/*
* Copyright (C) 2015 higherfrequencytrading.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see .
*/
package net.openhft.chronicle.map;
import net.openhft.chronicle.hash.impl.util.BuildVersion;
import net.openhft.chronicle.hash.replication.ConnectionListener;
import net.openhft.chronicle.hash.replication.RemoteNodeValidator;
import net.openhft.chronicle.hash.replication.TcpTransportAndNetworkConfig;
import net.openhft.chronicle.hash.replication.ThrottlingConfig;
import net.openhft.chronicle.hash.serialization.internal.SerializationBuilder;
import net.openhft.lang.collection.ATSDirectBitSet;
import net.openhft.lang.collection.DirectBitSet;
import net.openhft.lang.io.ByteBufferBytes;
import net.openhft.lang.io.Bytes;
import net.openhft.lang.io.DirectStore;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Closeable;
import java.io.IOException;
import java.net.*;
import java.nio.BufferUnderflowException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.channels.*;
import java.util.BitSet;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import static java.nio.channels.SelectionKey.*;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static net.openhft.chronicle.hash.impl.util.BuildVersion.version;
import static net.openhft.lang.MemoryUnit.*;
interface Work {
/**
* @param in the buffer that we will fill up
* @return true when all the work is complete
*/
boolean doWork(@NotNull Bytes in);
}
/**
* Used with a {@link net.openhft.chronicle.map.ReplicatedChronicleMap} to send data between the
* maps using a socket connection {@link net.openhft.chronicle.map.TcpReplicator}
*
* @author Rob Austin.
*/
public final class TcpReplicator extends AbstractChannelReplicator implements Closeable {
public static final long TIMESTAMP_FACTOR = 10000;
private static final int STATELESS_CLIENT = -127;
private static final byte HEARTBEAT = 0;
private static final byte NOT_SET = 0;//(byte) HEARTBEAT.ordinal();
private static final Logger LOG = LoggerFactory.getLogger(TcpReplicator.class.getName());
private static final int BUFFER_SIZE = 0x100000; // 1MB
public static final long SPIN_LOOP_TIME_IN_NONOSECONDS = TimeUnit.MICROSECONDS.toNanos(500);
private final SelectionKey[] selectionKeysStore = new SelectionKey[Byte.MAX_VALUE + 1];
// used to instruct the selector thread to set OP_WRITE on a key correlated by the bit index
// in the bitset
private final KeyInterestUpdater opWriteUpdater =
new KeyInterestUpdater(OP_WRITE, selectionKeysStore);
private final BitSet activeKeys = new BitSet(selectionKeysStore.length);
private final long heartBeatIntervalMillis;
private final ConnectionListener connectionListener;
private long largestEntrySoFar = 128;
@NotNull
private final Replica replica;
private final byte localIdentifier;
@NotNull
private final Replica.EntryExternalizable externalizable;
@NotNull
private final TcpTransportAndNetworkConfig replicationConfig;
private final
@Nullable
RemoteNodeValidator remoteNodeValidator;
private final String name;
private long selectorTimeout;
/**
* @throws IOException on an io error.
*/
public TcpReplicator(@NotNull final Replica replica,
@NotNull final Replica.EntryExternalizable externalizable,
@NotNull final TcpTransportAndNetworkConfig replicationConfig,
@Nullable final RemoteNodeValidator remoteNodeValidator,
String name,
@Nullable final ConnectionListener connectionListener)
throws IOException {
super("TcpSocketReplicator-" + replica.identifier(), replicationConfig.throttlingConfig());
final ThrottlingConfig throttlingConfig = replicationConfig.throttlingConfig();
long throttleBucketInterval = throttlingConfig.bucketInterval(MILLISECONDS);
heartBeatIntervalMillis = replicationConfig.heartBeatInterval(MILLISECONDS);
selectorTimeout = Math.min(heartBeatIntervalMillis / 4, throttleBucketInterval);
this.replica = replica;
this.localIdentifier = replica.identifier();
this.externalizable = externalizable;
this.replicationConfig = replicationConfig;
this.connectionListener = connectionListener;
this.remoteNodeValidator = remoteNodeValidator;
this.name = name;
start();
}
@Override
void processEvent() throws IOException {
try {
final InetSocketAddress serverInetSocketAddress =
new InetSocketAddress(replicationConfig.serverPort());
final Details serverDetails = new Details(serverInetSocketAddress, localIdentifier);
new ServerConnector(serverDetails).connect();
for (InetSocketAddress client : replicationConfig.endpoints()) {
final Details clientDetails = new Details(client, localIdentifier);
