public boolean addServer(GearmanJobServerConnection conn)
throws IllegalArgumentException, IllegalStateException {
if (conn == null) {
throw new IllegalArgumentException("Connection can not be null");
}
// this is a sub-optimal way to look for dups, but addJobServer
// ops should be infrequent enough that this should be a big penalty
for (GearmanJobServerSession sess : sessionMap.values()) {
if (sess.getConnection().equals(conn)) {
return true;
}
}
GearmanJobServerSession session = new GearmanJobServerSession(conn);
if (ioAvailable == null) {
try {
ioAvailable = Selector.open();
} catch (IOException ioe) {
LOG.warn("Failed to connect to job server " + conn + ".", ioe);
return false;
}
}
try {
session.initSession(ioAvailable, this);
} catch (IOException ioe) {
LOG.warn("Failed to initialize session with job server " + conn + ".", ioe);
return false;
}
SelectionKey key = session.getSelectionKey();
if (key == null) {
String msg =
"Session "
+ session
+ " has a null "
+ "selection key. Server will not be added to worker.";
LOG.warn(msg);
throw new IllegalStateException(msg);
}
sessionMap.put(key, session);
GearmanPacket p =
new GearmanPacketImpl(
GearmanPacketMagic.REQ, GearmanPacketType.SET_CLIENT_ID, ByteUtils.toUTF8Bytes(id));
session.submitTask(new GearmanTask(p));
for (FunctionDefinition def : functionMap.values()) {
p = generateCanDoPacket(def);
session.submitTask(new GearmanTask(p)); // NOPMD
}
p = new GearmanPacketImpl(GearmanPacketMagic.REQ, getGrabJobPacketType(), new byte[0]);
GearmanTask gsr = new GearmanTask(new GrabJobEventHandler(session), p);
taskMap.put(session, gsr);
session.submitTask(gsr);
LOG.debug("Added server " + conn + " to worker " + this);
return true;
}
private void addNewJob(GearmanSessionEvent event) {
byte[] handle, data, functionNameBytes, unique;
GearmanPacket p = event.getPacket();
GearmanJobServerSession sess = event.getSession();
String functionName;
handle = p.getDataComponentValue(GearmanPacket.DataComponentName.JOB_HANDLE);
functionNameBytes = p.getDataComponentValue(GearmanPacket.DataComponentName.FUNCTION_NAME);
data = p.getDataComponentValue(GearmanPacket.DataComponentName.DATA);
unique = p.getDataComponentValue(DataComponentName.UNIQUE_ID);
functionName = ByteUtils.fromUTF8Bytes(functionNameBytes);
FunctionDefinition def = functionMap.get(functionName);
if (def == null) {
GearmanTask gsr =
new GearmanTask(
new GearmanPacketImpl(GearmanPacketMagic.REQ, GearmanPacketType.WORK_FAIL, handle));
sess.submitTask(gsr);
} else {
GearmanFunction function = def.getFactory().getFunction();
function.setData(data);
function.setJobHandle(handle);
function.registerEventListener(sess);
if (unique != null && unique.length > 0) {
function.setUniqueId(unique);
}
functionList.add(function);
}
}
public void handleSessionEvent(GearmanSessionEvent event)
throws IllegalArgumentException, IllegalStateException {
GearmanPacket p = event.getPacket();
GearmanJobServerSession s = event.getSession();
GearmanPacketType t = p.getPacketType();
LOG.debug(
"Worker "
+ this
+ " handling session event"
+ " ( Session = "
+ s
+ " Event = "
+ t
+ " )");
switch (t) {
case JOB_ASSIGN:
// TODO Figure out what the right behavior is if JobUUIDRequired was false when we submitted
// but is now true
taskMap.remove(s);
addNewJob(event);
break;
case JOB_ASSIGN_UNIQ:
// TODO Figure out what the right behavior is if JobUUIDRequired was true when we submitted
// but is now false
taskMap.remove(s);
addNewJob(event);
break;
case NOOP:
taskMap.remove(s);
break;
case NO_JOB:
GearmanTask preSleepTask =
new GearmanTask(
new GrabJobEventHandler(s),
new GearmanPacketImpl(
GearmanPacketMagic.REQ, GearmanPacketType.PRE_SLEEP, new byte[0]));
taskMap.put(s, preSleepTask);
s.submitTask(preSleepTask);
break;
case ECHO_RES:
break;
case OPTION_RES:
break;
case ERROR:
s.closeSession();
break;
default:
LOG.warn(
"Received unknown packet type " + t + " from session " + s + ". Closing connection.");
s.closeSession();
}
}
private GearmanJobStatus updateJobStatus(byte[] jobhandle, GearmanJobServerSession session)
throws IOException, IllegalStateException, GearmanException {
if (!runState.equals(state.RUNNING)) {
throw new IllegalStateException(CLIENT_NOT_ACTIVE);
}
if (jobhandle == null || jobhandle.length == 0) {
throw new IllegalStateException("Invalid job handle. Handle must" + " not be null nor empty");
}
GearmanPacket statusRequest =
new GearmanPacketImpl(GearmanPacketMagic.REQ, GearmanPacketType.GET_STATUS, jobhandle);
GearmanServerResponseHandler handler =
(GearmanServerResponseHandler) new GearmanJobStatusImpl();
GearmanTask t = new GearmanTask(handler, statusRequest);
