| /** |
| * 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.hadoop.ipc; |
| |
| import java.lang.reflect.Proxy; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Array; |
| import java.lang.reflect.InvocationHandler; |
| import java.lang.reflect.InvocationTargetException; |
| |
| import java.net.ConnectException; |
| import java.net.InetSocketAddress; |
| import java.net.SocketTimeoutException; |
| import java.io.*; |
| import java.util.Map; |
| import java.util.HashMap; |
| |
| import javax.net.SocketFactory; |
| |
| import org.apache.commons.logging.*; |
| |
| import org.apache.hadoop.io.*; |
| import org.apache.hadoop.security.SaslRpcServer; |
| import org.apache.hadoop.security.UserGroupInformation; |
| import org.apache.hadoop.security.token.SecretManager; |
| import org.apache.hadoop.security.token.TokenIdentifier; |
| import org.apache.hadoop.conf.*; |
| |
| import org.apache.hadoop.net.NetUtils; |
| |
| /** A simple RPC mechanism. |
| * |
| * A <i>protocol</i> is a Java interface. All parameters and return types must |
| * be one of: |
| * |
| * <ul> <li>a primitive type, <code>boolean</code>, <code>byte</code>, |
| * <code>char</code>, <code>short</code>, <code>int</code>, <code>long</code>, |
| * <code>float</code>, <code>double</code>, or <code>void</code>; or</li> |
| * |
| * <li>a {@link String}; or</li> |
| * |
| * <li>a {@link Writable}; or</li> |
| * |
| * <li>an array of the above types</li> </ul> |
| * |
| * All methods in the protocol should throw only IOException. No field data of |
| * the protocol instance is transmitted. |
| */ |
| public class RPC { |
| private static final Log LOG = |
| LogFactory.getLog(RPC.class); |
| |
| private RPC() {} // no public ctor |
| |
| |
| /** A method invocation, including the method name and its parameters.*/ |
| private static class Invocation implements Writable, Configurable { |
| private String methodName; |
| private Class[] parameterClasses; |
| private Object[] parameters; |
| private Configuration conf; |
| |
| public Invocation() {} |
| |
| public Invocation(Method method, Object[] parameters) { |
| this.methodName = method.getName(); |
| this.parameterClasses = method.getParameterTypes(); |
| this.parameters = parameters; |
| } |
| |
| /** The name of the method invoked. */ |
| public String getMethodName() { return methodName; } |
| |
| /** The parameter classes. */ |
| public Class[] getParameterClasses() { return parameterClasses; } |
| |
| /** The parameter instances. */ |
| public Object[] getParameters() { return parameters; } |
| |
| public void readFields(DataInput in) throws IOException { |
| methodName = UTF8.readString(in); |
| parameters = new Object[in.readInt()]; |
| parameterClasses = new Class[parameters.length]; |
| ObjectWritable objectWritable = new ObjectWritable(); |
| for (int i = 0; i < parameters.length; i++) { |
| parameters[i] = ObjectWritable.readObject(in, objectWritable, this.conf); |
| parameterClasses[i] = objectWritable.getDeclaredClass(); |
| } |
| } |
| |
| public void write(DataOutput out) throws IOException { |
| UTF8.writeString(out, methodName); |
| out.writeInt(parameterClasses.length); |
| for (int i = 0; i < parameterClasses.length; i++) { |
| ObjectWritable.writeObject(out, parameters[i], parameterClasses[i], |
| conf); |
| } |
| } |
| |
| public String toString() { |
| StringBuffer buffer = new StringBuffer(); |
| buffer.append(methodName); |
| buffer.append("("); |
| for (int i = 0; i < parameters.length; i++) { |
| if (i != 0) |
| buffer.append(", "); |
| buffer.append(parameters[i]); |
| } |
| buffer.append(")"); |
| return buffer.toString(); |
| } |
| |
| public void setConf(Configuration conf) { |
| this.conf = conf; |
| } |
| |
| public Configuration getConf() { |
| return this.conf; |
| } |
| |
| } |
| |
| /* Cache a client using its socket factory as the hash key */ |
| static private class ClientCache { |
| private Map<SocketFactory, Client> clients = |
| new HashMap<SocketFactory, Client>(); |
| |
| /** |
| * Construct & cache an IPC client with the user-provided SocketFactory |
| * if no cached client exists. |
| * |
| * @param conf Configuration |
| * @return an IPC client |
| */ |
| private synchronized Client getClient(Configuration conf, |
| SocketFactory factory) { |
| // Construct & cache client. The configuration is only used for timeout, |
| // and Clients have connection pools. So we can either (a) lose some |
| // connection pooling and leak sockets, or (b) use the same timeout for all |
