/*
* 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.coprocessor;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.Coprocessor;
import org.apache.hadoop.hbase.CoprocessorEnvironment;
import org.apache.hadoop.hbase.DoNotRetryIOException;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.client.coprocessor.Batch;
import org.apache.hadoop.hbase.ipc.CoprocessorProtocol;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.SortedCopyOnWriteSet;
import org.apache.hadoop.hbase.util.VersionInfo;
import org.apache.hadoop.hbase.Server;
import org.apache.hadoop.io.IOUtils;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.*;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
/**
* Provides the common setup framework and runtime services for coprocessor
* invocation from HBase services.
* @param <E> the specific environment extension that a concrete implementation
* provides
*/
public abstract class CoprocessorHost<E extends CoprocessorEnvironment> {
public static final String REGION_COPROCESSOR_CONF_KEY =
"hbase.coprocessor.region.classes";
public static final String USER_REGION_COPROCESSOR_CONF_KEY =
"hbase.coprocessor.user.region.classes";
public static final String MASTER_COPROCESSOR_CONF_KEY =
"hbase.coprocessor.master.classes";
public static final String WAL_COPROCESSOR_CONF_KEY =
"hbase.coprocessor.wal.classes";
private static final Log LOG = LogFactory.getLog(CoprocessorHost.class);
/** Ordered set of loaded coprocessors with lock */
protected SortedSet<E> coprocessors =
new SortedCopyOnWriteSet<E>(new EnvironmentPriorityComparator());
protected Configuration conf;
// unique file prefix to use for local copies of jars when classloading
protected String pathPrefix;
protected volatile int loadSequence;
public CoprocessorHost() {
pathPrefix = UUID.randomUUID().toString();
}
/**
* Not to be confused with the per-object _coprocessors_ (above),
* coprocessorNames is static and stores the set of all coprocessors ever
* loaded by any thread in this JVM. It is strictly additive: coprocessors are
* added to coprocessorNames, by loadInstance() but are never removed, since
* the intention is to preserve a history of all loaded coprocessors for
* diagnosis in case of server crash (HBASE-4014).
*/
private static Set<String> coprocessorNames =
Collections.synchronizedSet(new HashSet<String>());
public static Set<String> getLoadedCoprocessors() {
return coprocessorNames;
}
/**
* Used to create a parameter to the HServerLoad constructor so that
* HServerLoad can provide information about the coprocessors loaded by this
* regionserver.
* (HBASE-4070: Improve region server metrics to report loaded coprocessors
* to master).
*/
public Set<String> getCoprocessors() {
Set<String> returnValue = new TreeSet<String>();
for(CoprocessorEnvironment e: coprocessors) {
returnValue.add(e.getInstance().getClass().getSimpleName());
}
return returnValue;
}
/**
* Load system coprocessors. Read the class names from configuration.
* Called by constructor.
*/
protected void loadSystemCoprocessors(Configuration conf, String confKey) {
Class<?> implClass = null;
// load default coprocessors from configure file
String[] defaultCPClasses = conf.getStrings(confKey);
if (defaultCPClasses == null || defaultCPClasses.length == 0)
return;
int priority = Coprocessor.PRIORITY_SYSTEM;
List<E> configured = new ArrayList<E>();
for (String className : defaultCPClasses) {
className = className.trim();
if (findCoprocessor(className) != null) {
continue;
}
ClassLoader cl = this.getClass().getClassLoader();
Thread.currentThread().setContextClassLoader(cl);
try {
implClass = cl.loadClass(className);
configured.add(loadInstance(implClass, Coprocessor.PRIORITY_SYSTEM, conf));
LOG.info("System coprocessor " + className + " was loaded " +
"successfully with priority (" + priority++ + ").");
} catch (ClassNotFoundException e) {
LOG.warn("Class " + className + " cannot be found. " +
e.getMessage());
} catch (IOException e) {
LOG.warn("Load coprocessor " + className + " failed. " +
e.getMessage());
}
}
// add entire set to the collection for COW efficiency
coprocessors.addAll(configured);
}
/**
* Load a coprocessor implementation into the host
* @param path path to implementation jar
* @param className the main class name
* @param priority chaining priority
* @param conf configuration for coprocessor
* @throws java.io.IOException Exception
*/
@SuppressWarnings("deprecation")
public E load(Path path, String className, int priority,
Configuration conf) throws IOException {
Class<?> implClass = null;
// Have we already loaded the class, perhaps from an earlier region open
// for the same table?