session.submitTask(t);
if (!driveRequestTillState(t, GearmanTask.State.FINISHED)) {
throw new GearmanException(
"Failed to execute jobstatus request " + t + " to session " + session);
}
return (GearmanJobStatus) handler;
}
private boolean setForwardExceptions(GearmanJobServerSession session) {
GearmanServerResponseHandler optionReqHandler =
new GearmanServerResponseHandler() {
boolean isDone = false;
public boolean isDone() {
return isDone;
}
public void handleEvent(GearmanPacket event) throws GearmanException {
GearmanPacketType type = event.getPacketType();
if (type.equals(GearmanPacketType.OPTION_RES)
&& Arrays.equals(EXCEPTIONS, event.getData())) {
isDone = true;
}
}
};
GearmanTask setExceptionsTask =
new GearmanTask(
optionReqHandler,
new GearmanPacketImpl(
GearmanPacketMagic.REQ, GearmanPacketType.OPTION_REQ, EXCEPTIONS));
session.submitTask(setExceptionsTask);
Exception e = null;
boolean success = false;
try {
success = driveRequestTillState(setExceptionsTask, GearmanTask.State.FINISHED);
} catch (IOException ioe) {
e = ioe;
}
if (!success) {
if (e != null) {
LOG.info("Failed to set forward-exceptions option to " + session.getConnection(), e);
} else {
LOG.info("Failed to set forward-exceptions option to " + session.getConnection());
}
return false;
}
return true;
}
public byte[] echo(byte[] data) throws IOException, GearmanException {
if (!runState.equals(state.RUNNING)) {
throw new IllegalStateException(CLIENT_NOT_ACTIVE);
}
GearmanPacket echoRequest =
new GearmanPacketImpl(GearmanPacketMagic.REQ, GearmanPacketType.ECHO_REQ, data);
GearmanEchoResponseHandler handler = new GearmanEchoResponseHandler();
GearmanTask t = new GearmanTask(handler, echoRequest);
GearmanJobServerSession session = getSessionForTask();
session.submitTask(t);
LOG.info(
"Client "
+ this
+ " has submitted echo request "
+ "(payload = "
+ ByteUtils.toHex(data)
+ " to session "
+ session);
if (!driveRequestTillState(t, GearmanTask.State.FINISHED)) {
throw new GearmanException("Failed to execute echo request " + t + " to session " + session);
}
LOG.info("Client " + this + " has completed echo request " + "to session " + session);
return handler.getResults();
}
public <T> Future<T> submit(Callable<T> task) {
if (task == null) {
throw new IllegalStateException("Null task was submitted to " + "gearman client");
}
if (!runState.equals(state.RUNNING)) {
throw new RejectedExecutionException("Client has been shutdown");
}
if (!(task instanceof GearmanServerResponseHandler)) {
throw new RejectedExecutionException(
"Task must implement the "
+ GearmanServerResponseHandler.class
+ " interface to"
+ " submitted to this client");
}
GearmanJobImpl job = (GearmanJobImpl) task;
GearmanServerResponseHandler handler = (GearmanServerResponseHandler) job;
if (job.isDone()) {
throw new RejectedExecutionException("Task can not be resubmitted ");
}
GearmanJobServerSession session = null;
try {
session = getSessionForTask();
} catch (IOException ioe) {
throw new RejectedExecutionException(ioe);
}
job.setJobServerSession(session);
GearmanPacket submitRequest = getPacketFromJob(job);
GearmanTask submittedJob = new GearmanTask(handler, submitRequest);
session.submitTask(submittedJob);
LOG.info(
"Client "
+ this
+ " has submitted job "
+ job
+ // NOPMD
" to session "
+ session
+ ". Job has been added to the "
+ // NOPMD
"active job queue");
try {
jobAwatingCreation = job;
if (!(driveRequestTillState(submittedJob, GearmanTask.State.RUNNING))) {
throw new RejectedExecutionException(
"Timed out waiting for" + " submission of " + job + " to complete");
}
} catch (IOException ioe) {
LOG.warn("Client " + this + " encounted an " + "IOException while drivingIO", ioe);
throw new RejectedExecutionException(
"Failed to successfully " + "submit" + job + " due to IOException", ioe);
} finally {
jobAwatingCreation = null;
}
return (Future<T>) job;
}
private void sendToAll(GearmanServerResponseHandler handler, GearmanPacket p) {
GearmanTask gsr = new GearmanTask(handler, p);
for (GearmanJobServerSession sess : sessionMap.values()) {
sess.submitTask(gsr);
}
}
public void work() {
if (!state.equals(State.IDLE)) {
throw new IllegalStateException(
"Can not call work while worker " + "is running or shutting down");
}
state = State.RUNNING;
// a map keeping track of sessions with connection errors
// (to avoid printing an error about them in every reconnect attempt)
Map<GearmanJobServerSession, Boolean> havingConnectionError =
new HashMap<GearmanJobServerSession, Boolean>();
while (isRunning()) {
// look for sessions which have been disconnected and attempt to reconnect.
