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Client library for working with the NATS messaging system.
/*
* Copyright (c) 2015-2016 Apcera Inc. All rights reserved. This program and the accompanying
* materials are made available under the terms of the MIT License (MIT) which accompanies this
* distribution, and is available at http://opensource.org/licenses/MIT
*/
package io.nats.client;
import static io.nats.client.Nats.ConnState;
import static io.nats.client.Nats.ConnState.CLOSED;
import static io.nats.client.Nats.ConnState.CONNECTED;
import static io.nats.client.Nats.ConnState.CONNECTING;
import static io.nats.client.Nats.ConnState.DISCONNECTED;
import static io.nats.client.Nats.ConnState.RECONNECTING;
import static io.nats.client.Nats.ERR_BAD_SUBJECT;
import static io.nats.client.Nats.ERR_BAD_SUBSCRIPTION;
import static io.nats.client.Nats.ERR_BAD_TIMEOUT;
import static io.nats.client.Nats.ERR_CONNECTION_CLOSED;
import static io.nats.client.Nats.ERR_CONNECTION_READ;
import static io.nats.client.Nats.ERR_MAX_PAYLOAD;
import static io.nats.client.Nats.ERR_NO_INFO_RECEIVED;
import static io.nats.client.Nats.ERR_NO_SERVERS;
import static io.nats.client.Nats.ERR_RECONNECT_BUF_EXCEEDED;
import static io.nats.client.Nats.ERR_SECURE_CONN_REQUIRED;
import static io.nats.client.Nats.ERR_SECURE_CONN_WANTED;
import static io.nats.client.Nats.ERR_SLOW_CONSUMER;
import static io.nats.client.Nats.ERR_STALE_CONNECTION;
import static io.nats.client.Nats.ERR_TCP_FLUSH_FAILED;
import static io.nats.client.Nats.ERR_TIMEOUT;
import static io.nats.client.Nats.PERMISSIONS_ERR;
import static io.nats.client.Nats.TLS_SCHEME;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.annotations.SerializedName;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.nio.BufferOverflowException;
import java.nio.ByteBuffer;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Random;
import java.util.TimerTask;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class ConnectionImpl implements Connection {
private final Logger logger = LoggerFactory.getLogger(ConnectionImpl.class);
private String version = null;
private static final String INBOX_PREFIX = "_INBOX.";
private ConnState status = DISCONNECTED;
protected static final String STALE_CONNECTION = "Stale Connection";
// Default language string for CONNECT message
protected static final String LANG_STRING = "java";
// The size of the read buffer in readLoop.
protected static final int DEFAULT_BUF_SIZE = 65536;
// The size of the BufferedInputStream and BufferedOutputStream on top of the socket.
protected static final int DEFAULT_STREAM_BUF_SIZE = 65536;
// The buffered size of the flush "kick" channel
protected static final int FLUSH_CHAN_SIZE = 1;
// The number of msec the flusher will wait between flushes
private long flushTimerInterval = 1;
private TimeUnit flushTimerUnit = TimeUnit.MICROSECONDS;
protected static final String CRLF = "\r\n";
protected static final String _EMPTY_ = "";
protected static final String _SPC_ = " ";
protected static final String _PUB_P_ = "PUB ";
// Operations
protected static final String _OK_OP_ = "+OK";
protected static final String _ERR_OP_ = "-ERR";
protected static final String _MSG_OP_ = "MSG";
protected static final String _PING_OP_ = "PING";
protected static final String _PONG_OP_ = "PONG";
protected static final String _INFO_OP_ = "INFO";
// Message Prototypes
protected static final String CONN_PROTO = "CONNECT %s" + CRLF;
protected static final String PING_PROTO = "PING" + CRLF;
protected static final String PONG_PROTO = "PONG" + CRLF;
protected static final String PUB_PROTO = "PUB %s %s %d" + CRLF;
protected static final String SUB_PROTO = "SUB %s%s %d" + CRLF;
protected static final String UNSUB_PROTO = "UNSUB %d %s" + CRLF;
protected static final String OK_PROTO = _OK_OP_ + CRLF;
enum ClientProto {
CLIENT_PROTO_ZERO(0), // CLIENT_PROTO_ZERO is the original client protocol from 2009.
CLIENT_PROTO_INFO(1); // clientProtoInfo signals a client can receive more then the original
// INFO block. This can be used to update clients on other cluster
// members, etc.
private final int value;
ClientProto(int value) {
this.value = value;
}
public int getValue() {
return value;
}
}
private ConnectionImpl nc = null;
final Lock mu = new ReentrantLock();
// protected final Lock mu = new AlternateDeadlockDetectingLock(true, true);
private final AtomicLong sidCounter = new AtomicLong(0L);
private URI url = null;
private Options opts = null;
private TcpConnectionFactory tcf = null;
private TcpConnection conn = null;
// Prepare protocol messages for efficiency
private ByteBuffer pubProtoBuf = null;
// we have a buffered reader for writing, and reading.
// This is for both performance, and having to work around
// interlinked read/writes (supported by the underlying network
// stream, but not the BufferedStream).
private OutputStream bw = null;
private InputStream br = null;
private ByteArrayOutputStream pending = null;
private Map subs = new ConcurrentHashMap();
private List srvPool = null;
private Map urls = null;
private Exception lastEx = null;
private ServerInfo info = null;
private int pout;
private Parser parser = new Parser(this);
private static final byte[] pingProtoBytes = PING_PROTO.getBytes();
private static final int pingProtoBytesLen = pingProtoBytes.length;
private static final byte[] pongProtoBytes = PONG_PROTO.getBytes();
private static final int pongProtoBytesLen = pongProtoBytes.length;
private static final byte[] pubPrimBytes = _PUB_P_.getBytes();
private static final int pubPrimBytesLen = pubPrimBytes.length;
private static final byte[] crlfProtoBytes = CRLF.getBytes();
private static final int crlfProtoBytesLen = crlfProtoBytes.length;
private Statistics stats = null;
private List> pongs;
private static final int NUM_CORE_THREADS = 4;
// The main executor service for core threads and timers
private ScheduledExecutorService exec;
static final String EXEC_NAME = "jnats-exec";
// Executor for subscription threads
private ExecutorService subexec;
static final String SUB_EXEC_NAME = "jnats-subscriptions";
// Executor for async connection callbacks
private ExecutorService cbexec;
static final String CB_EXEC_NAME = "jnats-callbacks";
// The ping timer task
private ScheduledFuture ptmr = null;
static final String PINGTIMER = "pingtimer";
static final String READLOOP = "readloop";
static final String FLUSHER = "flusher";
private final Map> tasks = new HashMap<>();
private static final int NUM_WATCHER_THREADS = 2;
private CountDownLatch socketWatchersStartLatch = new CountDownLatch(NUM_WATCHER_THREADS);
private CountDownLatch socketWatchersDoneLatch = null;
// The flusher signalling channel
private BlockingQueue fch;
// ConnectionImpl() {
// }
ConnectionImpl(Options opts) {
Properties props = this.getProperties(Nats.PROP_PROPERTIES_FILENAME);
version = props.getProperty(Nats.PROP_CLIENT_VERSION);
this.nc = this;
this.opts = opts;
this.stats = new Statistics();
if (opts.getFactory() != null) {
tcf = opts.getFactory();
} else {
tcf = new TcpConnectionFactory();
}
}
ScheduledExecutorService createScheduler() {
ScheduledThreadPoolExecutor sexec = (ScheduledThreadPoolExecutor)
Executors.newScheduledThreadPool(NUM_CORE_THREADS,
new NatsThreadFactory(EXEC_NAME));
sexec.setRemoveOnCancelPolicy(true);
return sexec;
}
ExecutorService createSubscriptionScheduler() {
return Executors.newCachedThreadPool(new NatsThreadFactory(SUB_EXEC_NAME));
}
ExecutorService createCallbackScheduler() {
return Executors.newSingleThreadExecutor(new NatsThreadFactory(CB_EXEC_NAME));
}
void setup() {
exec = createScheduler();
cbexec = createCallbackScheduler();
subexec = createSubscriptionScheduler();
fch = createFlushChannel();
pongs = createPongs();
subs.clear();
// predefine the start of the publish protocol message.