new ClientConnector(clientDetails).connect();
}
while (selector.isOpen()) {
registerPendingRegistrations();
final int nSelectedKeys = select();
// its less resource intensive to set this less frequently and use an approximation
final long approxTime = System.currentTimeMillis();
checkThrottleInterval();
// check that we have sent and received heartbeats
heartBeatMonitor(approxTime);
// set the OP_WRITE when data is ready to send
opWriteUpdater.applyUpdates();
if (useJavaNIOSelectionKeys) {
// use the standard java nio selector
if (nSelectedKeys == 0)
continue; // go back and check pendingRegistrations
final Set selectionKeys = selector.selectedKeys();
for (final SelectionKey key : selectionKeys) {
processKey(approxTime, key);
}
selectionKeys.clear();
} else {
// use the netty like selector
final SelectionKey[] keys = selectedKeys.flip();
try {
for (int i = 0; i < keys.length && keys[i] != null; i++) {
final SelectionKey key = keys[i];
try {
processKey(approxTime, key);
} catch (BufferUnderflowException e) {
if (!isClosed)
LOG.error("", e);
}
}
} finally {
for (int i = 0; i < keys.length && keys[i] != null; i++) {
keys[i] = null;
}
}
}
}
} catch (CancelledKeyException | ConnectException | ClosedChannelException |
ClosedSelectorException e) {
if (LOG.isDebugEnabled())
LOG.debug("", e);
} catch (Exception e) {
LOG.error("", e);
} catch (Throwable e) {
LOG.error("", e);
throw e;
} finally {
if (LOG.isDebugEnabled())
LOG.debug("closing name=" + name);
if (!isClosed) {
closeResources();
}
}
}
private void processKey(long approxTime, @NotNull SelectionKey key) {
try {
if (!key.isValid())
return;
if (key.isAcceptable()) {
if (LOG.isDebugEnabled())
LOG.debug("onAccept - " + name);
onAccept(key);
}
if (key.isConnectable()) {
if (LOG.isDebugEnabled())
LOG.debug("onConnect - " + name);
onConnect(key);
}
if (key.isReadable()) {
if (LOG.isDebugEnabled())
LOG.debug("onRead - " + name);
onRead(key, approxTime);
}
if (key.isWritable()) {
if (LOG.isDebugEnabled())
LOG.debug("onWrite - " + name);
onWrite(key, approxTime);
}
} catch (InterruptedException e) {
quietClose(key, e);
} catch (BufferUnderflowException | IOException |
ClosedSelectorException | CancelledKeyException e) {
if (!isClosed)
quietClose(key, e);
} catch (Exception e) {
LOG.info("", e);
if (!isClosed)
closeEarlyAndQuietly(key.channel());
}
}
/**
* spin loops 100000 times first before calling the selector with timeout
*
* @return The number of keys, possibly zero, whose ready-operation sets were updated
* @throws IOException
*/
private int select() throws IOException {
long start = System.nanoTime();
while (System.nanoTime() < start + SPIN_LOOP_TIME_IN_NONOSECONDS) {
final int keys = selector.selectNow();
if (keys != 0)
return keys;
}
return selector.select(selectorTimeout);
}
/**
* checks that we receive heartbeats and send out heart beats.
*
* @param approxTime the approximate time in milliseconds
*/
void heartBeatMonitor(long approxTime) {
for (int i = activeKeys.nextSetBit(0); i >= 0; i = activeKeys.nextSetBit(i + 1)) {
try {
final SelectionKey key = selectionKeysStore[i];
if (!key.isValid() || !key.channel().isOpen()) {
activeKeys.clear(i);
continue;
}
final Attached attachment = (Attached) key.attachment();
if (attachment == null)
continue;
if (!attachment.hasRemoteHeartbeatInterval)
continue;
try {
sendHeartbeatIfRequired(approxTime, key);
} catch (Exception e) {
if (LOG.isDebugEnabled())
LOG.debug("", e);
}
try {
heartbeatCheckHasReceived(key, approxTime);
} catch (Exception e) {
if (LOG.isDebugEnabled())
LOG.debug("", e);
}
} catch (Exception e) {
if (LOG.isDebugEnabled())
LOG.debug("", e);
}
}
}
/**
* check to see if its time to send a heartbeat, and send one if required
*
* @param approxTime the current time ( approximately )
* @param key nio selection key
*/
private void sendHeartbeatIfRequired(final long approxTime,
@NotNull final SelectionKey key) {
final Attached attachment = (Attached) key.attachment();
if (attachment.isHandShakingComplete() && attachment.entryWriter.lastSentTime +
heartBeatIntervalMillis < approxTime) {
attachment.entryWriter.lastSentTime = approxTime;
attachment.entryWriter.writeHeartbeatToBuffer();
enableOpWrite(key);
if (LOG.isDebugEnabled())
LOG.debug("sending heartbeat");
}
}
private void enableOpWrite(@NotNull SelectionKey key) {
int ops = key.interestOps();
if ((ops & (OP_CONNECT | OP_ACCEPT)) == 0)
key.interestOps(ops | OP_WRITE);
}
/**
* check to see if we have lost connection with the remote node and if we have attempts a
* reconnect.
