/**
* Copyright 2010 The Apache Software Foundation
*
* 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 com.google.common.base.Function;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.client.RetriesExhaustedException;
import org.apache.hadoop.hbase.io.HbaseObjectWritable;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.ipc.VersionedProtocol;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.UserGroupInformation;
import javax.net.SocketFactory;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.net.ConnectException;
import java.net.InetSocketAddress;
import java.net.SocketTimeoutException;
import java.util.HashMap;
import java.util.Map;
/** 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>
*
*
* 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 HBaseRPC {
// Leave this out in the hadoop ipc package but keep class name. Do this
// so that we dont' get the logging of this class's invocations by doing our
// blanket enabling DEBUG on the o.a.h.h. package.
protected static final Log LOG =
LogFactory.getLog("org.apache.hadoop.ipc.HbaseRPC");
private HBaseRPC() {
super();
} // no public ctor
/** A method invocation, including the method name and its parameters.*/
public static class Invocation implements Writable, Configurable {
private String methodName;
@SuppressWarnings("unchecked")
private Class[] parameterClasses;
private Object[] parameters;
private Configuration conf;
/** default constructor */
public Invocation() {
super();
}
/**
* @param method method to call
* @param parameters parameters of call
*/
public Invocation(Method method, Object[] parameters) {
this.methodName = method.getName();
this.parameterClasses = method.getParameterTypes();
this.parameters = parameters;
}
/** @return The name of the method invoked. */
public String getMethodName() { return methodName; }
/** @return The parameter classes. */
@SuppressWarnings("unchecked")
public Class[] getParameterClasses() { return parameterClasses; }
/** @return The parameter instances. */
public Object[] getParameters() { return parameters; }
public void readFields(DataInput in) throws IOException {
methodName = in.readUTF();
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 {
out.writeUTF(this.methodName);
out.writeInt(parameterClasses.length);
for (int i = 0; i < parameterClasses.length; i++) {
HbaseObjectWritable.writeObject(out, parameters[i], parameterClasses[i],
conf);
}
}
@Override
public String toString() {
StringBuilder buffer = new StringBuilder(256);
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, HBaseClient> clients =
new HashMap<SocketFactory, HBaseClient>();
protected ClientCache() {}
/**
* Construct & cache an IPC client with the user-provided SocketFactory
* if no cached client exists.
*
* @param conf Configuration
* @param factory socket factory
* @return an IPC client
*/
protected synchronized HBaseClient 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).
HBaseClient client = clients.get(factory);
if (client == null) {
// Make an hbase client instead of hadoop Client.
client = new HBaseClient(HbaseObjectWritable.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
*/
protected synchronized HBaseClient 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.
* @param client client to stop
*/
protected void stopClient(HBaseClient client) {
synchronized (this) {
client.decCount();
if (client.isZeroReference()) {
clients.remove(client.getSocketFactory());
}
}
if (client.isZeroReference()) {
client.stop();
}
}
}
protected final static ClientCache CLIENTS = new ClientCache();
private static class Invoker implements InvocationHandler {
private InetSocketAddress address;
private UserGroupInformation ticket;
private HBaseClient client;
private boolean isClosed = false;
final private int rpcTimeout;
/**
* @param address address for invoker
* @param ticket ticket
* @param conf configuration
* @param factory socket factory
*/
public Invoker(InetSocketAddress address, UserGroupInformation ticket,
Configuration conf, SocketFactory factory, int rpcTimeout) {
this.address = address;
this.ticket = ticket;
this.client = CLIENTS.getClient(conf, factory);
this.rpcTimeout = rpcTimeout;
}
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable {
final boolean logDebug = LOG.isDebugEnabled();
long startTime = 0;
if (logDebug) {
startTime = System.currentTimeMillis();
}
HbaseObjectWritable value = (HbaseObjectWritable)
client.call(new Invocation(method, args), address, ticket, rpcTimeout);
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 protected void close() {
if (!isClosed) {
isClosed = true;
CLIENTS.stopClient(client);
}
}
}
/**
* A version mismatch for the RPC protocol.
*/
@SuppressWarnings("serial")
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;
}
/**
* @return the client's preferred version
*/
public long getClientVersion() {
return clientVersion;
}
/**
* @return the server's agreed to version.
*/
public long getServerVersion() {
return serverVersion;
}
}
/**
* @param protocol protocol interface
* @param clientVersion which client version we expect
* @param addr address of remote service
* @param conf configuration
* @param maxAttempts max attempts
* @param rpcTimeout timeout for each RPC
* @param timeout timeout in milliseconds
* @return proxy
* @throws IOException e
*/
@SuppressWarnings("unchecked")
public static VersionedProtocol waitForProxy(Class protocol,
long clientVersion,
InetSocketAddress addr,
Configuration conf,
int maxAttempts,
int rpcTimeout,
long timeout
) throws IOException {
// HBase does limited number of reconnects which is different from hadoop.
long startTime = System.currentTimeMillis();
IOException ioe;
int reconnectAttempts = 0;
while (true) {
try {
return getProxy(protocol, clientVersion, addr, conf, rpcTimeout);
} catch(ConnectException se) { // namenode has not been started
ioe = se;
if (maxAttempts >= 0 && ++reconnectAttempts >= maxAttempts) {
LOG.info("Server at " + addr + " could not be reached after " +
reconnectAttempts + " tries, giving up.");
throw new RetriesExhaustedException("Failed setting up proxy " +
protocol + " to " + addr.toString() + " after attempts=" +
reconnectAttempts, 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.
