/**
* Copyright (C) 2006-2009 Dustin Sallings
* Copyright (C) 2009-2011 Couchbase, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALING
* IN THE SOFTWARE.
*
*
* Portions Copyright (C) 2012-2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Amazon Software License (the "License"). You may not use this
* file except in compliance with the License. A copy of the License is located at
* http://aws.amazon.com/asl/
* or in the "license" file accompanying this file. This file is distributed on
* an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or
* implied. See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.spy.memcached.protocol;
import java.io.IOException;
import java.net.SocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.SocketChannel;
import java.util.ArrayList;
import java.util.Collection;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import net.spy.memcached.MemcachedNode;
import net.spy.memcached.compat.SpyObject;
import net.spy.memcached.config.NodeEndPoint;
import net.spy.memcached.ops.Operation;
import net.spy.memcached.ops.OperationState;
import net.spy.memcached.protocol.binary.TapAckOperationImpl;
/**
* Represents a node with the memcached cluster, along with buffering and
* operation queues.
*/
public abstract class TCPMemcachedNodeImpl extends SpyObject implements
MemcachedNode {
private NodeEndPoint nodeEndPoint;
private SocketAddress socketAddress;
private final ByteBuffer rbuf;
private final ByteBuffer wbuf;
protected final BlockingQueue<Operation> writeQ;
private final BlockingQueue<Operation> readQ;
private final BlockingQueue<Operation> inputQueue;
private final long opQueueMaxBlockTime;
// This has been declared volatile so it can be used as an availability
// indicator.
private volatile int reconnectAttempt = 1;
private SocketChannel channel;
private int toWrite = 0;
protected Operation optimizedOp = null;
private volatile SelectionKey sk = null;
private boolean shouldAuth = false;
private CountDownLatch authLatch;
private ArrayList<Operation> reconnectBlocked;
private long defaultOpTimeout;
// operation Future.get timeout counter
private final AtomicInteger continuousTimeout = new AtomicInteger(0);
public TCPMemcachedNodeImpl(SocketAddress sa, SocketChannel c, int bufSize,
BlockingQueue<Operation> rq, BlockingQueue<Operation> wq,
BlockingQueue<Operation> iq, long opQueueMaxBlockTime,
boolean waitForAuth, long dt) {
super();
assert sa != null : "No SocketAddress";
assert c != null : "No SocketChannel";
assert bufSize > 0 : "Invalid buffer size: " + bufSize;
assert rq != null : "No operation read queue";
assert wq != null : "No operation write queue";
assert iq != null : "No input queue";
socketAddress = sa;
setChannel(c);
// Since these buffers are allocated rarely (only on client creation
// or reconfigure), and are passed to Channel.read() and Channel.write(),
// use direct buffers to avoid
// http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6214569
rbuf = ByteBuffer.allocateDirect(bufSize);
wbuf = ByteBuffer.allocateDirect(bufSize);
getWbuf().clear();
readQ = rq;
writeQ = wq;
inputQueue = iq;
this.opQueueMaxBlockTime = opQueueMaxBlockTime;
shouldAuth = waitForAuth;
defaultOpTimeout = dt;
setupForAuth();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#copyInputQueue()
*/
public final void copyInputQueue() {
Collection<Operation> tmp = new ArrayList<Operation>();
// don't drain more than we have space to place
inputQueue.drainTo(tmp, writeQ.remainingCapacity());
writeQ.addAll(tmp);
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#destroyInputQueue()
*/
public Collection<Operation> destroyInputQueue() {
Collection<Operation> rv = new ArrayList<Operation>();
inputQueue.drainTo(rv);
return rv;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#setupResend()
*/
public final void setupResend() {
// First, reset the current write op, or cancel it if we should
// be authenticating
Operation op = getCurrentWriteOp();
if (shouldAuth && op != null) {
op.cancel();
} else if (op != null) {
ByteBuffer buf = op.getBuffer();
if (buf != null) {
buf.reset();
} else {
getLogger().info("No buffer for current write op, removing");
removeCurrentWriteOp();
}
}
// Now cancel all the pending read operations. Might be better to
// to requeue them.
while (hasReadOp()) {
op = removeCurrentReadOp();
if (op != getCurrentWriteOp()) {
getLogger().warn("Discarding partially completed op: %s", op);
op.cancel();
}
}
while (shouldAuth && hasWriteOp()) {
op = removeCurrentWriteOp();
getLogger().warn("Discarding partially completed op: %s", op);
op.cancel();
}
getWbuf().clear();
getRbuf().clear();
toWrite = 0;
}
// Prepare the pending operations. Return true if there are any pending
// ops
private boolean preparePending() {
// Copy the input queue into the write queue.