buildPublishProtocolBuffer(Parser.MAX_CONTROL_LINE_SIZE);
}
Properties getProperties(InputStream inputStream) {
Properties rv = new Properties();
try {
if (inputStream == null) {
rv = null;
} else {
rv.load(inputStream);
}
} catch (IOException e) {
logger.warn("nats: error loading properties from InputStream", e);
rv = null;
}
return rv;
}
Properties getProperties(String resourceName) {
InputStream is = getClass().getClassLoader().getResourceAsStream(resourceName);
return getProperties(is);
}
private void buildPublishProtocolBuffer(int size) {
pubProtoBuf = ByteBuffer.allocate(size);
pubProtoBuf.put(pubPrimBytes, 0, pubPrimBytesLen);
pubProtoBuf.mark();
}
/*
* Create the server pool using the options given. We will place a Url option first, followed by
* any Srv Options. We will randomize the server pool (except Url) unless the NoRandomize flag
* is set.
*/
void setupServerPool() {
final URI url;
if (opts.getUrl() != null) {
url = URI.create(opts.getUrl());
} else {
url = null;
}
List servers = opts.getServers();
srvPool = new ArrayList();
urls = new ConcurrentHashMap();
if (servers != null) {
for (URI s : servers) {
addUrlToPool(s, false);
}
}
if (!opts.isNoRandomize()) {
// Randomize the order
Collections.shuffle(srvPool, new Random(System.nanoTime()));
}
/*
* Insert the supplied url, if not null or empty, at the beginning of the list. Normally, if
* this is set, then opts.servers should NOT be set, and vice versa. However, we always
* allowed both to be set before, so we'll continue to do so.
*/
if (url != null) {
srvPool.add(0, new Srv(url, false));
urls.put(url.getAuthority(), url);
}
// If the pool is empty, add the default URL
if (srvPool.isEmpty()) {
addUrlToPool(Nats.DEFAULT_URL, false);
}
/*
* At this point, srvPool being empty would be programmer error.
*/
// Return the first server in the list
this.setUrl(srvPool.get(0).url);
}
/* Add a string URL to the server pool */
void addUrlToPool(String srvUrl, boolean implicit) {
URI uri = URI.create(srvUrl);
srvPool.add(new Srv(uri, implicit));
urls.put(uri.getAuthority(), uri);
}
/* Add a URL to the server pool */
void addUrlToPool(URI uri, boolean implicit) {
srvPool.add(new Srv(uri, implicit));
urls.put(uri.getAuthority(), uri);
}
Srv currentServer() {
Srv rv = null;
for (Srv s : srvPool) {
if (s.url.equals(this.getUrl())) {
rv = s;
break;
}
}
return rv;
}
Srv selectNextServer() throws IOException {
Srv srv = currentServer();
if (srv == null) {
throw new IOException(ERR_NO_SERVERS);
}
/*
* Pop the current server and put onto the end of the list. Select head of list as long as
* number of reconnect attempts under MaxReconnect.
*/
srvPool.remove(srv);
/*
* if the maxReconnect is unlimited, or the number of reconnect attempts is less than
* maxReconnect, move the current server to the end of the list.
*
*/
int maxReconnect = opts.getMaxReconnect();
if ((maxReconnect < 0) || (srv.reconnects < maxReconnect)) {
srvPool.add(srv);
}
if (srvPool.isEmpty()) {
this.setUrl(null);
throw new IOException(ERR_NO_SERVERS);
}
return srvPool.get(0);
}
Connection connect() throws IOException {
// Create actual socket connection
// For first connect we walk all servers in the pool and try
// to connect immediately.
IOException returnedErr = null;
setupServerPool();
mu.lock();
try {
for (Srv srv : srvPool) {
this.setUrl(srv.url);
try {
logger.debug("Connecting to {}", this.getUrl());
createConn();
logger.debug("Connected to {}", this.getUrl());
this.setup();
try {
processConnectInit();
srv.reconnects = 0;
returnedErr = null;
break;
} catch (IOException e) {
returnedErr = e;
mu.unlock();
close(DISCONNECTED, false);
mu.lock();
this.setUrl(null);
} catch (InterruptedException e) {
returnedErr = new IOException(e);
mu.unlock();
close(DISCONNECTED, false);
mu.lock();
this.setUrl(null);
}
} catch (IOException e) { // createConn failed
// Cancel out default connection refused, will trigger the
// No servers error conditional
if (e.getMessage() != null && e.getMessage().contains("Connection refused")) {
setLastError(null);
}
}
} // for
if ((returnedErr == null) && (this.status != CONNECTED)) {
returnedErr = new IOException(ERR_NO_SERVERS);
}
if (returnedErr != null) {
throw (returnedErr);
}
cbexec = createCallbackScheduler();
return this;
} finally {
mu.unlock();
}
}
/*
* createConn will connect to the server and wrap the appropriate bufio structures. A new
* connection is always created.
*/
void createConn() throws IOException {
if (opts.getConnectionTimeout() < 0) {
logger.warn("{}: {}", ERR_BAD_TIMEOUT, opts.getConnectionTimeout());
throw new IOException(ERR_BAD_TIMEOUT);
}
Srv srv = currentServer();
if (srv == null) {
throw new IOException(ERR_NO_SERVERS);
} else {
srv.updateLastAttempt();
}
try {
logger.debug("Opening {}", srv.url);
conn = tcf.createConnection();
conn.open(srv.url.toString(), opts.getConnectionTimeout());
logger.trace("Opened {} as TcpConnection ({})", srv.url, conn);
} catch (IOException e) {
logger.debug("Couldn't establish connection to {}: {}", srv.url, e.getMessage());
throw (e);
}
if ((pending != null) && (bw != null)) {
try {
bw.flush();
} catch (IOException e) {
logger.warn(ERR_TCP_FLUSH_FAILED);
}
}
bw = conn.getOutputStream(DEFAULT_STREAM_BUF_SIZE);
br = conn.getInputStream(DEFAULT_STREAM_BUF_SIZE);
}
BlockingQueue createMsgChannel() {
return createMsgChannel(Integer.MAX_VALUE);
}
BlockingQueue createMsgChannel(int size) {
int theSize = size;
if (theSize <= 0) {
theSize = 1;
}
return new LinkedBlockingQueue(theSize);
}
BlockingQueue createBooleanChannel() {
return new LinkedBlockingQueue();
}
BlockingQueue createBooleanChannel(int size) {
int theSize = size;
if (theSize <= 0) {
theSize = 1;
}
return new LinkedBlockingQueue(theSize);
}
BlockingQueue createFlushChannel() {
return new LinkedBlockingQueue(FLUSH_CHAN_SIZE);
// return new SynchronousQueue();
}
// This will clear any pending flush calls and release pending calls.
// Lock is assumed to be held by the caller.
void clearPendingFlushCalls() {
// Clear any queued pongs, e.g. pending flush calls.
if (pongs == null) {
return;
}
for (BlockingQueue ch : pongs) {
if (ch != null) {
ch.clear();
// Signal other waiting threads that we're done
ch.add(false);
}
}
pongs.clear();
pongs = null;
}
@Override
public void close() {
close(CLOSED, true);
}
/*
* Low level close call that will do correct cleanup and set desired status. Also controls
* whether user defined callbacks will be triggered. The lock should not be held entering this
* method. This method will handle the locking manually.