*
* @param key the key relating to the heartbeat that we are checking
* @param approxTimeOutTime the approximate time in milliseconds
* @throws ConnectException
*/
private void heartbeatCheckHasReceived(@NotNull final SelectionKey key,
final long approxTimeOutTime) {
final Attached attached = (Attached) key.attachment();
// we wont attempt to reconnect the server socket
if (attached.isServer || !attached.isHandShakingComplete())
return;
final SocketChannel channel = (SocketChannel) key.channel();
if (approxTimeOutTime >
attached.entryReader.lastHeartBeatReceived + attached.remoteHeartbeatInterval) {
if (LOG.isDebugEnabled())
LOG.debug("lost connection, attempting to reconnect. " +
"missed heartbeat from identifier=" + attached.remoteIdentifier);
activeKeys.clear(attached.remoteIdentifier);
closeables.closeQuietly(channel.socket());
// when node discovery is used ( by nodes broadcasting out their host:port over UDP ),
// when new or restarted nodes are started up. they attempt to find the nodes
// on the grid by listening to the host and ports of the other nodes, so these nodes
// will establish the connection when they come back up, hence under these
// circumstances, polling a dropped node to attempt to reconnect is no-longer
// required as the remote node will establish the connection its self on startup.
if (replicationConfig.autoReconnectedUponDroppedConnection())
attached.connector.connectLater();
}
}
/**
* closes and only logs the exception at debug
*
* @param key the SelectionKey
* @param e the Exception that caused the issue
*/
private void quietClose(@NotNull final SelectionKey key, @NotNull final Exception e) {
if (LOG.isDebugEnabled())
LOG.debug("", e);
// todo OZAN :
// null check (Attached)key.attachment();
// connectionListener.onDiconnect( ((SocketChannel)key.channel()).socket().getInetAddress(), ((Attached)key.attachment()).remoteIdentifier);
closeEarlyAndQuietly(key.channel());
}
/**
* called when the selector receives a OP_CONNECT message
*/
private void onConnect(@NotNull final SelectionKey key)
throws IOException {
SocketChannel channel = null;
try {
channel = (SocketChannel) key.channel();
} finally {
closeables.add(channel);
}
final Attached attached = (Attached) key.attachment();
try {
if (!channel.finishConnect()) {
return;
}
} catch (SocketException e) {
quietClose(key, e);
// when node discovery is used ( by nodes broadcasting out their host:port over UDP ),
// when new or restarted nodes are started up. they attempt to find the nodes
// on the grid by listening to the host and ports of the other nodes,
// so these nodes will establish the connection when they come back up,
// hence under these circumstances, polling a dropped node to attempt to reconnect
// is no-longer required as the remote node will establish the connection its self
// on startup.
attached.connector.connectLater();
throw e;
}
attached.connector.setSuccessfullyConnected();
if (LOG.isDebugEnabled())
LOG.debug("successfully connected to {}, local-id={}",
channel.socket().getInetAddress(), localIdentifier);
channel.configureBlocking(false);
channel.socket().setTcpNoDelay(true);
channel.socket().setSoTimeout(0);
channel.socket().setSoLinger(false, 0);
attached.entryReader = new TcpSocketChannelEntryReader();
attached.entryWriter = new TcpSocketChannelEntryWriter();
key.interestOps(OP_WRITE | OP_READ);
throttle(channel);
// register it with the selector and store the ModificationIterator for this key
attached.entryWriter.identifierToBuffer(localIdentifier);
}
/**
* called when the selector receives a OP_ACCEPT message
*/
private void onAccept(@NotNull final SelectionKey key) throws IOException {
ServerSocketChannel server = null;
try {
server = (ServerSocketChannel) key.channel();
} finally {
if (server != null)
closeables.add(server);
}
SocketChannel channel = null;
try {
channel = server.accept();
} finally {
if (channel != null)
closeables.add(channel);
}
channel.configureBlocking(false);
channel.socket().setReuseAddress(true);
channel.socket().setTcpNoDelay(true);
channel.socket().setSoTimeout(0);
channel.socket().setSoLinger(false, 0);
final Attached attached = new Attached();
attached.entryReader = new TcpSocketChannelEntryReader();
attached.entryWriter = new TcpSocketChannelEntryWriter();
attached.entryWriter.identifierToBuffer(localIdentifier);
attached.isServer = true;
channel.register(selector, OP_READ, attached);
throttle(channel);
}
/**
* check that the version number is valid text,
*
* @param versionNumber the version number to check
* @return true, if the version number looks correct
*/
boolean isValidVersionNumber(String versionNumber) {
if (versionNumber.length()<=2)
return false;
for (char c : versionNumber.toCharArray()) {
if (c >= '0' && c <= '9')
continue;
if (c == '.' || c == '-' || c == '_')
continue;
if (c >= 'A' && c <= 'Z')
continue;
if (c >= 'a' && c <= 'z')
continue;
return false;
}
return true;
}
private void checkVersions(final Attached attached) {
final String localVersion = BuildVersion.version();
final String remoteVersion = attached.serverVersion;
if (!remoteVersion.equals(localVersion)) {
byte remoteIdentifier = attached.remoteIdentifier;
LOG.warn("DIFFERENT CHRONICLE-MAP VERSIONS : " +
"local-map=" + localVersion +
", remote-map-id-" + remoteIdentifier + "=" +
remoteVersion +
", The Remote Chronicle Map with " +
"identifier=" + remoteIdentifier +
" and this Chronicle Map are on different " +
"versions, we suggest that you use the same version."
