/**
* 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.hbase.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 java.util.Collection;
import javax.net.SocketFactory;
import org.apache.commons.logging.*;
import org.apache.hadoop.hbase.io.HbaseObjectWritable;
import org.apache.hadoop.io.*;
import org.apache.hadoop.ipc.Client;
import org.apache.hadoop.ipc.VersionedProtocol;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.conf.*;
/** A simple RPC mechanism.
*
* This is a local hbase copy of the hadoop RPC so we can do things like
* address HADOOP-414 for hbase-only and try other hbase-specific
* optimizations like using our own version of ObjectWritable. Class has been
* renamed to avoid confusing it w/ hadoop versions.
*
* <p>Below are continued the class comments from hadoop RPC class.
*
* 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.
*
* @see org.apache.hadoop.ipc.RPC
*/
public class HbaseRPC {
private static final Log LOG =
LogFactory.getLog("org.apache.hadoop.ipc.RPC");
private HbaseRPC() {} // 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 = Text.readString(in);
parameters = new Object[in.readInt()];
parameterClasses = new Class[parameters.length];
HbaseObjectWritable objectWritable = new HbaseObjectWritable();
for (int i = 0; i < parameters.length; i++) {
parameters[i] = HbaseObjectWritable.readObject(in, objectWritable, this.conf);
parameterClasses[i] = objectWritable.getDeclaredClass();
}
}
public void write(DataOutput out) throws IOException {
Text.writeString(out, methodName);
out.writeInt(parameterClasses.length);
for (int i = 0; i < parameterClasses.length; i++) {
HbaseObjectWritable.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;
}
}
private static Map<SocketFactory, Client> CLIENTS =
new HashMap<SocketFactory, Client>();
private static 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(HbaseObjectWritable.class, conf, factory);
CLIENTS.put(factory, client);
}
return client;
}
/**
* Construct & cache client with the default SocketFactory.
* @param conf
* @return
*/
private static Client getClient(Configuration conf) {
return getClient(conf, SocketFactory.getDefault());
}
/**
* Stop all RPC client connections
*/
public static synchronized void stopClient(){
for (Client client : CLIENTS.values())
client.stop();
CLIENTS.clear();
}
/*
* remove specified client from the list of clients.
*/
static synchronized void removeClients() {
CLIENTS.clear();
}
static synchronized Collection allClients() {
return CLIENTS.values();
}
private static class Invoker implements InvocationHandler {
private InetSocketAddress address;
private UserGroupInformation ticket;
private Client client;
public Invoker(InetSocketAddress address, UserGroupInformation ticket,
Configuration conf, SocketFactory factory) {
this.address = address;
this.ticket = ticket;
this.client = getClient(conf, factory);
}
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
long startTime = System.currentTimeMillis();
HbaseObjectWritable value = (HbaseObjectWritable)
client.call(new Invocation(method, args), address, ticket);
long callTime = System.currentTimeMillis() - startTime;
LOG.debug("Call: " + method.getName() + " " + callTime);
return value.get();
}
}
/**
* 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 prefered version
*/
public long getClientVersion() {
return clientVersion;
}
/**
* Get the server's agreed to version.
*/
public long getServerVersion() {
return serverVersion;
}
}
public static VersionedProtocol waitForProxy(Class protocol,
long clientVersion,
InetSocketAddress addr,
Configuration conf
) throws IOException {
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...");
} catch(SocketTimeoutException te) { // namenode is busy
LOG.info("Problem connecting to server: " + addr);
}
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<?> protocol,
long clientVersion, InetSocketAddress addr, Configuration conf,
SocketFactory factory) throws IOException {
return getProxy(protocol, clientVersion, addr, null, 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<?> protocol,
long clientVersion, InetSocketAddress addr, UserGroupInformation ticket,
Configuration conf, SocketFactory factory) throws IOException {
VersionedProtocol proxy =
(VersionedProtocol) Proxy.newProxyInstance(
protocol.getClassLoader(), new Class[] { protocol },
new Invoker(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<?> protocol,
long clientVersion, InetSocketAddress addr, Configuration conf)
throws IOException {
return getProxy(protocol, clientVersion, addr, conf, NetUtils
.getDefaultSocketFactory(conf));
}
/** Expert: Make multiple, parallel calls to a set of servers. */
public static Object[] call(Method method, Object[][] params,
InetSocketAddress[] addrs, Configuration conf)
throws IOException {
Invocation[] invocations = new Invocation[params.length];
for (int i = 0; i < params.length; i++)
invocations[i] = new Invocation(method, params[i]);
Writable[] wrappedValues = getClient(conf).call(invocations, addrs);
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] = ((HbaseObjectWritable)wrappedValues[i]).get();
return values;
}
/** 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 new Server(instance, conf, bindAddress, port, numHandlers, verbose);
}
/** An RPC Server. */
public static class Server extends org.apache.hadoop.ipc.Server {
private Object instance;
private Class<?> implementation;
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);
}
/** 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) throws IOException {
super(bindAddress, port, Invocation.class, numHandlers, conf);
this.instance = instance;
this.implementation = instance.getClass();
this.verbose = verbose;
}
public Writable call(Writable param, long receiveTime) throws IOException {
try {
Invocation call = (Invocation)param;
if (verbose) log("Call: " + call);
Method method =
implementation.getMethod(call.getMethodName(),
call.getParameterClasses());
long startTime = System.currentTimeMillis();
Object value = method.invoke(instance, call.getParameters());
long callTime = System.currentTimeMillis() - startTime;
LOG.debug("Served: " + call.getMethodName() + " " + callTime);
if (verbose) log("Return: "+value);
return new HbaseObjectWritable(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) {
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);
}
}