*/
private void close(ConnState closeState, boolean doCBs) {
logger.debug("close({}, {})", closeState, String.valueOf(doCBs));
final ConnectionImpl nc = this;
mu.lock();
try {
if (closed()) {
this.status = closeState;
return;
}
this.status = CLOSED;
// Kick the Flusher routine so it falls out.
kickFlusher();
} finally {
mu.unlock();
}
mu.lock();
try {
// Clear any queued pongs, e.g. pending flush calls.
clearPendingFlushCalls();
// Go ahead and make sure we have flushed the outbound
if (conn != null) {
try {
if (bw != null) {
bw.flush();
}
} catch (IOException e) {
/* NOOP */
}
}
// Close sync subscribers and release any pending nextMsg() calls.
for (Map.Entry entry : subs.entrySet()) {
SubscriptionImpl sub = entry.getValue();
// for (Long key : subs.keySet()) {
// SubscriptionImpl sub = subs.get(key);
sub.lock();
try {
sub.closeChannel();
// Mark as invalid, for signaling to deliverMsgs
sub.closed = true;
// Mark connection closed in subscription
sub.connClosed = true;
// Terminate thread exec
sub.close();
} finally {
sub.unlock();
}
}
subs.clear();
// perform appropriate callback if needed for a disconnect;
if (doCBs) {
if (opts.getDisconnectedCallback() != null && conn != null) {
cbexec.submit(new Runnable() {
@Override
public void run() {
opts.getDisconnectedCallback().onDisconnect(new ConnectionEvent(nc));
logger.trace("executed DisconnectedCB");
}
});
}
if (opts.getClosedCallback() != null) {
cbexec.submit(new Runnable() {
@Override
public void run() {
opts.getClosedCallback().onClose(new ConnectionEvent(nc));
logger.trace("executed ClosedCB");
}
});
}
if (cbexec != null) {
cbexec.shutdown();
}
}
this.status = closeState;
if (conn != null) {
conn.close();
}
if (exec != null) {
shutdownAndAwaitTermination(exec, EXEC_NAME);
}
if (subexec != null) {
shutdownAndAwaitTermination(subexec, SUB_EXEC_NAME);
}
} finally {
mu.unlock();
}
}
void shutdownAndAwaitTermination(ExecutorService pool, String name) {
try {
pool.shutdownNow();
if (!pool.awaitTermination(10, TimeUnit.SECONDS)) {
logger.error("{} did not terminate", name);
}
} catch (InterruptedException ie) {
// (Re-)Cancel if current thread also interrupted
pool.shutdownNow();
// Preserve interrupt status
Thread.currentThread().interrupt();
}
}
void processConnectInit() throws IOException, InterruptedException {
// Set our status to connecting.
status = CONNECTING;
// Process the INFO protocol that we should be receiving
processExpectedInfo();
// Send the CONNECT and PING protocol, and wait for the PONG.
sendConnect();
// Reset the number of PINGs sent out
this.setActualPingsOutstanding(0);
// Start the readLoop and flusher threads
spinUpSocketWatchers();
}
// This will check to see if the connection should be
// secure. This can be dictated from either end and should
// only be called after the INIT protocol has been received.
void checkForSecure() throws IOException {
// Check to see if we need to engage TLS
// Check for mismatch in setups
if (opts.isSecure() && !info.isTlsRequired()) {
throw new IOException(ERR_SECURE_CONN_WANTED);
} else if (info.isTlsRequired() && !opts.isSecure()) {
throw new IOException(ERR_SECURE_CONN_REQUIRED);
}
// Need to rewrap with bufio
if (opts.isSecure() || TLS_SCHEME.equals(this.getUrl().getScheme())) {
makeTlsConn();
}
}
// makeSecureConn will wrap an existing Conn using TLS
void makeTlsConn() throws IOException {
conn.setTlsDebug(opts.isTlsDebug());
conn.makeTls(opts.getSslContext());
bw = conn.getOutputStream(DEFAULT_STREAM_BUF_SIZE);
br = conn.getInputStream(DEFAULT_STREAM_BUF_SIZE);
}
void processExpectedInfo() throws IOException, InterruptedException {
Control control;
try {
// Read the protocol
control = readOp();
} catch (IOException e) {
processOpError(e);
return;
}
// The nats protocol should send INFO first always.
if (!control.op.equals(_INFO_OP_)) {
throw new IOException(ERR_NO_INFO_RECEIVED);
}
// Parse the protocol
processInfo(control.args);
checkForSecure();
}
// processPing will send an immediate pong protocol response to the
// server. The server uses this mechanism to detect dead clients.
void processPing() {
try {
sendProto(pongProtoBytes, pongProtoBytesLen);
} catch (IOException e) {
setLastError(e);
// e.printStackTrace();
}
}
// processPong is used to process responses to the client's ping
// messages. We use pings for the flush mechanism as well.
void processPong() throws InterruptedException {
BlockingQueue ch = null;
mu.lockInterruptibly();
try {
if (pongs != null && pongs.size() > 0) {
ch = pongs.get(0);
pongs.remove(0);
}
setActualPingsOutstanding(0);
} finally {
mu.unlock();
}
if (ch != null) {
ch.add(true);
}
}
// processOK is a placeholder for processing OK messages.
void processOk() {
// NOOP;
}
// processInfo is used to parse the info messages sent
// from the server.
void processInfo(String infoString) {
if ((infoString == null) || infoString.isEmpty()) {
return;
}
setConnectedServerInfo(ServerInfo.createFromWire(infoString));
boolean updated = false;
if (info.getConnectUrls() != null) {
for (String s : info.getConnectUrls()) {
if (!urls.containsKey(s)) {
this.addUrlToPool(String.format("nats://%s", s), true);
updated = true;
}
}
if (updated && !opts.isNoRandomize()) {
Collections.shuffle(srvPool);
}
}
}
// processAsyncInfo does the same as processInfo, but is called
// from the parser. Calls processInfo under connection's lock
// protection.
void processAsyncInfo(byte[] asyncInfo, int offset, int length) {
mu.lock();
try {
String theInfo = new String(asyncInfo, offset, length);
// Ignore errors, we will simply not update the server pool...
processInfo(theInfo);
} finally {
mu.unlock();
}
}
// processOpError handles errors from reading or parsing the protocol.
// This is where disconnect/reconnect is initially handled.
// The lock should not be held entering this function.
void processOpError(Exception err) throws InterruptedException {
mu.lockInterruptibly();
try {
if (connecting() || closed() || reconnecting()) {
return;
}
logger.debug("Connection terminated: {}", err.getMessage());
if (opts.isReconnectAllowed() && status == CONNECTED) {
// Set our new status
status = RECONNECTING;
if (ptmr != null) {
ptmr.cancel(true);
tasks.remove(ptmr);
}
if (this.conn != null) {
try {
bw.flush();
} catch (IOException e1) {
logger.warn("I/O error during flush");
}
conn.close();
}
if (fch != null && !fch.offer(false)) {
logger.debug("Coudn't shut down flusher following connection error");
}
// Create a new pending buffer to underpin the buffered output
// stream while we are reconnecting.
setPending(new ByteArrayOutputStream(opts.getReconnectBufSize()));
setOutputStream(getPending());
if (exec.isShutdown()) {
exec = createScheduler();
}
exec.submit(new Runnable() {
public void run() {
Thread.currentThread().setName("reconnect");
try {
doReconnect();
} catch (InterruptedException e) {
logger.warn("nats: interrupted while reonnecting");
}
}
});
if (cbexec.isShutdown()) {
cbexec = createCallbackScheduler();
}
} else {
processDisconnect();
setLastError(err);
close();
}
} finally {
mu.unlock();
}
}
protected void processDisconnect() {
logger.debug("processDisconnect()");
status = DISCONNECTED;
}
@Override
public boolean isReconnecting() {
mu.lock();
try {
return reconnecting();
} finally {
mu.unlock();
}
}
boolean reconnecting() {
return (status == RECONNECTING);
}
@Override
public boolean isConnected() {
mu.lock();
try {
return connected();
} finally {
mu.unlock();
}
}
boolean connected() {
return (status == CONNECTED);
}
@Override
public boolean isClosed() {
mu.lock();
try {
return closed();
} finally {
mu.unlock();
}
}
boolean closed() {
return (status == CLOSED);
}
// flushReconnectPending will push the pending items that were
// gathered while we were in a RECONNECTING state to the socket.
void flushReconnectPendingItems() {
if (pending == null) {
return;
}
if (pending.size() > 0) {
try {
bw.write(pending.toByteArray(), 0, pending.size());
bw.flush();
} catch (IOException e) {
logger.error("Error flushing pending items", e);
}
}
pending = null;
}
// Try to reconnect using the option parameters.