);
}
}
/**
* used to exchange identifiers and timestamps and heartbeat intervals between the server and
* client
*
* @param key the SelectionKey relating to the this cha
* @param socketChannel
* @throws java.io.IOException
* @throws InterruptedException
*/
private void doHandShaking(@NotNull final SelectionKey key,
@NotNull SocketChannel socketChannel)
throws IOException {
final Attached attached = (Attached) key.attachment();
final TcpSocketChannelEntryWriter writer = attached.entryWriter;
final TcpSocketChannelEntryReader reader = attached.entryReader;
socketChannel.register(selector, OP_READ | OP_WRITE, attached);
if (attached.remoteIdentifier == Byte.MIN_VALUE) {
final byte remoteIdentifier = reader.identifierFromBuffer();
if (remoteIdentifier == STATELESS_CLIENT) {
attached.handShakingComplete = true;
attached.hasRemoteHeartbeatInterval = false;
return;
}
if (remoteIdentifier == Byte.MIN_VALUE)
return;
attached.remoteIdentifier = remoteIdentifier;
// todo OZAN : add call to onConnectedListener.
//connectionListener. onConnected(channel.socket().getInetAddress() , attached
// .remoteIdentifier, attached.isServer );
// we use the as iterating the activeKeys via the bitset wont create and Objects
// but if we use the selector.keys() this will.
selectionKeysStore[remoteIdentifier] = key;
activeKeys.set(remoteIdentifier);
if (LOG.isDebugEnabled()) {
LOG.debug("server-connection id={}, remoteIdentifier={}", localIdentifier,
remoteIdentifier);
}
// this can occur sometimes when if 2 or more remote node attempt to use node discovery
// at the same time
final SocketAddress remoteAddress = socketChannel.getRemoteAddress();
if ((remoteNodeValidator != null &&
!remoteNodeValidator.validate(remoteIdentifier, remoteAddress))
|| remoteIdentifier == localIdentifier)
// throwing this exception will cause us to disconnect, both the client and server
// will be able to detect the the remote and local identifiers are the same,
// as the identifier is send early on in the hand shaking via the connect(()
// and accept() methods
throw new IllegalStateException("dropping connection, " +
"as the remote-identifier is already being used, identifier=" +
remoteIdentifier);
if (LOG.isDebugEnabled())
LOG.debug("handshaking for localIdentifier=" + localIdentifier + "," +
"remoteIdentifier=" + remoteIdentifier);
attached.remoteModificationIterator =
replica.acquireModificationIterator(remoteIdentifier);
attached.remoteModificationIterator.setModificationNotifier(attached);
writer.writeRemoteBootstrapTimestamp(replica.lastModificationTime(remoteIdentifier));
writer.writeServerVersion();
// tell the remote node, what are heartbeat interval is
writer.writeRemoteHeartbeatInterval(heartBeatIntervalMillis);
}
if (attached.remoteBootstrapTimestamp == Long.MIN_VALUE) {
attached.remoteBootstrapTimestamp = reader.remoteBootstrapTimestamp();
if (attached.remoteBootstrapTimestamp == Long.MIN_VALUE)
return;
}
if (attached.serverVersion == null) {
try {
attached.serverVersion = reader.readRemoteServerVersion();
} catch (IllegalStateException e1) {
socketChannel.close();
return;
}
if (attached.serverVersion == null)
return;
if (!isValidVersionNumber(attached.serverVersion)) {
LOG.warn("Closing the remote connection : Please check that you don't have " +
"a third party system incorrectly connecting to ChronicleMap, " +
"remoteAddress=" + socketChannel.getRemoteAddress() + ", " +
"so closing the remote connection as Chronicle can not make sense " +
"of the remote version number received from the external connection, " +
"version=" + attached.serverVersion + ", " +
"Chronicle is expecting the version number to only contain " +
"'.','-', ,A-Z,a-z,0-9");
socketChannel.close();
return;
}
checkVersions(attached);
}
if (!attached.hasRemoteHeartbeatInterval) {
final long value = reader.readRemoteHeartbeatIntervalFromBuffer();
if (value == Long.MIN_VALUE)
return;
if (value < 0) {
LOG.error("value=" + value);
}
// we add a 10% safety margin to the timeout time due to latency fluctuations
// on the network, in other words we wont consider a connection to have
// timed out, unless the heartbeat interval has exceeded 25% of the expected time.