for (Iterator<GearmanJobServerSession> iter = sessionMap.values().iterator();
iter.hasNext(); ) {
GearmanJobServerSession sess = iter.next();
if (!sess.isInitialized()) {
try {
// reconnect, unregister old selection key and register new one
SelectionKey oldKey = sess.isInitialized() ? sess.getSelectionKey() : null;
sess.initSession(ioAvailable, this);
if (oldKey != null) {
iter.remove();
}
sessionMap.put(sess.getSelectionKey(), sess);
// register all functions with the newly reconnected server
for (FunctionDefinition d : functionMap.values()) {
GearmanTask gsr = new GearmanTask(null, generateCanDoPacket(d));
sess.submitTask(gsr);
}
GearmanPacket p =
new GearmanPacketImpl(
GearmanPacketMagic.REQ,
GearmanPacketType.SET_CLIENT_ID,
ByteUtils.toUTF8Bytes(id));
sess.submitTask(new GearmanTask(p));
GearmanTask sessTask =
new GearmanTask(
new GrabJobEventHandler(sess),
new GearmanPacketImpl(
GearmanPacketMagic.REQ, getGrabJobPacketType(), new byte[0]));
sess.submitTask(sessTask);
sess.driveSessionIO();
// log reconnection message
if (havingConnectionError.get(sess)) {
LOG.info("Re-established connection to " + sess.getConnection().toString());
}
havingConnectionError.put(sess, false);
} catch (IOException e) {
if (!havingConnectionError.get(sess)) {
LOG.warn("Error connecting to " + sess + ", will keep trying..");
}
havingConnectionError.put(sess, true);
try {
Thread.sleep(50);
} catch (InterruptedException e1) {
}
}
} else {
havingConnectionError.put(sess, false);
}
}
for (GearmanJobServerSession sess : sessionMap.values()) {
// if still disconnected, skip
if (!sess.isInitialized()) {
continue;
}
int interestOps = SelectionKey.OP_READ;
if (sess.sessionHasDataToWrite()) {
interestOps |= SelectionKey.OP_WRITE;
}
sess.getSelectionKey().interestOps(interestOps);
}
try {
ioAvailable.select(1);
} catch (IOException io) {
LOG.warn("Receieved IOException while" + " selecting for IO", io);
}
for (SelectionKey key : ioAvailable.selectedKeys()) {
GearmanJobServerSession sess = sessionMap.get(key);
if (sess == null) {
LOG.warn("Worker does not have " + "session for key " + key);
continue;
}
if (!sess.isInitialized()) {
continue;
}
try {
GearmanTask sessTask = taskMap.get(sess);
if (sessTask == null) {
sessTask =
new GearmanTask( // NOPMD
new GrabJobEventHandler(sess),
new GearmanPacketImpl(
GearmanPacketMagic.REQ, getGrabJobPacketType(), new byte[0]));
taskMap.put(sess, sessTask);
sess.submitTask(sessTask);
LOG.debug(
"Worker: "
+ this
+ " submitted a "
+ sessTask.getRequestPacket().getPacketType()
+ " to session: "
+ sess);
}
sess.driveSessionIO();
// For the time being we will execute the jobs synchronously
// in the future, I expect to change this.
if (!functionList.isEmpty()) {
GearmanFunction fun = functionList.remove();
submitFunction(fun);
statistics();
}
} catch (IOException ioe) {
LOG.warn("Received IOException while driving" + " IO on session " + sess, ioe);
sess.closeSession();
continue;
}
}
}
shutDownWorker(true);
}