org.apache.hama.util.BSPNetUtils.java Source code

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/**
 * 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.hama.util;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ConnectException;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NetworkInterface;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.URI;
import java.net.UnknownHostException;
import java.nio.channels.SocketChannel;
import java.util.HashMap;
import java.util.Map;
import java.util.NoSuchElementException;

import javax.net.SocketFactory;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.SecurityUtil;
import org.apache.hama.Constants;
import org.apache.hama.ipc.Server;

/**
 * NetUtils for our needs.
 */
public class BSPNetUtils {
    public static final Log LOG = LogFactory.getLog(BSPNetUtils.class);

    public static final int MAX_PORT_NUMBER = 65535;

    private static Map<String, String> hostToResolved = new HashMap<String, String>();

    /**
     * Gets the canonical hostname of this machine.
     * 
     * @return String representing host canonical host name
     * @throws UnknownHostException
     */
    public static String getCanonicalHostname() throws UnknownHostException {
        return InetAddress.getLocalHost().getCanonicalHostName();
    }

    /**
     * Uses Minas AvailablePortFinder to find a port, starting at 14000.
     * 
     * @return a free port.
     */
    public static int getFreePort() {
        int startPort = 14000;
        return getFreePort(startPort);
    }

    /**
     * Uses Minas AvailablePortFinder to find a port, starting at startPort.
     * 
     * @return a free port.
     */
    public static int getFreePort(int pStartPort) {
        int startPort = pStartPort;
        while (!available(startPort)) {
            startPort++;
        }
        return startPort;
    }

    /**
     * Gets a new InetSocketAddress from the given peerName. peerName must contain
     * a colon to distinct between host and port.
     * 
     * @param peerName the name as a String of the BSP peer to get the address
     *          from
     * @return the InetSocketAddress of the given BSP peer
     */
    public static InetSocketAddress getAddress(String peerName) {
        int index = peerName.lastIndexOf(':');
        if (index <= 0 || index == peerName.length() - 1) {
            throw new ArrayIndexOutOfBoundsException("Invalid host and port information. "
                    + "Peername must consist of atleast ONE \":\"! " + "Given peername was: " + peerName);
        }
        return new InetSocketAddress(peerName.substring(0, index), Integer.valueOf(peerName.substring(index + 1)));
    }

    /**
     * Checks to see if a specific port is available.
     * 
     * @param port the port to check for availability
     */
    public static boolean available(int port) {
        if (port < 1000 || port > MAX_PORT_NUMBER) {
            throw new IllegalArgumentException("Invalid start port: " + port);
        }

        ServerSocket ss = null;
        DatagramSocket ds = null;
        try {
            ss = new ServerSocket(port);
            ss.setReuseAddress(true);
            ds = new DatagramSocket(port);
            ds.setReuseAddress(true);
            return true;
        } catch (IOException e) {
        } finally {
            if (ds != null) {
                ds.close();
            }

            if (ss != null) {
                try {
                    ss.close();
                } catch (IOException e) {
                    /* should not be thrown */
                }
            }
        }

        return false;
    }

    public static int getNextAvailable(int fromPort) {
        if ((fromPort < Constants.DEFAULT_PEER_PORT) || (fromPort > MAX_PORT_NUMBER)) {
            throw new IllegalArgumentException("Invalid start port: " + fromPort);
        }

        for (int i = fromPort + 1; i <= MAX_PORT_NUMBER; i++) {
            if (available(i)) {
                return i;
            }
        }

        throw new NoSuchElementException("Could not find an available port " + "above " + fromPort);
    }

    /**
     * Returns InetSocketAddress that a client can use to connect to the server.
     * Server.getListenerAddress() is not correct when the server binds to
     * "0.0.0.0". This returns "127.0.0.1:port" when the getListenerAddress()
     * returns "0.0.0.0:port".
     * 
     * @param server
     * @return socket address that a client can use to connect to the server.
     */
    public static InetSocketAddress getConnectAddress(Server server) {
        InetSocketAddress addr = server.getListenerAddress();
        if (addr.getAddress().isAnyLocalAddress()) {
            addr = makeSocketAddr("127.0.0.1", addr.getPort());
        }
        return addr;
    }