attached.remoteHeartbeatInterval = (long) (value * 1.25);
// we have to make our selector poll interval at least as short as the minimum selector
// timeout
selectorTimeout = Math.min(selectorTimeout, value);
if (selectorTimeout < 0)
LOG.info("");
attached.hasRemoteHeartbeatInterval = true;
// now we're finished we can get on with reading the entries
attached.remoteModificationIterator.dirtyEntries(attached.remoteBootstrapTimestamp);
try {
reader.entriesFromBuffer(attached, key);
} finally {
attached.handShakingComplete = true;
}
}
}
/**
* called when the selector receives a OP_WRITE message
*/
private void onWrite(@NotNull final SelectionKey key,
final long approxTime) throws IOException {
final SocketChannel socketChannel = (SocketChannel) key.channel();
final Attached attached = (Attached) key.attachment();
if (attached == null) {
LOG.info("Closing connection " + socketChannel + ", nothing attached");
socketChannel.close();
return;
}
TcpSocketChannelEntryWriter entryWriter = attached.entryWriter;
if (entryWriter == null) throw
new NullPointerException("No entryWriter");
if (entryWriter.isWorkIncomplete()) {
final boolean completed = entryWriter.doWork();
if (completed)
entryWriter.workCompleted();
} else if (attached.remoteModificationIterator != null)
entryWriter.entriesToBuffer(attached.remoteModificationIterator);
try {
final int len = entryWriter.writeBufferToSocket(socketChannel, approxTime);
if (len == -1)
socketChannel.close();
if (len > 0)
contemplateThrottleWrites(len);
if (!entryWriter.hasBytesToWrite()
&& !entryWriter.isWorkIncomplete()
&& !hasNext(attached)
&& attached.isHandShakingComplete()) {
// if we have no more data to write to the socket then we will
// un-register OP_WRITE on the selector, until more data becomes available
// The OP_WRITE will get added back in as soon as we have data to write
if (LOG.isDebugEnabled())
LOG.debug("Disabling OP_WRITE to remoteIdentifier=" +
attached.remoteIdentifier +
", localIdentifier=" + localIdentifier);
key.interestOps(key.interestOps() & ~OP_WRITE);
}
} catch (IOException e) {
quietClose(key, e);
if (!attached.isServer)
attached.connector.connectLater();
throw e;
}
}
private boolean hasNext(Attached attached) {
return attached.remoteModificationIterator != null
&& attached.remoteModificationIterator.hasNext();
}
/**
* called when the selector receives a OP_READ message
*/
private void onRead(@NotNull final SelectionKey key,
final long approxTime) throws IOException, InterruptedException {
final SocketChannel socketChannel = (SocketChannel) key.channel();
final Attached attached = (Attached) key.attachment();
if (attached == null) {
LOG.info("Closing connection " + socketChannel + ", nothing attached");
socketChannel.close();
return;
}
try {
int len = attached.entryReader.readSocketToBuffer(socketChannel);
if (len == -1) {
socketChannel.register(selector, 0);
if (replicationConfig.autoReconnectedUponDroppedConnection()) {
AbstractConnector connector = attached.connector;
if (connector != null)
connector.connectLater();
} else
socketChannel.close();
return;
}
if (len == 0)
return;
if (attached.entryWriter.isWorkIncomplete())
return;
} catch (IOException e) {
if (!attached.isServer)
attached.connector.connectLater();
throw e;
}
if (LOG.isDebugEnabled())
LOG.debug("heartbeat or data received.");
attached.entryReader.lastHeartBeatReceived = approxTime;
if (attached.isHandShakingComplete()) {
attached.entryReader.entriesFromBuffer(attached, key);
} else {
doHandShaking(key, socketChannel);
}
}
@Nullable
private ServerSocketChannel openServerSocketChannel() throws IOException {
ServerSocketChannel result = null;
try {
result = ServerSocketChannel.open();
} finally {
if (result != null)
closeables.add(result);
}
return result;
}
/**
* sets interestOps to "selector keys",The change to interestOps much be on the same thread as
* the selector. This class, allows via {@link AbstractChannelReplicator
* .KeyInterestUpdater#set(int)} to holds a pending change in interestOps ( via a bitset ),
* this change is processed later on the same thread as the selector
*/
private static class KeyInterestUpdater {
@NotNull
private final DirectBitSet changeOfOpWriteRequired;
@NotNull
private final SelectionKey[] selectionKeys;
private final int op;
KeyInterestUpdater(int op, @NotNull final SelectionKey[] selectionKeys) {
this.op = op;
this.selectionKeys = selectionKeys;
long bitSetSize = LONGS.align(BYTES.alignAndConvert(selectionKeys.length, BITS), BYTES);