// This function assumes we are allowed to reconnect.
void doReconnect() throws InterruptedException {
logger.trace("doReconnect()");
// We want to make sure we have the other watchers shutdown properly
// here before we proceed past this point
waitForExits();
logger.trace("Old threads have exited, proceeding with reconnect");
// FIXME(dlc) - We have an issue here if we have
// outstanding flush points (pongs) and they were not
// sent out, but are still in the pipe.
// Hold the lock manually and release where needed below.
mu.lockInterruptibly();
try {
// Clear any queued pongs, e.g. pending flush calls.
nc.clearPendingFlushCalls();
// Clear any errors.
setLastError(null);
// Perform appropriate callback if needed for a disconnect
if (opts.getDisconnectedCallback() != null) {
logger.trace("Spawning disconnectCB from doReconnect()");
cbexec.submit(new Runnable() {
public void run() {
opts.getDisconnectedCallback().onDisconnect(new ConnectionEvent(nc));
}
});
logger.trace("Spawned disconnectCB from doReconnect()");
}
while (!srvPool.isEmpty()) {
Srv cur;
try {
cur = selectNextServer();
this.setUrl(cur.url);
} catch (IOException nse) {
setLastError(nse);
break;
}
long sleepTime = 0L;
// Sleep appropriate amount of time before the
// connection attempt if connecting to same server
// we just got disconnected from.
long timeSinceLastAttempt = cur.timeSinceLastAttempt();
if (timeSinceLastAttempt < opts.getReconnectWait()) {
sleepTime = opts.getReconnectWait() - timeSinceLastAttempt;
}
if (sleepTime > 0) {
mu.unlock();
Thread.sleep(sleepTime);
mu.lockInterruptibly();
}
// Check if we have been closed first.
if (isClosed()) {
logger.debug("Connection has been closed while in doReconnect()");
break;
}
// Mark that we tried a reconnect
cur.reconnects++;
// try to create a new connection
try {
// conn.teardown();
createConn();
} catch (Exception e) {
// conn.teardown();
logger.trace("doReconnect: createConn() failed for {}", cur);
logger.trace("createConn failed", e);
// not yet connected, retry and hold
// the lock.
setLastError(null);
continue;
}
// We are reconnected.
stats.incrementReconnects();
// Process connect logic
try {
processConnectInit();
} catch (IOException e) {
// conn.teardown();
logger.warn("couldn't connect to {} ({})", cur.url, e.getMessage());
setLastError(e);
status = RECONNECTING;
continue;
}
logger.trace("Successful reconnect; Resetting reconnects for {}", cur);
// Clear out server stats for the server we connected to..
// cur.didConnect = true;
cur.reconnects = 0;
// Send existing subscription state
resendSubscriptions();
// Now send off and clear pending buffer
flushReconnectPendingItems();
// Flush the buffer
try {
getOutputStream().flush();
} catch (IOException e) {
logger.warn("Error flushing output stream");
setLastError(e);
status = RECONNECTING;
continue;
}
// Done with the pending buffer
setPending(null);
// This is where we are truly connected.
status = CONNECTED;
// Queue up the reconnect callback.
if (opts.getReconnectedCallback() != null) {
logger.trace("Scheduling reconnectedCb from doReconnect()");
cbexec.submit(new Runnable() {
public void run() {
opts.getReconnectedCallback().onReconnect(new ConnectionEvent(nc));
}
});
logger.trace("Scheduled reconnectedCb from doReconnect()");
}
// Release the lock here, we will return below
mu.unlock();
try {
// Make sure to flush everything
flush();
} catch (IOException e) {
if (status == CONNECTED) {
logger.warn("Error flushing connection", e);
}
}
return;
} // while
logger.trace("Reconnect FAILED");
// Call into close.. We have no servers left.
if (getLastException() == null) {
setLastError(new IOException(ERR_NO_SERVERS));
}
} finally {
mu.unlock();
}
close();
}
boolean connecting() {
return (status == CONNECTING);
}
ConnState status() {
return status;
}
static String normalizeErr(String error) {
String str = error;
if (str != null) {
str = str.replaceFirst(_ERR_OP_ + "\\s+", "").toLowerCase();
str = str.replaceAll("^\'|\'$", "");
}
return str;
}
static String normalizeErr(ByteBuffer error) {
String str = Parser.bufToString(error);
if (str != null) {
str = str.trim();
}
return normalizeErr(str);
}
// processErr processes any error messages from the server and
// sets the connection's lastError.
void processErr(ByteBuffer error) throws InterruptedException {
// boolean doCBs = false;
NATSException ex;
String err = normalizeErr(error);
if (STALE_CONNECTION.equalsIgnoreCase(err)) {
processOpError(new IOException(ERR_STALE_CONNECTION));
} else if (err.startsWith(PERMISSIONS_ERR)) {
processPermissionsViolation(err);
} else {
ex = new NATSException("nats: " + err);
ex.setConnection(this);
mu.lock();
try {
setLastError(ex);
} finally {
mu.unlock();
}
close();
}
}
// caller must lock
protected void sendConnect() throws IOException {
String line;
// Send CONNECT
bw.write(connectProto().getBytes());
bw.flush();
// Process +OK
if (opts.isVerbose()) {
line = readLine();
if (!_OK_OP_.equals(line)) {
throw new IOException(
String.format("nats: expected '%s', got '%s'", _OK_OP_, line));
}
}
// Send PING
bw.write(pingProtoBytes, 0, pingProtoBytesLen);
bw.flush();
// Now read the response from the server.
try {
line = readLine();
} catch (IOException e) {
throw new IOException(ERR_CONNECTION_READ, e);
}
// We expect a PONG
if (!PONG_PROTO.trim().equals(line)) {
// But it could be something else, like -ERR
// If it's a server error...
if (line.startsWith(_ERR_OP_)) {
// Remove -ERR, trim spaces and quotes, and convert to lower case.
line = normalizeErr(line);
throw new IOException("nats: " + line);
}
// Notify that we got an unexpected protocol.
throw new IOException(String.format("nats: expected '%s', got '%s'", _PONG_OP_, line));
}
// This is where we are truly connected.
status = CONNECTED;
}
// This function is only used during the initial connection process
String readLine() throws IOException {
BufferedReader breader = conn.getBufferedReader();
String line;
line = breader.readLine();
if (line == null) {
throw new EOFException(ERR_CONNECTION_CLOSED);
}
return line;
}
/*
* This method is only used by processPing. It is also used in the gnatsd tests.
*/
void sendProto(byte[] value, int length) throws IOException {
mu.lock();
try {
bw.write(value, 0, length);
kickFlusher();
} finally {
mu.unlock();
}
}
// Generate a connect protocol message, issuing user/password if
// applicable. The lock is assumed to be held upon entering.