try {
implClass = getClass().getClassLoader().loadClass(className);
} catch (ClassNotFoundException e) {
LOG.info("Class " + className + " needs to be loaded from a file - " +
path.toString() + ".");
// go ahead to load from file system.
}
// If not, load
if (implClass == null) {
// copy the jar to the local filesystem
if (!path.toString().endsWith(".jar")) {
throw new IOException(path.toString() + ": not a jar file?");
}
FileSystem fs = path.getFileSystem(HBaseConfiguration.create());
Path dst = new Path(System.getProperty("java.io.tmpdir") +
java.io.File.separator +"." + pathPrefix +
"." + className + "." + System.currentTimeMillis() + ".jar");
fs.copyToLocalFile(path, dst);
fs.deleteOnExit(dst);
// TODO: code weaving goes here
// TODO: wrap heap allocations and enforce maximum usage limits
/* TODO: inject code into loop headers that monitors CPU use and
aborts runaway user code */
// load the jar and get the implementation main class
String cp = System.getProperty("java.class.path");
// NOTE: Path.toURL is deprecated (toURI instead) but the URLClassLoader
// unsurprisingly wants URLs, not URIs; so we will use the deprecated
// method which returns URLs for as long as it is available
List<URL> paths = new ArrayList<URL>();
paths.add(new File(dst.toString()).getCanonicalFile().toURL());
JarFile jarFile = new JarFile(dst.toString());
Enumeration<JarEntry> entries = jarFile.entries();
while (entries.hasMoreElements()) {
JarEntry entry = entries.nextElement();
if (entry.getName().matches("/lib/[^/]+\\.jar")) {
File file = new File(System.getProperty("java.io.tmpdir") +
java.io.File.separator +"." + pathPrefix +
"." + className + "." + System.currentTimeMillis() + "." + entry.getName().substring(5));
IOUtils.copyBytes(jarFile.getInputStream(entry), new FileOutputStream(file), conf, true);
file.deleteOnExit();
paths.add(file.toURL());
}
}
StringTokenizer st = new StringTokenizer(cp, File.pathSeparator);
while (st.hasMoreTokens()) {
paths.add((new File(st.nextToken())).getCanonicalFile().toURL());
}
ClassLoader cl = new URLClassLoader(paths.toArray(new URL[]{}),
this.getClass().getClassLoader());
Thread.currentThread().setContextClassLoader(cl);
try {
implClass = cl.loadClass(className);
} catch (ClassNotFoundException e) {
throw new IOException(e);
}
}
return loadInstance(implClass, priority, conf);
}
/**
* @param implClass Implementation class
* @param priority priority
* @param conf configuration
* @throws java.io.IOException Exception
*/
public void load(Class<?> implClass, int priority, Configuration conf)
throws IOException {
E env = loadInstance(implClass, priority, conf);
coprocessors.add(env);
}
/**
* @param implClass Implementation class
* @param priority priority
* @param conf configuration
* @throws java.io.IOException Exception
*/
public E loadInstance(Class<?> implClass, int priority, Configuration conf)
throws IOException {
// create the instance
Coprocessor impl;
Object o = null;
try {
o = implClass.newInstance();
impl = (Coprocessor)o;
} catch (InstantiationException e) {
throw new IOException(e);
} catch (IllegalAccessException e) {
throw new IOException(e);
}
// create the environment
E env = createEnvironment(implClass, impl, priority, ++loadSequence, conf);
if (env instanceof Environment) {
((Environment)env).startup();
}
// HBASE-4014: maintain list of loaded coprocessors for later crash analysis
// if server (master or regionserver) aborts.