changeOfOpWriteRequired = new ATSDirectBitSet(DirectStore.allocate(bitSetSize).bytes());
}
public void applyUpdates() {
for (long i = changeOfOpWriteRequired.clearNextSetBit(0L); i >= 0;
i = changeOfOpWriteRequired.clearNextSetBit(i + 1)) {
final SelectionKey key = selectionKeys[((int) i)];
try {
key.interestOps(key.interestOps() | op);
} catch (Exception e) {
LOG.debug("", e);
}
}
}
/**
* @param keyIndex the index of the key that has changed, the list of keys is provided by
* the constructor {@link KeyInterestUpdater(int, SelectionKey[])}
*/
public void set(int keyIndex) {
changeOfOpWriteRequired.setIfClear(keyIndex);
}
}
private class ServerConnector extends AbstractConnector {
@NotNull
private final Details details;
private ServerConnector(@NotNull Details details) {
super("TCP-ServerConnector-" + localIdentifier);
this.details = details;
}
@NotNull
@Override
public String toString() {
return "ServerConnector{" +
"" + details +
'}';
}
@Nullable
SelectableChannel doConnect() throws
IOException, InterruptedException {
final ServerSocketChannel serverChannel = openServerSocketChannel();
if (serverChannel == null)
return null;
serverChannel.socket().setReceiveBufferSize(BUFFER_SIZE);
serverChannel.configureBlocking(false);
serverChannel.register(TcpReplicator.this.selector, 0);
ServerSocket serverSocket = null;
try {
serverSocket = serverChannel.socket();
} finally {
if (serverSocket != null)
closeables.add(serverSocket);
}
if (serverSocket == null)
return null;
serverSocket.setReuseAddress(true);
serverSocket.bind(details.address());
// these can be run on this thread
addPendingRegistration(() -> {
final Attached attached = new Attached();
attached.connector = ServerConnector.this;
try {
serverChannel.register(TcpReplicator.this.selector, OP_ACCEPT, attached);
} catch (ClosedChannelException e) {
LOG.debug("", e);
}
});
selector.wakeup();
return serverChannel;
}
}
private class ClientConnector extends AbstractConnector {
@NotNull
private final Details details;
private ClientConnector(@NotNull Details details) {
super("TCP-ClientConnector-" + details.localIdentifier());
this.details = details;
}
@NotNull
@Override
public String toString() {
return "ClientConnector{" + details + '}';
}
/**
* blocks until connected
*/
@Override
SelectableChannel doConnect() throws IOException, InterruptedException {
boolean success = false;
final SocketChannel socketChannel = openSocketChannel(TcpReplicator.this.closeables);
try {
socketChannel.configureBlocking(false);
socketChannel.socket().setReuseAddress(true);
socketChannel.socket().setSoLinger(false, 0);
socketChannel.socket().setSoTimeout(0);
socketChannel.connect(details.address());
// Under experiment, the concoction was found to be more successful if we
// paused before registering the OP_CONNECT
Thread.sleep(10);
// the registration has be be run on the same thread as the selector
addPendingRegistration(new Runnable() {
@Override
public void run() {
final Attached attached = new Attached();
attached.connector = ClientConnector.this;
try {
socketChannel.register(selector, OP_CONNECT, attached);
} catch (ClosedChannelException e) {
if (socketChannel.isOpen())
LOG.error("", e);
}
}
});
selector.wakeup();
success = true;
return socketChannel;
} finally {
if (!success) {
try {
try {
socketChannel.socket().close();
} catch (Exception e) {
LOG.error("", e);
}
socketChannel.close();
} catch (IOException e) {
LOG.error("", e);
}
this.connectLater();
}
}
}
}
/**
* Attached to the NIO selection key via methods such as {@link SelectionKey#attach(Object)}
*/
class Attached implements Replica.ModificationNotifier {
public TcpSocketChannelEntryReader entryReader;
public TcpSocketChannelEntryWriter entryWriter;
@Nullable
public Replica.ModificationIterator remoteModificationIterator;
// used for connect later
public AbstractConnector connector;
public long remoteBootstrapTimestamp = Long.MIN_VALUE;
public byte remoteIdentifier = Byte.MIN_VALUE;
public boolean hasRemoteHeartbeatInterval;
// true if its socket is a ServerSocket
public boolean isServer;
public boolean handShakingComplete;
public String serverVersion;
public long remoteHeartbeatInterval = heartBeatIntervalMillis;
boolean isHandShakingComplete() {
return handShakingComplete;
}
/**
* called whenever there is a change to the modification iterator
*/
@Override
public void onChange() {
if (remoteIdentifier != Byte.MIN_VALUE)
TcpReplicator.this.opWriteUpdater.set(remoteIdentifier);
}
}
/**
* @author Rob Austin.