*
* @param protocol interface
* @param clientVersion version we are expecting
* @param addr remote address
* @param conf configuration
* @param factory socket factory
* @param rpcTimeout timeout for each RPC
* @return proxy
* @throws IOException e
*/
public static VersionedProtocol getProxy(Class<?> protocol,
long clientVersion, InetSocketAddress addr, Configuration conf,
SocketFactory factory, int rpcTimeout) throws IOException {
return getProxy(protocol, clientVersion, addr, null, conf, factory,
rpcTimeout);
}
/**
* Construct a client-side proxy object that implements the named protocol,
* talking to a server at the named address.
*
* @param protocol interface
* @param clientVersion version we are expecting
* @param addr remote address
* @param ticket ticket
* @param conf configuration
* @param factory socket factory
* @param rpcTimeout timeout for each RPC
* @return proxy
* @throws IOException e
*/
public static VersionedProtocol getProxy(Class<?> protocol,
long clientVersion, InetSocketAddress addr, UserGroupInformation ticket,
Configuration conf, SocketFactory factory, int rpcTimeout)
throws IOException {
VersionedProtocol proxy =
(VersionedProtocol) Proxy.newProxyInstance(
protocol.getClassLoader(), new Class[] { protocol },
new Invoker(addr, ticket, conf, factory, rpcTimeout));
long serverVersion = proxy.getProtocolVersion(protocol.getName(),
clientVersion);
if (serverVersion == clientVersion) {
return proxy;
}
throw new VersionMismatch(protocol.getName(), clientVersion,
serverVersion);
}
/**
* Construct a client-side proxy object with the default SocketFactory
*
* @param protocol interface
* @param clientVersion version we are expecting
* @param addr remote address
* @param conf configuration
* @param rpcTimeout timeout for each RPC
* @return a proxy instance
* @throws IOException e
*/
public static VersionedProtocol getProxy(Class<?> protocol,
long clientVersion, InetSocketAddress addr, Configuration conf,
int rpcTimeout)
throws IOException {
return getProxy(protocol, clientVersion, addr, conf, NetUtils
.getDefaultSocketFactory(conf), rpcTimeout);
}
/**
* 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.
*
* @param method method to invoke
* @param params array of parameters
* @param addrs array of addresses
* @param conf configuration
* @return values
* @throws IOException e
*/
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]);
HBaseClient client = CLIENTS.getClient(conf);
try {
Writable[] wrappedValues = client.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;
} finally {
CLIENTS.stopClient(client);
}
}
/**
* Construct a server for a protocol implementation instance listening on a
* port and address.
*
* @param instance instance
* @param bindAddress bind address
* @param port port to bind to
* @param numHandlers number of handlers to start
* @param verbose verbose flag
* @param conf configuration
* @return Server
* @throws IOException e
*/
public static Server getServer(final Object instance,
final Class<?>[] ifaces,
final String bindAddress, final int port,
final int numHandlers,
int metaHandlerCount, final boolean verbose, Configuration conf, int highPriorityLevel)
throws IOException {
return new Server(instance, ifaces, conf, bindAddress, port, numHandlers, metaHandlerCount, verbose, highPriorityLevel);
}
/** An RPC Server. */
public static class Server extends HBaseServer {
private Object instance;
private Class<?> implementation;
private Class<?> ifaces[];
private boolean verbose;
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
* @throws IOException e
*/
public Server(Object instance, final Class<?>[] ifaces,
Configuration conf, String bindAddress, int port,
int numHandlers, int metaHandlerCount, boolean verbose, int highPriorityLevel) throws IOException {
super(bindAddress, port, Invocation.class, numHandlers, metaHandlerCount, conf, classNameBase(instance.getClass().getName()), highPriorityLevel);
this.instance = instance;
this.implementation = instance.getClass();
this.verbose = verbose;
this.ifaces = ifaces;
// create metrics for the advertised interfaces this server implements.
this.rpcMetrics.createMetrics(this.ifaces);
}
@Override
public Writable call(Writable param, long receivedTime) throws IOException {
try {
Invocation call = (Invocation)param;
if(call.getMethodName() == null) {
throw new IOException("Could not find requested method, the usual " +
"cause is a version mismatch between client and server.");
}
if (verbose) log("Call: " + call);
Method method =
implementation.getMethod(call.getMethodName(),
call.getParameterClasses());
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.rpcQueueTime.inc(qTime);
rpcMetrics.rpcProcessingTime.inc(processingTime);
rpcMetrics.inc(call.getMethodName(), processingTime);
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;
}
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;
}
}
}
protected static void log(String value) {
String v = value;
if (v != null && v.length() > 55)
v = v.substring(0, 55)+"...";
LOG.info(v);
}
}