    /**
     * Create a socket address with the given host and port. The hostname might be
     * replaced with another host that was set via
     * {@link NetUtils#addStaticResolution(String, String)}. The value of
     * hadoop.security.token.service.use_ip will determine whether the standard
     * java host resolver is used, or if the fully qualified resolver is used.
     * 
     * @param host the hostname or IP use to instantiate the object
     * @param port the port number
     * @return InetSocketAddress
     */
    public static InetSocketAddress makeSocketAddr(String host, int port) {
        String staticHost = getStaticResolution(host);
        String resolveHost = (staticHost != null) ? staticHost : host;

        InetSocketAddress addr;
        try {
            InetAddress iaddr = SecurityUtil.getByName(resolveHost);
            // if there is a static entry for the host, make the returned
            // address look like the original given host
            if (staticHost != null) {
                iaddr = InetAddress.getByAddress(host, iaddr.getAddress());
            }
            addr = new InetSocketAddress(iaddr, port);
        } catch (UnknownHostException e) {
            addr = InetSocketAddress.createUnresolved(host, port);
        }
        return addr;
    }

    /**
     * Retrieves the resolved name for the passed host. The resolved name must
     * have been set earlier using
     * {@link NetUtils#addStaticResolution(String, String)}
     * 
     * @param host
     * @return the resolution
     */
    public static String getStaticResolution(String host) {
        synchronized (hostToResolved) {
            return hostToResolved.get(host);
        }
    }

    /**
     * Handle the transition from pairs of attributes specifying a host and port
     * to a single colon separated one.
     * 
     * @param conf the configuration to check
     * @param oldBindAddressName the old address attribute name
     * @param oldPortName the old port attribute name
     * @param newBindAddressName the new combined name
     * @return the complete address from the configuration
     */
    public static String getServerAddress(Configuration conf, String oldBindAddressName, String oldPortName,
            String newBindAddressName) {
        String oldAddr = conf.get(oldBindAddressName);
        String oldPort = conf.get(oldPortName);
        String newAddrPort = conf.get(newBindAddressName);
        if (oldAddr == null && oldPort == null) {
            return newAddrPort;
        }
        String[] newAddrPortParts = newAddrPort.split(":", 2);
        if (newAddrPortParts.length != 2) {
            throw new IllegalArgumentException("Invalid address/port: " + newAddrPort);
        }
        if (oldAddr == null) {
            oldAddr = newAddrPortParts[0];
        } else {
            LOG.warn("Configuration parameter " + oldBindAddressName + " is deprecated. Use " + newBindAddressName
                    + " instead.");
        }
        if (oldPort == null) {
            oldPort = newAddrPortParts[1];
        } else {
            LOG.warn("Configuration parameter " + oldPortName + " is deprecated. Use " + newBindAddressName
                    + " instead.");
        }
        return oldAddr + ":" + oldPort;
    }

    /**
     * Util method to build socket addr from either: <host>:<post>
     * <fs>://<host>:<port>/<path>
     */
    public static InetSocketAddress createSocketAddr(String target) {
        return createSocketAddr(target, -1);
    }

    /**
     * Util method to build socket addr from either: <host> <host>:<post>
     * <fs>://<host>:<port>/<path>
     */
    public static InetSocketAddress createSocketAddr(String target, int defaultPort) {
        if (target == null) {
            throw new IllegalArgumentException("Socket address is null");
        }
        boolean hasScheme = target.contains("://");
        URI uri = null;
        try {
            uri = hasScheme ? URI.create(target) : URI.create("dummyscheme://" + target);
        } catch (IllegalArgumentException e) {
            throw new IllegalArgumentException("Does not contain a valid host:port authority: " + target);
        }

        String host = uri.getHost();
        int port = uri.getPort();
        if (port == -1) {
            port = defaultPort;
        }
        String path = uri.getPath();

        if ((host == null) || (port < 0) || (!hasScheme && path != null && !path.isEmpty())) {
            throw new IllegalArgumentException("Does not contain a valid host:port authority: " + target);
        }
        return makeSocketAddr(host, port);
    }