copyInputQueue();
// Now check the ops
Operation nextOp = getCurrentWriteOp();
while (nextOp != null && nextOp.isCancelled()) {
getLogger().info("Removing cancelled operation: %s", nextOp);
removeCurrentWriteOp();
nextOp = getCurrentWriteOp();
}
return nextOp != null;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#fillWriteBuffer(boolean)
*/
public final void fillWriteBuffer(boolean shouldOptimize) {
if (toWrite == 0 && readQ.remainingCapacity() > 0) {
getWbuf().clear();
Operation o=getNextWritableOp();
while(o != null && toWrite < getWbuf().capacity()) {
synchronized(o) {
assert o.getState() == OperationState.WRITING;
ByteBuffer obuf = o.getBuffer();
assert obuf != null : "Didn't get a write buffer from " + o;
int bytesToCopy = Math.min(getWbuf().remaining(), obuf.remaining());
byte[] b = new byte[bytesToCopy];
obuf.get(b);
getWbuf().put(b);
getLogger().debug("After copying stuff from %s: %s", o, getWbuf());
if (!o.getBuffer().hasRemaining()) {
o.writeComplete();
transitionWriteItem();
preparePending();
if (shouldOptimize) {
optimize();
}
o=getNextWritableOp();
}
toWrite += bytesToCopy;
}
}
getWbuf().flip();
assert toWrite <= getWbuf().capacity() : "toWrite exceeded capacity: "
+ this;
assert toWrite == getWbuf().remaining() : "Expected " + toWrite
+ " remaining, got " + getWbuf().remaining();
} else {
getLogger().debug("Buffer is full, skipping");
}
}
private Operation getNextWritableOp() {
Operation o = getCurrentWriteOp();
while (o != null && o.getState() == OperationState.WRITE_QUEUED) {
synchronized(o) {
if (o.isCancelled()) {
getLogger().debug("Not writing cancelled op.");
Operation cancelledOp = removeCurrentWriteOp();
assert o == cancelledOp;
} else if (o.isTimedOut(defaultOpTimeout)) {
getLogger().debug("Not writing timed out op.");
Operation timedOutOp = removeCurrentWriteOp();
assert o == timedOutOp;
} else {
o.writing();
if (!(o instanceof TapAckOperationImpl)) {
readQ.add(o);
}
return o;
}
o = getCurrentWriteOp();
}
}
return o;
}
/* (non-Javadoc)
* @see net.spy.memcached.MemcachedNode#transitionWriteItem()
*/
public final void transitionWriteItem() {
Operation op = removeCurrentWriteOp();
assert op != null : "There is no write item to transition";
getLogger().debug("Finished writing %s", op);
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#optimize()
*/
protected abstract void optimize();
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getCurrentReadOp()
*/
public final Operation getCurrentReadOp() {
return readQ.peek();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#removeCurrentReadOp()
*/
public final Operation removeCurrentReadOp() {
return readQ.remove();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getCurrentWriteOp()
*/
public final Operation getCurrentWriteOp() {
return optimizedOp == null ? writeQ.peek() : optimizedOp;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#removeCurrentWriteOp()
*/
public final Operation removeCurrentWriteOp() {
Operation rv = optimizedOp;
if (rv == null) {
rv = writeQ.remove();
} else {
optimizedOp = null;
}
return rv;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#hasReadOp()
*/
public final boolean hasReadOp() {
return !readQ.isEmpty();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#hasWriteOp()
*/
public final boolean hasWriteOp() {
return !(optimizedOp == null && writeQ.isEmpty());
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#addOp(net.spy.memcached.ops.Operation)
*/
public final void addOp(Operation op) {
try {
if (!authLatch.await(1, TimeUnit.SECONDS)) {
op.cancel();
getLogger().warn("Operation canceled because authentication "
+ "or reconnection and authentication has "
+ "taken more than one second to complete.");
getLogger().debug("Canceled operation %s", op.toString());
return;
}
if (!inputQueue.offer(op, opQueueMaxBlockTime, TimeUnit.MILLISECONDS)) {
throw new IllegalStateException("Timed out waiting to add " + op
+ "(max wait=" + opQueueMaxBlockTime + "ms)");
}
} catch (InterruptedException e) {
// Restore the interrupted status
Thread.currentThread().interrupt();
throw new IllegalStateException("Interrupted while waiting to add " + op);
}
}
/*
* (non-Javadoc)
*
* @see
* net.spy.memcached.MemcachedNode#insertOp(net.spy.memcached.ops.Operation)
*/
public final void insertOp(Operation op) {
ArrayList<Operation> tmp = new ArrayList<Operation>(inputQueue.size() + 1);
tmp.add(op);
inputQueue.drainTo(tmp);
inputQueue.addAll(tmp);
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getSelectionOps()
*/
public final int getSelectionOps() {
int rv = 0;
if (getChannel().isConnected()) {
if (hasReadOp()) {
rv |= SelectionKey.OP_READ;
}