| // configurations. Since the IPC is usually intended globally, not |
| // per-job, we choose (a). |
| Client client = clients.get(factory); |
| if (client == null) { |
| client = new Client(ObjectWritable.class, conf, factory); |
| clients.put(factory, client); |
| } else { |
| client.incCount(); |
| } |
| return client; |
| } |
| |
| /** |
| * Construct & cache an IPC client with the default SocketFactory |
| * if no cached client exists. |
| * |
| * @param conf Configuration |
| * @return an IPC client |
| */ |
| private synchronized Client getClient(Configuration conf) { |
| return getClient(conf, SocketFactory.getDefault()); |
| } |
| |
| /** |
| * Stop a RPC client connection |
| * A RPC client is closed only when its reference count becomes zero. |
| */ |
| private void stopClient(Client client) { |
| synchronized (this) { |
| client.decCount(); |
| if (client.isZeroReference()) { |
| clients.remove(client.getSocketFactory()); |
| } |
| } |
| if (client.isZeroReference()) { |
| client.stop(); |
| } |
| } |
| } |
| |
| private static ClientCache CLIENTS=new ClientCache(); |
| |
| //for unit testing only |
| static Client getClient(Configuration conf) { |
| return CLIENTS.getClient(conf); |
| } |
| |
| private static class Invoker implements InvocationHandler { |
| private Client.ConnectionId remoteId; |
| private Client client; |
| private boolean isClosed = false; |
| |
| public Invoker(Class<? extends VersionedProtocol> protocol, |
| InetSocketAddress address, UserGroupInformation ticket, |
| Configuration conf, SocketFactory factory) throws IOException { |
| this.remoteId = Client.ConnectionId.getConnectionId(address, protocol, |
| ticket, conf); |
| this.client = CLIENTS.getClient(conf, factory); |
| } |
| |
| public Object invoke(Object proxy, Method method, Object[] args) |
| throws Throwable { |
| final boolean logDebug = LOG.isDebugEnabled(); |
| long startTime = 0; |
| if (logDebug) { |
| startTime = System.currentTimeMillis(); |
| } |
| |
| ObjectWritable value = (ObjectWritable) |
| client.call(new Invocation(method, args), remoteId); |
| if (logDebug) { |
| long callTime = System.currentTimeMillis() - startTime; |
| LOG.debug("Call: " + method.getName() + " " + callTime); |
| } |
| return value.get(); |
| } |
| |
| /* close the IPC client that's responsible for this invoker's RPCs */ |
| synchronized private void close() { |
| if (!isClosed) { |
| isClosed = true; |
| CLIENTS.stopClient(client); |
| } |
| } |
| } |
| |
| /** |
| * A version mismatch for the RPC protocol. |
| */ |
| public static class VersionMismatch extends IOException { |
| private String interfaceName; |
| private long clientVersion; |
| private long serverVersion; |
| |
| /** |
| * Create a version mismatch exception |
| * @param interfaceName the name of the protocol mismatch |
| * @param clientVersion the client's version of the protocol |
| * @param serverVersion the server's version of the protocol |
| */ |
| public VersionMismatch(String interfaceName, long clientVersion, |
| long serverVersion) { |
| super("Protocol " + interfaceName + " version mismatch. (client = " + |
| clientVersion + ", server = " + serverVersion + ")"); |
| this.interfaceName = interfaceName; |
| this.clientVersion = clientVersion; |
| this.serverVersion = serverVersion; |
| } |
| |
| /** |
| * Get the interface name |
| * @return the java class name |
| * (eg. org.apache.hadoop.mapred.InterTrackerProtocol) |
| */ |
| public String getInterfaceName() { |
| return interfaceName; |
| } |
| |
| /** |
| * Get the client's preferred version |
| */ |
| public long getClientVersion() { |
| return clientVersion; |
| } |
| |
| /** |
| * Get the server's agreed to version. |
| */ |
| public long getServerVersion() { |
| return serverVersion; |
| } |
| } |
| |
| public static VersionedProtocol waitForProxy( |
| Class<? extends VersionedProtocol> protocol, |
| long clientVersion, |
| InetSocketAddress addr, |
| Configuration conf |
| ) throws IOException { |
| return waitForProxy(protocol, clientVersion, addr, conf, Long.MAX_VALUE); |
| } |
| |
| /** |
| * Get a proxy connection to a remote server |
| * @param protocol protocol class |
| * @param clientVersion client version |
| * @param addr remote address |
| * @param conf configuration to use |
| * @param timeout time in milliseconds before giving up |
| * @return the proxy |
| * @throws IOException if the far end through a RemoteException |
| */ |
| static VersionedProtocol waitForProxy( |
| Class<? extends VersionedProtocol> protocol, |
| long clientVersion, |