String connectProto() {
String userInfo = getUrl().getUserInfo();
String user = null;
String pass = null;
String token = null;
if (userInfo != null) {
// if no password, assume username is authToken
String[] userpass = userInfo.split(":");
if (userpass[0].length() > 0) {
switch (userpass.length) {
case 1:
token = userpass[0];
break;
case 2:
user = userpass[0];
pass = userpass[1];
break;
default:
break;
}
}
} else {
// Take from options (possibly all empty strings)
user = opts.getUsername();
pass = opts.getPassword();
token = opts.getToken();
}
ConnectInfo info = new ConnectInfo(opts.isVerbose(), opts.isPedantic(), user, pass, token,
opts.isSecure(), opts.getConnectionName(), LANG_STRING, version,
ClientProto.CLIENT_PROTO_INFO);
return String.format(CONN_PROTO, info);
}
Control readOp() throws IOException {
// This is only used when creating a connection, so simplify
// life and just create a BufferedReader to read the incoming
// info string.
//
// Do not close the BufferedReader; let TcpConnection manage it.
String str = readLine();
return new Control(str);
}
// waitForExits will wait for all socket watcher threads to
// complete before proceeding.
private void waitForExits() throws InterruptedException {
// Kick old flusher forcefully.
kickFlusher();
if (socketWatchersDoneLatch != null) {
logger.debug("nats: waiting for watcher threads to exit");
socketWatchersDoneLatch.await();
}
}
protected void spinUpSocketWatchers() throws InterruptedException {
// Make sure everything has exited.
waitForExits();
socketWatchersDoneLatch = new CountDownLatch(NUM_WATCHER_THREADS);
socketWatchersStartLatch = new CountDownLatch(NUM_WATCHER_THREADS);
Future task = exec.submit(new Runnable() {
public void run() {
Thread.currentThread().setName(READLOOP);
logger.debug("{} starting...", READLOOP);
socketWatchersStartLatch.countDown();
try {
socketWatchersStartLatch.await();
readLoop();
} catch (InterruptedException e) {
logger.debug("{} interrupted", READLOOP);
Thread.currentThread().interrupt();
} catch (Exception e) {
logger.error("Unexpected exception in {}", READLOOP, e);
} finally {
socketWatchersDoneLatch.countDown();
}
logger.debug("{} exiting", READLOOP);
}
});
tasks.put(READLOOP, task);
task = exec.submit(new Runnable() {
public void run() {
Thread.currentThread().setName(FLUSHER);
logger.debug("{} starting...", FLUSHER);
socketWatchersStartLatch.countDown();
try {
socketWatchersStartLatch.await();
flusher();
} catch (InterruptedException e) {
logger.debug("{} interrupted", FLUSHER);
Thread.currentThread().interrupt();
} catch (Exception e) {
logger.error("Unexpected exception in {}", FLUSHER, e);
} finally {
socketWatchersDoneLatch.countDown();
}
logger.debug("{} exiting", FLUSHER);
}
});
tasks.put(FLUSHER, task);
// resetFlushTimer();
// socketWatchersDoneLatch.countDown();
socketWatchersStartLatch.countDown();
resetPingTimer();
}
void readLoop() throws InterruptedException {
Parser parser;
int len;
boolean sb;
TcpConnection conn = null;
mu.lockInterruptibly();
try {
parser = this.parser;
if (parser.ps == null) {
parser.ps = new Parser.ParseState();
}
} finally {
mu.unlock();
}
// Stack based buffer.
byte[] buffer = new byte[DEFAULT_BUF_SIZE];
while (!Thread.currentThread().isInterrupted()) {
mu.lockInterruptibly();
try {
sb = (closed() || reconnecting());
if (sb) {
parser.ps = new Parser.ParseState();
}
conn = this.conn;
} finally {
mu.unlock();
}
if (sb || conn == null) {
break;
}
try {
len = br.read(buffer);
if (len == -1) {
throw new IOException(ERR_STALE_CONNECTION);
}
parser.parse(buffer, len);
} catch (IOException | ParseException e) {
logger.debug("Exception in readloop(): '{}' (state: {})", e.getMessage(), status);
if (status != CLOSED) {
processOpError(e);
}
break;
}
}
mu.lockInterruptibly();
try {
parser.ps = null;
} finally {
mu.unlock();
}
}
/**
* waitForMsgs waits on the conditional shared with readLoop and processMsg. It is used to
* deliver messages to asynchronous subscribers.
*
* @param sub the asynchronous subscriber
* @throws InterruptedException if the thread is interrupted
*/
void waitForMsgs(AsyncSubscriptionImpl sub) throws InterruptedException {
boolean closed;
long delivered = 0L;
long max;
Message msg;
MessageHandler mcb;
BlockingQueue mch;
while (true) {
sub.lock();
try {
mch = sub.getChannel();
while (mch.size() == 0 && !sub.isClosed()) {
sub.pCond.await();
}
msg = mch.poll();
if (msg != null) {
sub.pMsgs--;
sub.pBytes -= (msg.getData() == null ? 0 : msg.getData().length);
}
mcb = sub.getMessageHandler();
max = sub.max;
closed = sub.isClosed();
if (!closed) {
sub.delivered++;
delivered = sub.delivered;
}
} finally {
sub.unlock();
}
if (closed) {
break;
}
// Deliver the message.
if (msg != null && (max <= 0 || delivered <= max)) {
mcb.onMessage(msg);
}
// If we have hit the max for delivered msgs, remove sub.
if (max > 0 && delivered >= max) {
mu.lock();
try {
removeSub(sub);
} finally {
mu.unlock();
}
break;
}
}
}
/**
* processMsg is called by parse and will place the msg on the appropriate channel/pending queue
* for processing. If the channel is full, or the pending queue is over the pending limits, the
* connection is considered a slow consumer.
*
* @param data the buffer containing the message body
* @param offset the offset within this buffer of the beginning of the message body
* @param length the length of the message body
*/
void processMsg(byte[] data, int offset, int length) {
SubscriptionImpl sub;
mu.lock();
try {
stats.incrementInMsgs();
stats.incrementInBytes(length);
sub = subs.get(parser.ps.ma.sid);
if (sub == null) {
return;
}
// Doing message create outside of the sub's lock to reduce contention.
// It's possible that we end up not using the message, but that's ok.
Message msg = new Message(parser.ps.ma, sub, data, offset, length);
sub.lock();
try {
sub.pMsgs++;
if (sub.pMsgs > sub.pMsgsMax) {
sub.pMsgsMax = sub.pMsgs;
}
sub.pBytes += (msg.getData() == null ? 0 : msg.getData().length);
if (sub.pBytes > sub.pBytesMax) {
sub.pBytesMax = sub.pBytes;
}
// Check for a Slow Consumer
if ((sub.pMsgsLimit > 0 && sub.pMsgs > sub.pMsgsLimit)
|| (sub.pBytesLimit > 0 && sub.pBytes > sub.pBytesLimit)) {
handleSlowConsumer(sub, msg);
} else {
// We use mch for everything, unlike Go client
if (sub.getChannel() != null) {
if (sub.getChannel().add(msg)) {
sub.pCond.signal();
// Clear Slow Consumer status
sub.setSlowConsumer(false);
} else {
handleSlowConsumer(sub, msg);
}
}
}
} finally {
sub.unlock();
}
} finally {
mu.unlock();
}
}
// Assumes you already have the lock
void handleSlowConsumer(SubscriptionImpl sub, Message msg) {
sub.dropped++;
processSlowConsumer(sub);
sub.pMsgs--;
if (msg.getData() != null) {
sub.pBytes -= msg.getData().length;
}
}
void removeSub(SubscriptionImpl sub) {
subs.remove(sub.getSid());
sub.lock();
try {
if (sub.getChannel() != null) {
sub.mch.clear();
sub.mch = null;
}
// Mark as invalid
sub.setConnection(null);
sub.closed = true;
} finally {
sub.unlock();
}
}
// processSlowConsumer will set SlowConsumer state and fire the
// async error handler if registered.
