+
+      assertEquals("TestProtobufRpcProto",
+          server.getRpcMetrics().getTag("serverName").value());
+
+
+
       // Number of calls to echo method should be 2
       rb = getMetrics(server.rpcDetailedMetrics.name());
       assertCounter("EchoNumOps", 2L, rb);
@@ -1362,6 +1370,50 @@ public class TestRPC extends TestRpcBase {
     }
   }
 
+  @Test
+  public void testServerNameFromClass() {
+    Assert.assertEquals("TestRPC",
+        RPC.Server.serverNameFromClass(this.getClass()));
+    Assert.assertEquals("TestClass",
+        RPC.Server.serverNameFromClass(TestRPC.TestClass.class));
+
+    Object testing = new TestClass().classFactory();
+    Assert.assertEquals("Embedded",
+        RPC.Server.serverNameFromClass(testing.getClass()));
+
+    testing = new TestClass().classFactoryAbstract();
+    Assert.assertEquals("TestClass",
+        RPC.Server.serverNameFromClass(testing.getClass()));
+
+    testing = new TestClass().classFactoryObject();
+    Assert.assertEquals("TestClass",
+        RPC.Server.serverNameFromClass(testing.getClass()));
+
+  }
+
+  static class TestClass {
+    class Embedded {
+    }
+
+    abstract class AbstractEmbedded {
+
+    }
+
+    private Object classFactory() {
+      return new Embedded();
+    }
+
+    private Object classFactoryAbstract() {
+      return new AbstractEmbedded() {
+      };
+    }
+
+    private Object classFactoryObject() {
+      return new Object() {
+      };
+    }
+
+  }
   public static class FakeRequestClass extends RpcWritable {
     static volatile IOException exception;
     @Override