coprocessorNames.add(implClass.getName());
return env;
}
/**
* Called when a new Coprocessor class is loaded
*/
public abstract E createEnvironment(Class<?> implClass, Coprocessor instance,
int priority, int sequence, Configuration conf);
public void shutdown(CoprocessorEnvironment e) {
if (e instanceof Environment) {
((Environment)e).shutdown();
} else {
LOG.warn("Shutdown called on unknown environment: "+
e.getClass().getName());
}
}
/**
* Find a coprocessor implementation by class name
* @param className the class name
* @return the coprocessor, or null if not found
*/
public Coprocessor findCoprocessor(String className) {
// initialize the coprocessors
for (E env: coprocessors) {
if (env.getInstance().getClass().getName().equals(className) ||
env.getInstance().getClass().getSimpleName().equals(className)) {
return env.getInstance();
}
}
return null;
}
/**
* Find a coprocessor environment by class name
* @param className the class name
* @return the coprocessor, or null if not found
*/
public CoprocessorEnvironment findCoprocessorEnvironment(String className) {
// initialize the coprocessors
for (E env: coprocessors) {
if (env.getInstance().getClass().getName().equals(className) ||
env.getInstance().getClass().getSimpleName().equals(className)) {
return env;
}
}
return null;
}
/**
* Environment priority comparator.
* Coprocessors are chained in sorted order.
*/
static class EnvironmentPriorityComparator
implements Comparator<CoprocessorEnvironment> {
public int compare(final CoprocessorEnvironment env1,
final CoprocessorEnvironment env2) {
if (env1.getPriority() < env2.getPriority()) {
return -1;
} else if (env1.getPriority() > env2.getPriority()) {
return 1;
}
if (env1.getLoadSequence() < env2.getLoadSequence()) {
return -1;
} else if (env1.getLoadSequence() > env2.getLoadSequence()) {
return 1;
}
return 0;
}
}
/**
* Encapsulation of the environment of each coprocessor
*/
public static class Environment implements CoprocessorEnvironment {
/**
* A wrapper for HTable. Can be used to restrict privilege.
*
* Currently it just helps to track tables opened by a Coprocessor and
* facilitate close of them if it is aborted.
*
* We also disallow row locking.
*
* There is nothing now that will stop a coprocessor from using HTable
* objects directly instead of this API, but in the future we intend to
* analyze coprocessor implementations as they are loaded and reject those
* which attempt to use objects and methods outside the Environment
* sandbox.
*/
class HTableWrapper implements HTableInterface {
private byte[] tableName;
private HTable table;
public HTableWrapper(byte[] tableName) throws IOException {
this.tableName = tableName;
this.table = new HTable(conf, tableName);
openTables.add(this);
}
void internalClose() throws IOException {
table.close();
}
public Configuration getConfiguration() {
return table.getConfiguration();
}
public void close() throws IOException {
try {
internalClose();
} finally {
openTables.remove(this);
}
}
public Result getRowOrBefore(byte[] row, byte[] family)
throws IOException {
return table.getRowOrBefore(row, family);
}
public Result get(Get get) throws IOException {
return table.get(get);
}
public boolean exists(Get get) throws IOException {
return table.exists(get);
}
public void put(Put put) throws IOException {
table.put(put);
}
public void put(List<Put> puts) throws IOException {
table.put(puts);
}
public void delete(Delete delete) throws IOException {
table.delete(delete);
}
public void delete(List<Delete> deletes) throws IOException {
table.delete(deletes);
}
public boolean checkAndPut(byte[] row, byte[] family, byte[] qualifier,
byte[] value, Put put) throws IOException {
return table.checkAndPut(row, family, qualifier, value, put);
}
public boolean checkAndDelete(byte[] row, byte[] family, byte[] qualifier,
byte[] value, Delete delete) throws IOException {
return table.checkAndDelete(row, family, qualifier, value, delete);
}