void processSlowConsumer(SubscriptionImpl sub) {
final IOException ex = new IOException(ERR_SLOW_CONSUMER);
final NATSException nex = new NATSException(ex, this, sub);
setLastError(ex);
if (opts.getExceptionHandler() != null && !sub.isSlowConsumer()) {
cbexec.submit(new Runnable() {
public void run() {
opts.getExceptionHandler().onException(nex);
}
});
}
sub.setSlowConsumer(true);
}
void processPermissionsViolation(String err) {
final IOException serverEx = new IOException("nats: " + err);
final NATSException nex = new NATSException(serverEx);
nex.setConnection(this);
setLastError(serverEx);
if (opts.getExceptionHandler() != null) {
cbexec.submit(new Runnable() {
public void run() {
opts.getExceptionHandler().onException(nex);
}
});
}
}
// FIXME: This is a hack
// removeFlushEntry is needed when we need to discard queued up responses
// for our pings as part of a flush call. This happens when we have a flush
// call outstanding and we call close.
boolean removeFlushEntry(BlockingQueue ch) throws InterruptedException {
mu.lockInterruptibly();
try {
if (pongs == null) {
return false;
}
for (BlockingQueue c : pongs) {
if (c.equals(ch)) {
c.clear();
pongs.remove(c);
return true;
}
}
return false;
} finally {
mu.unlock();
}
}
// The lock must be held entering this function.
void sendPing(BlockingQueue ch) {
if (pongs == null) {
pongs = createPongs();
}
if (ch != null) {
pongs.add(ch);
}
try {
bw.write(pingProtoBytes, 0, pingProtoBytesLen);
bw.flush();
} catch (IOException e) {
setLastError(e);
}
}
List> createPongs() {
return new ArrayList>();
}
ScheduledFuture createPingTimer() {
PingTimerTask pinger = new PingTimerTask();
return exec.scheduleWithFixedDelay(pinger, opts.getPingInterval(),
opts.getPingInterval(), TimeUnit.MILLISECONDS);
}
void resetPingTimer() {
mu.lock();
try {
if (ptmr != null) {
ptmr.cancel(true);
tasks.remove(ptmr);
}
if (opts.getPingInterval() > 0) {
ptmr = createPingTimer();
tasks.put("pingtimer", ptmr);
}
} finally {
mu.unlock();
}
}
void writeUnsubProto(SubscriptionImpl sub, long max) throws IOException {
String str = String.format(UNSUB_PROTO, sub.getSid(), max > 0 ? Long.toString(max) : "");
str = str.replaceAll(" +\r\n", "\r\n");
byte[] unsub = str.getBytes();
bw.write(unsub);
}
void unsubscribe(SubscriptionImpl sub, int max) throws IOException {
unsubscribe(sub, (long) max);
}
// unsubscribe performs the low level unsubscribe to the server.
// Use SubscriptionImpl.unsubscribe()
protected void unsubscribe(SubscriptionImpl sub, long max) throws IOException {
mu.lock();
try {
if (isClosed()) {
throw new IllegalStateException(ERR_CONNECTION_CLOSED);
}
SubscriptionImpl subscription = subs.get(sub.getSid());
// already unsubscribed
if (subscription == null) {
return;
}
// If the autounsubscribe max is > 0, set that on the subscription
if (max > 0) {
subscription.setMax(max);
} else {
removeSub(subscription);
}
// We will send all subscriptions when reconnecting
// so that we can suppress here.
if (!reconnecting()) {
writeUnsubProto(subscription, max);
}
kickFlusher();
} finally {
mu.unlock();
}
}
protected void kickFlusher() {
if (bw != null && fch != null) {
fch.offer(true);
}
}
// This is the loop of the flusher thread
protected void flusher() throws InterruptedException {
// snapshot the bw and conn since they can change from underneath of us.
mu.lockInterruptibly();
final OutputStream bw = this.bw;
final TcpConnection conn = this.conn;
final BlockingQueue fch = this.fch;
mu.unlock();
if (conn == null || bw == null) {
return;
}
while (fch.take()) {
mu.lockInterruptibly();
try {
// Check to see if we should bail out.
if (!connected() || connecting() || bw != this.bw || conn != this.conn) {
return;
}
bw.flush();
stats.incrementFlushes();
} catch (IOException e) {
logger.debug("I/O exception encountered during flush");
this.setLastError(e);
} finally {
mu.unlock();
}
Thread.sleep(flushTimerUnit.toMillis(flushTimerInterval));
}
logger.debug("flusher id:{} exiting", Thread.currentThread().getId());
}
/*
* (non-Javadoc)
*
* @see io.nats.client.AbstractConnection#flush(int)
*/
@Override
public void flush(int timeout) throws IOException, InterruptedException {
if (timeout <= 0) {
throw new IllegalArgumentException(ERR_BAD_TIMEOUT);
}
BlockingQueue ch = null;
mu.lockInterruptibly();
try {
if (closed()) {
throw new IllegalStateException(ERR_CONNECTION_CLOSED);
}
ch = createBooleanChannel(1);
sendPing(ch);
} finally {
mu.unlock();
}
Boolean rv = ch.poll(timeout, TimeUnit.MILLISECONDS);
if (rv == null) {
this.removeFlushEntry(ch);
throw new IOException(ERR_TIMEOUT);
} else if (rv) {
ch.clear();
} else {
throw new IllegalStateException(ERR_CONNECTION_CLOSED);
}
}
/// Flush will perform a round trip to the server and return when it
/// receives the internal reply.
@Override
public void flush() throws IOException, InterruptedException {
// 60 second default.
flush(60000);
}
// resendSubscriptions will send our subscription state back to the
// server. Used in reconnects
void resendSubscriptions() {
long adjustedMax = 0L;
for (Map.Entry entry : subs.entrySet()) {
SubscriptionImpl sub = entry.getValue();
sub.lock();
try {
if (sub.max > 0) {
if (sub.delivered < sub.max) {
adjustedMax = sub.max - sub.delivered;
}
// adjustedMax could be 0 here if the number of delivered msgs
// reached the max, if so unsubscribe.
if (adjustedMax == 0) {
// s.mu.unlock();
try {
unsubscribe(sub, 0);
} catch (Exception e) {
/* NOOP */
}
continue;
}
}
} finally {
sub.unlock();
}
sendSubscriptionMessage(sub);
if (adjustedMax > 0) {
try {
// cannot call unsubscribe here. Need to just send proto
writeUnsubProto(sub, adjustedMax);
} catch (Exception e) {
logger.debug("nats: exception while writing UNSUB proto");
}
}
}
}
/**
* subscribe is the internal subscribe function that indicates interest in a subject.