if (toWrite > 0 || hasWriteOp()) {
rv |= SelectionKey.OP_WRITE;
}
} else {
rv = SelectionKey.OP_CONNECT;
}
return rv;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getRbuf()
*/
public final ByteBuffer getRbuf() {
return rbuf;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getWbuf()
*/
public final ByteBuffer getWbuf() {
return wbuf;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getSocketAddress()
*/
public final SocketAddress getSocketAddress() {
return socketAddress;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getNodeEndPoint()
*/
public final NodeEndPoint getNodeEndPoint() {
return nodeEndPoint;
}
/**
*
* @param nodeEndPoint
*/
public void setNodeEndPoint(NodeEndPoint nodeEndPoint){
this.nodeEndPoint = nodeEndPoint;
this.socketAddress = nodeEndPoint.getInetSocketAddress();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#isActive()
*/
public final boolean isActive() {
return reconnectAttempt == 0 && getChannel() != null
&& getChannel().isConnected();
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#reconnecting()
*/
public final void reconnecting() {
reconnectAttempt++;
continuousTimeout.set(0);
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#connected()
*/
public final void connected() {
reconnectAttempt = 0;
continuousTimeout.set(0);
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getReconnectCount()
*/
public final int getReconnectCount() {
return reconnectAttempt;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#toString()
*/
@Override
public final String toString() {
int sops = 0;
if (getSk() != null && getSk().isValid()) {
sops = getSk().interestOps();
}
int rsize = readQ.size() + (optimizedOp == null ? 0 : 1);
int wsize = writeQ.size();
int isize = inputQueue.size();
return "{QA sa=" + getSocketAddress() + ", #Rops=" + rsize
+ ", #Wops=" + wsize
+ ", #iq=" + isize
+ ", topRop=" + getCurrentReadOp()
+ ", topWop=" + getCurrentWriteOp()
+ ", toWrite=" + toWrite
+ ", interested=" + sops + "}";
}
/*
* (non-Javadoc)
*
* @see
* net.spy.memcached.MemcachedNode#registerChannel
* (java.nio.channels.SocketChannel, java.nio.channels.SelectionKey)
*/
public final void registerChannel(SocketChannel ch, SelectionKey skey) {
setChannel(ch);
setSk(skey);
}
/*
* (non-Javadoc)
*
* @see
* net.spy.memcached.MemcachedNode#setChannel(java.nio.channels.SocketChannel)
*/
public final void setChannel(SocketChannel to) {
assert channel == null || !channel.isOpen()
: "Attempting to overwrite channel";
channel = to;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getChannel()
*/
public final SocketChannel getChannel() {
return channel;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#setSk(java.nio.channels.SelectionKey)
*/
public final void setSk(SelectionKey to) {
sk = to;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getSk()
*/
public final SelectionKey getSk() {
return sk;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getBytesRemainingInBuffer()
*/
public final int getBytesRemainingToWrite() {
return toWrite;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#writeSome()
*/
public final int writeSome() throws IOException {
int wrote = channel.write(wbuf);
assert wrote >= 0 : "Wrote negative bytes?";
toWrite -= wrote;
assert toWrite >= 0 : "toWrite went negative after writing " + wrote
+ " bytes for " + this;
getLogger().debug("Wrote %d bytes", wrote);
return wrote;
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#setContinuousTimeout
*/
public void setContinuousTimeout(boolean timedOut) {
if (timedOut && isActive()) {
continuousTimeout.incrementAndGet();
} else {
continuousTimeout.set(0);
}
}
/*
* (non-Javadoc)
*
* @see net.spy.memcached.MemcachedNode#getContinuousTimeout
*/
public int getContinuousTimeout() {
return continuousTimeout.get();
}
public final void fixupOps() {
// As the selection key can be changed at any point due to node
// failure, we'll grab the current volatile value and configure it.
SelectionKey s = sk;
if (s != null && s.isValid()) {
int iops = getSelectionOps();
getLogger().debug("Setting interested opts to %d", iops);
s.interestOps(iops);
} else {
getLogger().debug("Selection key is not valid.");
}
}
public final void authComplete() {
if (reconnectBlocked != null && reconnectBlocked.size() > 0) {
inputQueue.addAll(reconnectBlocked);
}
authLatch.countDown();
}
public final void setupForAuth() {
if (shouldAuth) {
authLatch = new CountDownLatch(1);
if (inputQueue.size() > 0) {
reconnectBlocked = new ArrayList<Operation>(inputQueue.size() + 1);
inputQueue.drainTo(reconnectBlocked);
}
assert (inputQueue.size() == 0);
setupResend();
} else {
authLatch = new CountDownLatch(0);
}
}
}