    /**
     * Checks if {@code host} is a local host name and return {@link InetAddress}
     * corresponding to that address.
     * 
     * @param host the specified host
     * @return a valid local {@link InetAddress} or null
     * @throws SocketException if an I/O error occurs
     */
    public static InetAddress getLocalInetAddress(String host) throws SocketException {
        if (host == null) {
            return null;
        }
        InetAddress addr = null;
        try {
            addr = InetAddress.getByName(host);
            if (NetworkInterface.getByInetAddress(addr) == null) {
                addr = null; // Not a local address
            }
        } catch (UnknownHostException ignore) {
        }
        return addr;
    }

    /**
     * This is a drop-in replacement for
     * {@link Socket#connect(SocketAddress, int)}. In the case of normal sockets
     * that don't have associated channels, this just invokes
     * <code>socket.connect(endpoint, timeout)</code>. If
     * <code>socket.getChannel()</code> returns a non-null channel, connect is
     * implemented using Hadoop's selectors. This is done mainly to avoid Sun's
     * connect implementation from creating thread-local selectors, since Hadoop
     * does not have control on when these are closed and could end up taking all
     * the available file descriptors.
     * 
     * @see java.net.Socket#connect(java.net.SocketAddress, int)
     * 
     * @param socket
     * @param address the remote address
     * @param timeout timeout in milliseconds
     */
    public static void connect(Socket socket, SocketAddress address, int timeout) throws IOException {
        connect(socket, address, null, timeout);
    }

    /**
     * Like {@link NetUtils#connect(Socket, SocketAddress, int)} but also takes a
     * local address and port to bind the socket to.
     * 
     * @param socket
     * @param endpoint the remote address
     * @param localAddr the local address to bind the socket to
     * @param timeout timeout in milliseconds
     */
    public static void connect(Socket socket, SocketAddress endpoint, SocketAddress localAddr, int timeout)
            throws IOException {
        if (socket == null || endpoint == null || timeout < 0) {
            throw new IllegalArgumentException("Illegal argument for connect()");
        }

        SocketChannel ch = socket.getChannel();

        if (localAddr != null) {
            socket.bind(localAddr);
        }

        if (ch == null) {
            // let the default implementation handle it.
            socket.connect(endpoint, timeout);
        } else {
            SocketIOWithTimeout.connect(ch, endpoint, timeout);
        }

        // There is a very rare case allowed by the TCP specification, such that
        // if we are trying to connect to an endpoint on the local machine,
        // and we end up choosing an ephemeral port equal to the destination port,
        // we will actually end up getting connected to ourself (ie any data we
        // send just comes right back). This is only possible if the target
        // daemon is down, so we'll treat it like connection refused.
        if (socket.getLocalPort() == socket.getPort() && socket.getLocalAddress().equals(socket.getInetAddress())) {
            LOG.info("Detected a loopback TCP socket, disconnecting it");
            socket.close();
            throw new ConnectException("Localhost targeted connection resulted in a loopback. "
                    + "No daemon is listening on the target port.");
        }
    }

    /**
     * Same as getInputStream(socket, socket.getSoTimeout()).<br>
     * <br>
     * 
     * From documentation for {@link #getInputStream(Socket, long)}:<br>
     * Returns InputStream for the socket. If the socket has an associated
     * SocketChannel then it returns a {@link SocketInputStream} with the given
     * timeout. If the socket does not have a channel,
     * {@link Socket#getInputStream()} is returned. In the later case, the timeout
     * argument is ignored and the timeout set with
     * {@link Socket#setSoTimeout(int)} applies for reads.<br>
     * <br>
     * 
     * Any socket created using socket factories returned by {@link NetUtils},
     * must use this interface instead of {@link Socket#getInputStream()}.
     * 
     * @see #getInputStream(Socket, long)
     * 
     * @param socket
     * @return InputStream for reading from the socket.
     * @throws IOException
     */
    public static InputStream getInputStream(Socket socket) throws IOException {
        return getInputStream(socket, socket.getSoTimeout());
    }