| InetSocketAddress addr, |
| Configuration conf, |
| long timeout |
| ) throws IOException { |
| long startTime = System.currentTimeMillis(); |
| IOException ioe; |
| while (true) { |
| try { |
| return getProxy(protocol, clientVersion, addr, conf); |
| } catch(ConnectException se) { // namenode has not been started |
| LOG.info("Server at " + addr + " not available yet, Zzzzz..."); |
| ioe = se; |
| } catch(SocketTimeoutException te) { // namenode is busy |
| LOG.info("Problem connecting to server: " + addr); |
| ioe = te; |
| } |
| // check if timed out |
| if (System.currentTimeMillis()-timeout >= startTime) { |
| throw ioe; |
| } |
| |
| // wait for retry |
| try { |
| Thread.sleep(1000); |
| } catch (InterruptedException ie) { |
| // IGNORE |
| } |
| } |
| } |
| /** Construct a client-side proxy object that implements the named protocol, |
| * talking to a server at the named address. */ |
| public static VersionedProtocol getProxy( |
| Class<? extends VersionedProtocol> protocol, |
| long clientVersion, InetSocketAddress addr, Configuration conf, |
| SocketFactory factory) throws IOException { |
| UserGroupInformation ugi = UserGroupInformation.getCurrentUser(); |
| return getProxy(protocol, clientVersion, addr, ugi, conf, factory); |
| } |
| |
| /** Construct a client-side proxy object that implements the named protocol, |
| * talking to a server at the named address. */ |
| public static VersionedProtocol getProxy( |
| Class<? extends VersionedProtocol> protocol, |
| long clientVersion, InetSocketAddress addr, UserGroupInformation ticket, |
| Configuration conf, SocketFactory factory) throws IOException { |
| |
| if (UserGroupInformation.isSecurityEnabled()) { |
| SaslRpcServer.init(conf); |
| } |
| VersionedProtocol proxy = |
| (VersionedProtocol) Proxy.newProxyInstance( |
| protocol.getClassLoader(), new Class[] { protocol }, |
| new Invoker(protocol, addr, ticket, conf, factory)); |
| long serverVersion = proxy.getProtocolVersion(protocol.getName(), |
| clientVersion); |
| if (serverVersion == clientVersion) { |
| return proxy; |
| } else { |
| throw new VersionMismatch(protocol.getName(), clientVersion, |
| serverVersion); |
| } |
| } |
| |
| /** |
| * Construct a client-side proxy object with the default SocketFactory |
| * |
| * @param protocol |
| * @param clientVersion |
| * @param addr |
| * @param conf |
| * @return a proxy instance |
| * @throws IOException |
| */ |
| public static VersionedProtocol getProxy( |
| Class<? extends VersionedProtocol> protocol, |
| long clientVersion, InetSocketAddress addr, Configuration conf) |
| throws IOException { |
| |
| return getProxy(protocol, clientVersion, addr, conf, |
| NetUtils.getDefaultSocketFactory(conf)); |
| } |
| |
| /** |
| * Stop this proxy and release its invoker's resource |
| * @param proxy the proxy to be stopped |
| */ |
| public static void stopProxy(VersionedProtocol proxy) { |
| if (proxy!=null) { |
| ((Invoker)Proxy.getInvocationHandler(proxy)).close(); |
| } |
| } |
| |
| /** |
| * Expert: Make multiple, parallel calls to a set of servers. |
| * @deprecated Use {@link #call(Method, Object[][], InetSocketAddress[], UserGroupInformation, Configuration)} instead |
| */ |
| public static Object[] call(Method method, Object[][] params, |
| InetSocketAddress[] addrs, Configuration conf) |
| throws IOException, InterruptedException { |
| return call(method, params, addrs, null, conf); |
| } |
| |
| /** Expert: Make multiple, parallel calls to a set of servers. */ |
| public static Object[] call(Method method, Object[][] params, |
| InetSocketAddress[] addrs, |
| UserGroupInformation ticket, Configuration conf) |
| throws IOException, InterruptedException { |
| |
| Invocation[] invocations = new Invocation[params.length]; |
| for (int i = 0; i < params.length; i++) |
| invocations[i] = new Invocation(method, params[i]); |
| Client client = CLIENTS.getClient(conf); |
| try { |
| Writable[] wrappedValues = |
| client.call(invocations, addrs, method.getDeclaringClass(), ticket, conf); |
| |
| if (method.getReturnType() == Void.TYPE) { |
| return null; |
| } |
| |
| Object[] values = |
| (Object[])Array.newInstance(method.getReturnType(), wrappedValues.length); |
| for (int i = 0; i < values.length; i++) |
| if (wrappedValues[i] != null) |
| values[i] = ((ObjectWritable)wrappedValues[i]).get(); |
| |
| return values; |
| } finally { |
| CLIENTS.stopClient(client); |
| } |
| } |
| |
| /** Construct a server for a protocol implementation instance listening on a |