public long incrementColumnValue(byte[] row, byte[] family,
byte[] qualifier, long amount) throws IOException {
return table.incrementColumnValue(row, family, qualifier, amount);
}
public long incrementColumnValue(byte[] row, byte[] family,
byte[] qualifier, long amount, boolean writeToWAL)
throws IOException {
return table.incrementColumnValue(row, family, qualifier, amount,
writeToWAL);
}
@Override
public Result append(Append append) throws IOException {
return table.append(append);
}
@Override
public Result increment(Increment increment) throws IOException {
return table.increment(increment);
}
public void flushCommits() throws IOException {
table.flushCommits();
}
public boolean isAutoFlush() {
return table.isAutoFlush();
}
public ResultScanner getScanner(Scan scan) throws IOException {
return table.getScanner(scan);
}
public ResultScanner getScanner(byte[] family) throws IOException {
return table.getScanner(family);
}
public ResultScanner getScanner(byte[] family, byte[] qualifier)
throws IOException {
return table.getScanner(family, qualifier);
}
public HTableDescriptor getTableDescriptor() throws IOException {
return table.getTableDescriptor();
}
public byte[] getTableName() {
return tableName;
}
public RowLock lockRow(byte[] row) throws IOException {
throw new RuntimeException(
"row locking is not allowed within the coprocessor environment");
}
public void unlockRow(RowLock rl) throws IOException {
throw new RuntimeException(
"row locking is not allowed within the coprocessor environment");
}
@Override
public void batch(List<? extends Row> actions, Object[] results)
throws IOException, InterruptedException {
table.batch(actions, results);
}
@Override
public Object[] batch(List<? extends Row> actions)
throws IOException, InterruptedException {
return table.batch(actions);
}
@Override
public Result[] get(List<Get> gets) throws IOException {
return table.get(gets);
}
@Override
public <T extends CoprocessorProtocol, R> void coprocessorExec(Class<T> protocol,
byte[] startKey, byte[] endKey, Batch.Call<T, R> callable,
Batch.Callback<R> callback) throws IOException, Throwable {
table.coprocessorExec(protocol, startKey, endKey, callable, callback);
}
@Override
public <T extends CoprocessorProtocol, R> Map<byte[], R> coprocessorExec(
Class<T> protocol, byte[] startKey, byte[] endKey, Batch.Call<T, R> callable)
throws IOException, Throwable {
return table.coprocessorExec(protocol, startKey, endKey, callable);
}
@Override
public <T extends CoprocessorProtocol> T coprocessorProxy(Class<T> protocol,
byte[] row) {
return table.coprocessorProxy(protocol, row);
}
@Override
public void mutateRow(RowMutations rm) throws IOException {
table.mutateRow(rm);
}
}
/** The coprocessor */
public Coprocessor impl;
/** Chaining priority */
protected int priority = Coprocessor.PRIORITY_USER;
/** Current coprocessor state */
Coprocessor.State state = Coprocessor.State.UNINSTALLED;
/** Accounting for tables opened by the coprocessor */
protected List<HTableInterface> openTables =
Collections.synchronizedList(new ArrayList<HTableInterface>());
private int seq;
private Configuration conf;
/**
* Constructor
* @param impl the coprocessor instance
* @param priority chaining priority
*/
public Environment(final Coprocessor impl, final int priority,
final int seq, final Configuration conf) {
this.impl = impl;
this.priority = priority;
this.state = Coprocessor.State.INSTALLED;
this.seq = seq;
this.conf = conf;
}
/** Initialize the environment */
public void startup() {
if (state == Coprocessor.State.INSTALLED ||
state == Coprocessor.State.STOPPED) {
state = Coprocessor.State.STARTING;
try {
impl.start(this);
state = Coprocessor.State.ACTIVE;
} catch (IOException ioe) {
LOG.error("Error starting coprocessor "+impl.getClass().getName(), ioe);
}
} else {
LOG.warn("Not starting coprocessor "+impl.getClass().getName()+
" because not inactive (state="+state.toString()+")");
}
}
/** Clean up the environment */
protected void shutdown() {