    /**
     * Returns InputStream for the socket. If the socket has an associated
     * SocketChannel then it returns a {@link SocketInputStream} with the given
     * timeout. If the socket does not have a channel,
     * {@link Socket#getInputStream()} is returned. In the later case, the timeout
     * argument is ignored and the timeout set with
     * {@link Socket#setSoTimeout(int)} applies for reads.<br>
     * <br>
     * 
     * Any socket created using socket factories returned by {@link NetUtils},
     * must use this interface instead of {@link Socket#getInputStream()}.
     * 
     * @see Socket#getChannel()
     * 
     * @param socket
     * @param timeout timeout in milliseconds. This may not always apply. zero for
     *          waiting as long as necessary.
     * @return InputStream for reading from the socket.
     * @throws IOException
     */
    public static InputStream getInputStream(Socket socket, long timeout) throws IOException {
        return (socket.getChannel() == null) ? socket.getInputStream() : new SocketInputStream(socket, timeout);
    }

    /**
     * Same as getOutputStream(socket, 0). Timeout of zero implies write will wait
     * until data is available.<br>
     * <br>
     * 
     * From documentation for {@link #getOutputStream(Socket, long)} : <br>
     * Returns OutputStream for the socket. If the socket has an associated
     * SocketChannel then it returns a {@link SocketOutputStream} with the given
     * timeout. If the socket does not have a channel,
     * {@link Socket#getOutputStream()} is returned. In the later case, the
     * timeout argument is ignored and the write will wait until data is
     * available.<br>
     * <br>
     * 
     * Any socket created using socket factories returned by {@link NetUtils},
     * must use this interface instead of {@link Socket#getOutputStream()}.
     * 
     * @see #getOutputStream(Socket, long)
     * 
     * @param socket
     * @return OutputStream for writing to the socket.
     * @throws IOException
     */
    public static OutputStream getOutputStream(Socket socket) throws IOException {
        return getOutputStream(socket, 0);
    }

    /**
     * Returns OutputStream for the socket. If the socket has an associated
     * SocketChannel then it returns a {@link SocketOutputStream} with the given
     * timeout. If the socket does not have a channel,
     * {@link Socket#getOutputStream()} is returned. In the later case, the
     * timeout argument is ignored and the write will wait until data is
     * available.<br>
     * <br>
     * 
     * Any socket created using socket factories returned by {@link NetUtils},
     * must use this interface instead of {@link Socket#getOutputStream()}.
     * 
     * @see Socket#getChannel()
     * 
     * @param socket
     * @param timeout timeout in milliseconds. This may not always apply. zero for
     *          waiting as long as necessary.
     * @return OutputStream for writing to the socket.
     * @throws IOException
     */
    public static OutputStream getOutputStream(Socket socket, long timeout) throws IOException {
        return (socket.getChannel() == null) ? socket.getOutputStream() : new SocketOutputStream(socket, timeout);
    }

    /**
     * Get the default socket factory as specified by the configuration parameter
     * <tt>hadoop.rpc.socket.factory.default</tt>
     * 
     * @param conf the configuration
     * @return the default socket factory as specified in the configuration or the
     *         JVM default socket factory if the configuration does not contain a
     *         default socket factory property.
     */
    public static SocketFactory getDefaultSocketFactory(Configuration conf) {

        String propValue = conf.get("hadoop.rpc.socket.factory.class.default");
        if ((propValue == null) || (propValue.length() == 0))
            return SocketFactory.getDefault();

        return getSocketFactoryFromProperty(conf, propValue);
    }

    /**
     * Get the socket factory corresponding to the given proxy URI. If the given
     * proxy URI corresponds to an absence of configuration parameter, returns
     * null. If the URI is malformed raises an exception.
     * 
     * @param propValue the property which is the class name of the SocketFactory
     *          to instantiate; assumed non null and non empty.
     * @return a socket factory as defined in the property value.
     */
    public static SocketFactory getSocketFactoryFromProperty(Configuration conf, String propValue) {

        try {
            Class<?> theClass = conf.getClassByName(propValue);
            return (SocketFactory) org.apache.hadoop.util.ReflectionUtils.newInstance(theClass, conf);

        } catch (ClassNotFoundException cnfe) {
            throw new RuntimeException("Socket Factory class not found: " + cnfe);
        }
    }
}