*
* @param subject the subject
* @param queue an optional subscription queue
* @param cb async callback
* @param ch channel
* @return the Subscription object
*/
SubscriptionImpl subscribe(String subject, String queue, MessageHandler cb,
BlockingQueue ch) {
final SubscriptionImpl sub;
mu.lock();
try {
// Check for some error conditions.
if (closed()) {
throw new IllegalStateException(ERR_CONNECTION_CLOSED);
}
if (cb == null && ch == null) {
throw new IllegalArgumentException(ERR_BAD_SUBSCRIPTION);
}
if (cb != null) {
sub = new AsyncSubscriptionImpl(this, subject, queue, cb);
// If we have an async callback, start up a sub specific Runnable to deliver the
// messages
logger.debug("Starting subscription for subject '{}'", subject);
subexec.submit(new Runnable() {
public void run() {
try {
waitForMsgs((AsyncSubscriptionImpl) sub);
} catch (InterruptedException e) {
logger.debug("Interrupted in waitForMsgs");
Thread.currentThread().interrupt();
}
}
});
} else {
sub = new SyncSubscriptionImpl(this, subject, queue);
sub.setChannel(ch);
}
// Sets sid and adds to subs map
addSubscription(sub);
// Send SUB proto
if (!reconnecting()) {
sendSubscriptionMessage(sub);
}
kickFlusher();
return sub;
} finally {
mu.unlock();
}
}
@Override
public SyncSubscription subscribe(String subject) {
return subscribeSync(subject, null);
}
@Override
public SyncSubscription subscribe(String subject, String queue) {
return subscribeSync(subject, queue);
}
@Override
public AsyncSubscription subscribe(String subject, MessageHandler cb) {
return subscribe(subject, null, cb);
}
@Override
public AsyncSubscription subscribe(String subj, String queue, MessageHandler cb) {
return (AsyncSubscriptionImpl) subscribe(subj, queue, cb, null);
}
@Override
@Deprecated
public AsyncSubscription subscribeAsync(String subject, String queue, MessageHandler cb) {
return (AsyncSubscriptionImpl) subscribe(subject, queue, cb, null);
}
@Override
@Deprecated
public AsyncSubscription subscribeAsync(String subj, MessageHandler cb) {
return subscribe(subj, null, cb);
}
private void addSubscription(SubscriptionImpl sub) {
sub.setSid(sidCounter.incrementAndGet());
subs.put(sub.getSid(), sub);
}
@Override
public SyncSubscription subscribeSync(String subject, String queue) {
return (SyncSubscription) subscribe(subject, queue, null,
createMsgChannel());
}
@Override
public SyncSubscription subscribeSync(String subject) {
return (SyncSubscription) subscribe(subject, null, null,
createMsgChannel());
}
// Use low level primitives to build the protocol for the publish
// message.
void writePublishProto(ByteBuffer buffer, byte[] subject, byte[] reply, int msgSize) {
pubProtoBuf.put(subject, 0, subject.length);
if (reply != null) {
pubProtoBuf.put((byte) ' ');
pubProtoBuf.put(reply, 0, reply.length);
}
pubProtoBuf.put((byte) ' ');
byte[] bytes = new byte[12];
int idx = bytes.length;
if (msgSize > 0) {
for (int l = msgSize; l > 0; l /= 10) {
idx--;
bytes[idx] = digits[l % 10];
}
} else {
idx -= 1;
bytes[idx] = digits[0];
}
pubProtoBuf.put(bytes, idx, bytes.length - idx);
pubProtoBuf.put(crlfProtoBytes, 0, crlfProtoBytesLen);
}
// Used for handrolled itoa
static final byte[] digits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9'};
// The internal publish operation sends a protocol data message by queueing into the buffered
// OutputStream and kicking the flush go routine. These writes should be protected.
void publish(byte[] subject, byte[] reply, byte[] data, boolean forceFlush) throws IOException {
int msgSize = (data != null) ? data.length : 0;
mu.lock();
try {
// Proactively reject payloads over the threshold set by server.
if (msgSize > info.getMaxPayload()) {
throw new IllegalArgumentException(ERR_MAX_PAYLOAD);
}
// Since we have the lock, examine directly for a tiny performance
// boost in fastpath
if (closed()) {
throw new IllegalStateException(ERR_CONNECTION_CLOSED);
}
// Check if we are reconnecting, and if so check if
// we have exceeded our reconnect outbound buffer limits.
if (reconnecting()) {
// Flush to underlying buffer
try {
bw.flush();
} catch (IOException e) {
logger.error("I/O exception during flush");
}
if (pending.size() >= opts.getReconnectBufSize()) {
throw new IOException(ERR_RECONNECT_BUF_EXCEEDED);
}
}
// write our pubProtoBuf buffer to the buffered writer.
try {
writePublishProto(pubProtoBuf, subject, reply, msgSize);
} catch (BufferOverflowException e) {
// We can get here if we have very large subjects.
// Expand with some room to spare.
logger.warn("nats: reallocating publish buffer due to overflow");
int resizeAmount = Parser.MAX_CONTROL_LINE_SIZE + subject.length
+ (reply != null ? reply.length : 0);
buildPublishProtocolBuffer(resizeAmount);
writePublishProto(pubProtoBuf, subject, reply, msgSize);
}
try {
bw.write(pubProtoBuf.array(), 0, pubProtoBuf.position());
pubProtoBuf.position(pubPrimBytesLen);
if (msgSize > 0) {
bw.write(data, 0, msgSize);
}
bw.write(crlfProtoBytes, 0, crlfProtoBytesLen);
} catch (IOException e) {
setLastError(e);
return;
}
stats.incrementOutMsgs();
stats.incrementOutBytes(msgSize);
if (forceFlush) {
bw.flush();
stats.incrementFlushes();
} else {
// Opportunistic flush
if (fch.isEmpty()) {
kickFlusher();
}
}
} finally {
mu.unlock();
}
}
// publish can throw a few different unchecked exceptions:
// IllegalStateException, IllegalArgumentException, NullPointerException
@Override
public void publish(String subject, String reply, byte[] data, boolean flush)
throws IOException {
if (subject == null) {
throw new NullPointerException(ERR_BAD_SUBJECT);
}
if (subject.isEmpty()) {
throw new IllegalArgumentException(ERR_BAD_SUBJECT);
}
byte[] subjBytes = subject.getBytes();
byte[] replyBytes = null;
if (reply != null) {
replyBytes = reply.getBytes();
}
publish(subjBytes, replyBytes, data, flush);
}
@Override
public void publish(String subject, String reply, byte[] data) throws IOException {
publish(subject, reply, data, false);
}
@Override
public void publish(String subject, byte[] data) throws IOException {
publish(subject, null, data);
}
@Override
public void publish(Message msg) throws IOException {
publish(msg.getSubjectBytes(), msg.getReplyToBytes(), msg.getData(), false);
}
@Override
public Message request(String subject, byte[] data, long timeout, TimeUnit unit)
throws IOException, InterruptedException {
String inbox = newInbox();
BlockingQueue ch = createMsgChannel(8);
try (SyncSubscription sub = (SyncSubscription) subscribe(inbox, null, null, ch)) {
sub.autoUnsubscribe(1);
publish(subject, inbox, data);
return sub.nextMessage(timeout, unit);
}
}
@Override
public Message request(String subject, byte[] data, long timeout)
throws IOException, InterruptedException {
return request(subject, data, timeout, TimeUnit.MILLISECONDS);
}
@Override
public Message request(String subject, byte[] data) throws IOException, InterruptedException {
return request(subject, data, -1, TimeUnit.MILLISECONDS);
}
@Override
public String newInbox() {
return String.format("%s%s", INBOX_PREFIX, NUID.nextGlobal());
}
@Override
public synchronized Statistics getStats() {
return new Statistics(stats);
}
@Override
public synchronized void resetStats() {
stats.clear();
}
@Override
public synchronized long getMaxPayload() {
return info.getMaxPayload();
}
// Assumes already have the lock
void sendSubscriptionMessage(SubscriptionImpl sub) {
// We will send these for all subs when we reconnect
// so that we can suppress here.