if (state == Coprocessor.State.ACTIVE) {
state = Coprocessor.State.STOPPING;
try {
impl.stop(this);
state = Coprocessor.State.STOPPED;
} catch (IOException ioe) {
LOG.error("Error stopping coprocessor "+impl.getClass().getName(), ioe);
}
} else {
LOG.warn("Not stopping coprocessor "+impl.getClass().getName()+
" because not active (state="+state.toString()+")");
}
// clean up any table references
for (HTableInterface table: openTables) {
try {
((HTableWrapper)table).internalClose();
} catch (IOException e) {
// nothing can be done here
LOG.warn("Failed to close " +
Bytes.toStringBinary(table.getTableName()), e);
}
}
}
@Override
public Coprocessor getInstance() {
return impl;
}
@Override
public int getPriority() {
return priority;
}
@Override
public int getLoadSequence() {
return seq;
}
/** @return the coprocessor environment version */
@Override
public int getVersion() {
return Coprocessor.VERSION;
}
/** @return the HBase release */
@Override
public String getHBaseVersion() {
return VersionInfo.getVersion();
}
@Override
public Configuration getConfiguration() {
return conf;
}
/**
* Open a table from within the Coprocessor environment
* @param tableName the table name
* @return an interface for manipulating the table
* @exception java.io.IOException Exception
*/
@Override
public HTableInterface getTable(byte[] tableName) throws IOException {
return new HTableWrapper(tableName);
}
}
protected void abortServer(final String service,
final Server server,
final CoprocessorEnvironment environment,
final Throwable e) {
String coprocessorName = (environment.getInstance()).toString();
server.abort("Aborting service: " + service + " running on : "
+ server.getServerName() + " because coprocessor: "
+ coprocessorName + " threw an exception.", e);
}
protected void abortServer(final CoprocessorEnvironment environment,
final Throwable e) {
String coprocessorName = (environment.getInstance()).toString();
LOG.error("The coprocessor: " + coprocessorName + " threw an unexpected " +
"exception: " + e + ", but there's no specific implementation of " +
" abortServer() for this coprocessor's environment.");
}
/**
* This is used by coprocessor hooks which are declared to throw IOException
* (or its subtypes). For such hooks, we should handle throwable objects
* depending on the Throwable's type. Those which are instances of
* IOException should be passed on to the client. This is in conformance with
* the HBase idiom regarding IOException: that it represents a circumstance
* that should be passed along to the client for its own handling. For
* example, a coprocessor that implements access controls would throw a
* subclass of IOException, such as AccessDeniedException, in its preGet()
* method to prevent an unauthorized client's performing a Get on a particular
* table.
* @param env Coprocessor Environment
* @param e Throwable object thrown by coprocessor.
* @exception IOException Exception
*/
protected void handleCoprocessorThrowable(final CoprocessorEnvironment env,
final Throwable e)
throws IOException {
if (e instanceof IOException) {
throw (IOException)e;
}
// If we got here, e is not an IOException. A loaded coprocessor has a
// fatal bug, and the server (master or regionserver) should remove the
// faulty coprocessor from its set of active coprocessors. Setting
// 'hbase.coprocessor.abortonerror' to true will cause abortServer(),
// which may be useful in development and testing environments where
// 'failing fast' for error analysis is desired.
if (env.getConfiguration().getBoolean("hbase.coprocessor.abortonerror",false)) {
// server is configured to abort.
abortServer(env, e);
} else {
LOG.error("Removing coprocessor '" + env.toString() + "' from " +
"environment because it threw: " + e,e);
coprocessors.remove(env);
throw new DoNotRetryIOException("Coprocessor: '" + env.toString() +
"' threw: '" + e + "' and has been removed" + "from the active " +
"coprocessor set.", e);
}
}
}