*/
public class TcpSocketChannelEntryWriter {
@NotNull
private final EntryCallback entryCallback;
// if uncompletedWork is set ( not null ) , this must be completed before any further work
// is carried out
@Nullable
public Work uncompletedWork;
private long lastSentTime;
private TcpSocketChannelEntryWriter() {
entryCallback = new EntryCallback(externalizable, replicationConfig.tcpBufferSize());
}
public boolean isWorkIncomplete() {
return uncompletedWork != null;
}
public void workCompleted() {
uncompletedWork = null;
}
/**
* writes the timestamp into the buffer
*
* @param localIdentifier the current nodes identifier
*/
void identifierToBuffer(final byte localIdentifier) {
in().writeByte(localIdentifier);
}
public void ensureBufferSize(long size) {
if (in().remaining() < size) {
size += entryCallback.in().position();
if (size > Integer.MAX_VALUE)
throw new UnsupportedOperationException();
entryCallback.resizeBuffer((int) size);
}
}
void resizeToMessage(@NotNull IllegalStateException e) {
String message = e.getMessage();
if (message.startsWith("java.io.IOException: Not enough available space for writing ")) {
String substring = message.substring("java.io.IOException: Not enough available space for writing ".length(), message.length());
int i = substring.indexOf(' ');
if (i != -1) {
int size = Integer.parseInt(substring.substring(0, i));
long requiresExtra = size - in().remaining();
ensureBufferSize((int) (in().capacity() + requiresExtra));
} else
throw e;
} else
throw e;
}
public Bytes in() {
return entryCallback.in();
}
private ByteBuffer out() {
return entryCallback.out();
}
/**
* sends the identity and timestamp of this node to a remote node
*
* @param timeStampOfLastMessage the last timestamp we received a message from that node
*/
void writeRemoteBootstrapTimestamp(final long timeStampOfLastMessage) {
in().writeLong(timeStampOfLastMessage);
}
void writeServerVersion() {
in().write(String.format("%1$" + 64 + "s", version()).toCharArray());
}
/**
* writes all the entries that have changed, to the buffer which will later be written to
* TCP/IP
* @param modificationIterator a record of which entries have modification
*
*/
void entriesToBuffer(@NotNull final Replica.ModificationIterator modificationIterator) {
int entriesWritten = 0;
try {
for (; ; entriesWritten++) {
long start = in().position();
boolean success = modificationIterator.nextEntry(entryCallback, 0);
// if not success this is most likely due to the next entry not fitting into
// the buffer and the buffer can not be re-sized above Integer.max_value, in
// this case success will return false, so we return so that we can send to
// the socket what we have.
if (!success)
return;
long entrySize = in().position() - start;
if (entrySize > largestEntrySoFar)
largestEntrySoFar = entrySize;
// we've filled up the buffer lets give another channel a chance to send
// some data
if (in().remaining() <= largestEntrySoFar || in().position() >
replicationConfig.tcpBufferSize())
return;
// if we have space in the buffer to write more data and we just wrote data
// into the buffer then let try and write some more
}
} finally {
if (LOG.isDebugEnabled())
LOG.debug("Entries written: {}", entriesWritten);
}
}
/**
* writes the contents of the buffer to the socket
*
* @param socketChannel the socket to publish the buffer to
* @param approxTime an approximation of the current time in millis
* @throws IOException
*/
private int writeBufferToSocket(@NotNull final SocketChannel socketChannel,
final long approxTime) throws IOException {
final Bytes in = in();
final ByteBuffer out = out();
if (in.position() == 0)
return 0;
// if we still have some unwritten writer from last time
lastSentTime = approxTime;
assert in.position() <= Integer.MAX_VALUE;
int size = (int) in.position();
out.limit(size);
final int len = socketChannel.write(out);
if (LOG.isDebugEnabled())
LOG.debug("bytes-written=" + len);
if (len == size) {
out.clear();
in.clear();
} else {
out.compact();
in.position(out.position());
in.limit(in.capacity());
out.clear();
}
return len;
}
/**
* used to send an single zero byte if we have not send any data for up to the
* localHeartbeatInterval
*/
private void writeHeartbeatToBuffer() {
// denotes the state - 0 for a heartbeat
in().writeByte(HEARTBEAT);
// denotes the size in bytes
in().writeInt(0);
}
private void writeRemoteHeartbeatInterval(long localHeartbeatInterval) {
in().writeLong(localHeartbeatInterval);
}
public boolean doWork() {
return uncompletedWork != null && uncompletedWork.doWork(in());
}
public boolean hasBytesToWrite() {
return in().position() > 0;
}
}
/**
* Reads map entries from a socket, this could be a client or server socket
*/
class TcpSocketChannelEntryReader {
public static final int HEADROOM = 1024;
public static final int SIZE_OF_BOOTSTRAP_TIMESTAMP = 8;
public long lastHeartBeatReceived = System.currentTimeMillis();
ByteBuffer in;
ByteBufferBytes out;
private long sizeInBytes;
private byte state;
private TcpSocketChannelEntryReader() {
in = ByteBuffer.allocateDirect(replicationConfig.tcpBufferSize());
out = new ByteBufferBytes(in.slice());
out.limit(0);
in.clear();
}
void resizeBuffer(long size) {
assert size < Integer.MAX_VALUE;
if (size < in.capacity())
throw new IllegalStateException("it not possible to resize the buffer smaller");
final ByteBuffer buffer = ByteBuffer.allocateDirect((int) size)
.order(ByteOrder.nativeOrder());
final int inPosition = in.position();
long outPosition = out.position();
long outLimit = out.limit();
out = new ByteBufferBytes(buffer.slice());
// TODO why copy byte by byte?!