String queue = sub.getQueue();
String subLine = String.format(SUB_PROTO, sub.getSubject(),
(queue != null && !queue.isEmpty()) ? " " + queue : "", sub.getSid());
try {
bw.write(subLine.getBytes());
} catch (IOException e) {
logger.warn("nats: I/O exception while sending subscription message");
}
}
@Override
public ClosedCallback getClosedCallback() {
mu.lock();
try {
return opts.getClosedCallback();
} finally {
mu.unlock();
}
}
@Override
public void setClosedCallback(ClosedCallback cb) {
mu.lock();
try {
opts.closedCb = cb;
} finally {
mu.unlock();
}
}
@Override
public DisconnectedCallback getDisconnectedCallback() {
mu.lock();
try {
return opts.getDisconnectedCallback();
} finally {
mu.unlock();
}
}
@Override
public void setDisconnectedCallback(DisconnectedCallback cb) {
mu.lock();
try {
opts.disconnectedCb = cb;
} finally {
mu.unlock();
}
}
@Override
public ReconnectedCallback getReconnectedCallback() {
mu.lock();
try {
return opts.getReconnectedCallback();
} finally {
mu.unlock();
}
}
@Override
public void setReconnectedCallback(ReconnectedCallback cb) {
mu.lock();
try {
opts.reconnectedCb = cb;
} finally {
mu.unlock();
}
}
@Override
public ExceptionHandler getExceptionHandler() {
mu.lock();
try {
return opts.getExceptionHandler();
} finally {
mu.unlock();
}
}
@Override
public void setExceptionHandler(ExceptionHandler exceptionHandler) {
mu.lock();
try {
opts.asyncErrorCb = exceptionHandler;
} finally {
mu.unlock();
}
}
@Override
public String getConnectedUrl() {
mu.lock();
try {
if (status != CONNECTED) {
return null;
}
return getUrl().toString();
} finally {
mu.unlock();
}
}
@Override
public String getConnectedServerId() {
mu.lock();
try {
if (status != CONNECTED) {
return null;
}
return info.getId();
} finally {
mu.unlock();
}
}
@Override
public ConnState getState() {
mu.lock();
try {
return this.status;
} finally {
mu.unlock();
}
}
@Override
public ServerInfo getConnectedServerInfo() {
return this.info;
}
void setConnectedServerInfo(ServerInfo info) {
this.info = info;
}
@Override
public Exception getLastException() {
return lastEx;
}
void setLastError(Exception err) {
this.lastEx = err;
}
Options getOptions() {
return this.opts;
}
void setOptions(Options options) {
this.opts = options;
}
void setPending(ByteArrayOutputStream pending) {
this.pending = pending;
}
ByteArrayOutputStream getPending() {
return this.pending;
}
void setOutputStream(OutputStream out) {
mu.lock();
try {
this.bw = out;
} finally {
mu.unlock();
}
}
OutputStream getOutputStream() {
return bw;
}
void setInputStream(InputStream in) {
mu.lock();
try {
this.br = in;
} finally {
mu.unlock();
}
}
InputStream getInputStream() {
return br;
}
List> getPongs() {
return pongs;
}
void setPongs(List> pongs) {
this.pongs = pongs;
}
Map getSubs() {
return subs;
}
void setSubs(Map subs) {
this.subs = subs;
}
// for testing purposes
List getServerPool() {
return this.srvPool;
}
// for testing purposes
void setServerPool(List pool) {
this.srvPool = pool;
}
@Override
public int getPendingByteCount() {
int rv = 0;
if (getPending() != null) {
rv = getPending().size();
}
return rv;
}
protected void setFlushChannel(BlockingQueue fch) {
this.fch = fch;
}
protected BlockingQueue getFlushChannel() {
return fch;
}
void setTcpConnection(TcpConnection conn) {
this.conn = conn;
}
TcpConnection getTcpConnection() {
return this.conn;
}
void setTcpConnectionFactory(TcpConnectionFactory factory) {
this.tcf = factory;
}
TcpConnectionFactory getTcpConnectionFactory() {
return this.tcf;
}
URI getUrl() {
return url;
}
void setUrl(URI url) {
this.url = url;
}
int getActualPingsOutstanding() {
return pout;
}
void setActualPingsOutstanding(int pout) {
this.pout = pout;
}
ScheduledFuture getPingTimer() {
return ptmr;
}
void setPingTimer(ScheduledFuture ptmr) {
this.ptmr = ptmr;
}
void setParser(Parser parser) {
this.parser = parser;
}
Parser getParser() {
return parser;
}
String[] getServers(boolean implicitOnly) {
List serversList = new ArrayList(srvPool.size());
for (Srv aSrvPool : srvPool) {
if (implicitOnly && !aSrvPool.isImplicit()) {
continue;
}
URI url = aSrvPool.url;
String schemeUrl =
String.format("%s://%s:%d", url.getScheme(), url.getHost(), url.getPort());
serversList.add(schemeUrl);
}
String[] servers = new String[serversList.size()];
return serversList.toArray(servers);
}
@Override
public String[] getServers() {
mu.lock();
try {
return getServers(false);
} finally {
mu.unlock();
}
}
@Override
public String[] getDiscoveredServers() {
mu.lock();
try {
return getServers(true);
} finally {
mu.unlock();
}
}
@Override
public boolean isAuthRequired() {
mu.lock();
try {
return info.isAuthRequired();
} finally {
mu.unlock();
}
}
@Override
public boolean isTlsRequired() {
mu.lock();
try {
return info.isTlsRequired();
} finally {
mu.unlock();
}
}
static class Control {
String op = null;
String args = null;
Control(String line) {
if (line == null) {
return;
}
String[] parts = line.split(" ", 2);
switch (parts.length) {
case 1:
op = parts[0].trim();
break;
case 2:
op = parts[0].trim();
args = parts[1].trim();
if (args.isEmpty()) {
args = null;
}
break;
default:
}
}
public String toString() {
return "{op=" + op + ", args=" + args + "}";
}
}
static class ConnectInfo {
@SerializedName("verbose")
private final Boolean verbose;
@SerializedName("pedantic")
private final Boolean pedantic;
@SerializedName("user")
private final String user;
@SerializedName("pass")
private final String pass;
@SerializedName("auth_token")
private final String token;
@SerializedName("tls_required")
private final Boolean tlsRequired;
@SerializedName("name")
private final String name;
@SerializedName("lang")
private String lang = ConnectionImpl.LANG_STRING;
@SerializedName("version")
private String version;
@SerializedName("protocol")
private final int protocol;
private final transient Gson gson = new GsonBuilder().create();
public ConnectInfo(boolean verbose, boolean pedantic, String username, String password,
String token, boolean secure, String connectionName, String lang,
String version, ClientProto proto) {
this.verbose = verbose;
this.pedantic = pedantic;
this.user = username;
this.pass = password;
this.token = token;
this.tlsRequired = secure;
this.name = connectionName;
this.lang = lang;
this.version = version;
this.protocol = proto.getValue();
}
public String toString() {
return gson.toJson(this);
}
}
static class Srv {
URI url = null;
int reconnects = 0;
long lastAttemptNanos = 0L;
boolean implicit = false;
Srv(URI url, boolean implicit) {
this.url = url;
this.implicit = implicit;
}
boolean isImplicit() {
return implicit;
}
// Mark the last attempt to connect to this Srv
void updateLastAttempt() {
lastAttemptNanos = System.nanoTime();
}
// Returns time since last attempt, in msec
long timeSinceLastAttempt() {
return (TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - lastAttemptNanos));
}
public String toString() {
return String.format(
"{url=%s, reconnects=%d, timeSinceLastAttempt=%dms}",
url.toString(), reconnects, timeSinceLastAttempt());
}
}
// This will fire periodically and send a client origin
// ping to the server. Will also check that we have received
// responses from the server.
class PingTimerTask extends TimerTask {
public void run() {
boolean stale = false;
mu.lock();
try {
if (!connected()) {
return;
}
// Check for violation
setActualPingsOutstanding(getActualPingsOutstanding() + 1);
if (getActualPingsOutstanding() > opts.getMaxPingsOut()) {
stale = true;
return;
}
sendPing(null);
} finally {
mu.unlock();
if (stale) {
try {
processOpError(new IOException(ERR_STALE_CONNECTION));
} catch (InterruptedException e) {
logger.warn("Interrupted");
Thread.currentThread().interrupt();
}
}
}
}
}
}