| * port and address. */ |
| public static Server getServer(final Object instance, final String bindAddress, final int port, Configuration conf) |
| throws IOException { |
| return getServer(instance, bindAddress, port, 1, false, conf); |
| } |
| |
| /** Construct a server for a protocol implementation instance listening on a |
| * port and address. */ |
| public static Server getServer(final Object instance, final String bindAddress, final int port, |
| final int numHandlers, |
| final boolean verbose, Configuration conf) |
| throws IOException { |
| return getServer(instance, bindAddress, port, numHandlers, verbose, conf, null); |
| } |
| |
| /** Construct a server for a protocol implementation instance listening on a |
| * port and address, with a secret manager. */ |
| public static Server getServer(final Object instance, final String bindAddress, final int port, |
| final int numHandlers, |
| final boolean verbose, Configuration conf, |
| SecretManager<? extends TokenIdentifier> secretManager) |
| throws IOException { |
| return new Server(instance, conf, bindAddress, port, numHandlers, verbose, secretManager); |
| } |
| |
| /** An RPC Server. */ |
| public static class Server extends org.apache.hadoop.ipc.Server { |
| private Object instance; |
| private boolean verbose; |
| |
| /** Construct an RPC server. |
| * @param instance the instance whose methods will be called |
| * @param conf the configuration to use |
| * @param bindAddress the address to bind on to listen for connection |
| * @param port the port to listen for connections on |
| */ |
| public Server(Object instance, Configuration conf, String bindAddress, int port) |
| throws IOException { |
| this(instance, conf, bindAddress, port, 1, false, null); |
| } |
| |
| private static String classNameBase(String className) { |
| String[] names = className.split("\\.", -1); |
| if (names == null || names.length == 0) { |
| return className; |
| } |
| return names[names.length-1]; |
| } |
| |
| /** Construct an RPC server. |
| * @param instance the instance whose methods will be called |
| * @param conf the configuration to use |
| * @param bindAddress the address to bind on to listen for connection |
| * @param port the port to listen for connections on |
| * @param numHandlers the number of method handler threads to run |
| * @param verbose whether each call should be logged |
| */ |
| public Server(Object instance, Configuration conf, String bindAddress, int port, |
| int numHandlers, boolean verbose, |
| SecretManager<? extends TokenIdentifier> secretManager) |
| throws IOException { |
| super(bindAddress, port, Invocation.class, numHandlers, conf, |
| classNameBase(instance.getClass().getName()), secretManager); |
| this.instance = instance; |
| this.verbose = verbose; |
| } |
| |
| public Writable call(Class<?> protocol, Writable param, long receivedTime) |
| throws IOException { |
| try { |
| Invocation call = (Invocation)param; |
| if (verbose) log("Call: " + call); |
| |
| Method method = |
| protocol.getMethod(call.getMethodName(), |
| call.getParameterClasses()); |
| method.setAccessible(true); |
| |
| long startTime = System.currentTimeMillis(); |
| Object value = method.invoke(instance, call.getParameters()); |
| int processingTime = (int) (System.currentTimeMillis() - startTime); |
| int qTime = (int) (startTime-receivedTime); |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Served: " + call.getMethodName() + |
| " queueTime= " + qTime + |
| " procesingTime= " + processingTime); |
| } |
| rpcMetrics.addRpcQueueTime(qTime); |
| rpcMetrics.addRpcProcessingTime(processingTime); |
| rpcMetrics.addRpcProcessingTime(call.getMethodName(), processingTime); |
| if (verbose) log("Return: "+value); |
| |
| return new ObjectWritable(method.getReturnType(), value); |
| |
| } catch (InvocationTargetException e) { |
| Throwable target = e.getTargetException(); |
| if (target instanceof IOException) { |
| throw (IOException)target; |
| } else { |
| IOException ioe = new IOException(target.toString()); |
| ioe.setStackTrace(target.getStackTrace()); |
| throw ioe; |
| } |
| } catch (Throwable e) { |
| if (!(e instanceof IOException)) { |
| LOG.error("Unexpected throwable object ", e); |
| } |
| IOException ioe = new IOException(e.toString()); |
| ioe.setStackTrace(e.getStackTrace()); |
| throw ioe; |
| } |
| } |
| } |
| |
| private static void log(String value) { |
| if (value!= null && value.length() > 55) |
| value = value.substring(0, 55)+"..."; |
| LOG.info(value); |
| } |
| } |