in.position(0);
for (int i = 0; i < inPosition; i++) {
buffer.put(in.get());
}
in = buffer;
in.limit(in.capacity());
in.position(inPosition);
out.limit(outLimit);
out.position(outPosition);
}
/**
* reads from the socket and writes them to the buffer
*
* @param socketChannel the socketChannel to read from
* @return the number of bytes read
* @throws IOException
*/
private int readSocketToBuffer(@NotNull final SocketChannel socketChannel)
throws IOException {
compactBuffer();
final int len = socketChannel.read(in);
out.limit(in.position());
return len;
}
/**
* reads entries from the buffer till empty
*
* @param attached
* @param key
* @throws InterruptedException
*/
void entriesFromBuffer(@NotNull Attached attached, @NotNull SelectionKey key) {
int entriesRead = 0;
try {
for (; ; entriesRead++) {
out.limit(in.position());
// its set to MIN_VALUE when it should be read again
if (state == NOT_SET) {
if (out.remaining() < SIZE_OF_SIZE + 1)
return;
// state is used for heartbeat
state = out.readByte();
sizeInBytes = out.readInt();
assert sizeInBytes >= 0;
// if the buffer is too small to read this payload we will have to grow the
// size of the buffer
long requiredSize = sizeInBytes + SIZE_OF_SIZE + 1 +
SIZE_OF_BOOTSTRAP_TIMESTAMP;
if (out.capacity() < requiredSize) {
attached.entryReader.resizeBuffer(requiredSize + HEADROOM);
}
// means this is heartbeat
if (state == NOT_SET)
continue;
}
if (out.remaining() < sizeInBytes) {
return;
}
final long nextEntryPos = out.position() + sizeInBytes;
assert nextEntryPos > 0;
final long limit = out.limit();
out.limit(nextEntryPos);
externalizable.readExternalEntry(out);
out.limit(limit);
// skip onto the next entry
out.position(nextEntryPos);
state = NOT_SET;
sizeInBytes = 0;
}
} finally {
if (LOG.isDebugEnabled())
LOG.debug("Entries read: {}", entriesRead);
}
}
/**
* compacts the buffer and updates the {@code in} and {@code out} accordingly
*/
private void compactBuffer() {
// the maxEntrySizeBytes used here may not be the maximum size of the entry in its
// serialized form however, its only use as an indication that the buffer is becoming
// full and should be compacted the buffer can be compacted at any time
if (in.position() == 0 || in.remaining() > largestEntrySoFar)
return;
in.limit(in.position());
assert out.position() < Integer.MAX_VALUE;
in.position((int) out.position());
in.compact();
out.position(0);
}
/**
* @return the identifier or -1 if unsuccessful
*/
byte identifierFromBuffer() {
return (out.remaining() >= 1) ? out.readByte() : Byte.MIN_VALUE;
}
/**
* @return the timestamp or -1 if unsuccessful
*/
long remoteBootstrapTimestamp() {
if (out.remaining() >= 8)
return out.readLong();
else
return Long.MIN_VALUE;
}
/**
* @return the timestamp or -1 if unsuccessful
*/
String readRemoteServerVersion() {
if (out.remaining() >= 64) {
char[] chars = new char[64];
out.readFully(chars, 0, chars.length);
return new String(chars).trim();
} else
return null;
}
public long readRemoteHeartbeatIntervalFromBuffer() {
return (out.remaining() >= 8) ? out.readLong() : Long.MIN_VALUE;
}
}
}