public void process(Exchange exchange) throws Exception {
if (output == null) {
// no output then just return
return;
}
AsyncProcessorHelper.process(this, exchange);
}
private void doProcessParallel(final ProcessorExchangePair pair) throws Exception {
final Exchange exchange = pair.getExchange();
Processor processor = pair.getProcessor();
Producer producer = pair.getProducer();
TracedRouteNodes traced =
exchange.getUnitOfWork() != null ? exchange.getUnitOfWork().getTracedRouteNodes() : null;
// compute time taken if sending to another endpoint
StopWatch watch = null;
if (producer != null) {
watch = new StopWatch();
}
try {
// prepare tracing starting from a new block
if (traced != null) {
traced.pushBlock();
}
if (producer != null) {
EventHelper.notifyExchangeSending(exchange.getContext(), exchange, producer.getEndpoint());
}
// let the prepared process it, remember to begin the exchange pair
AsyncProcessor async = AsyncProcessorConverterHelper.convert(processor);
pair.begin();
// we invoke it synchronously as parallel async routing is too hard
AsyncProcessorHelper.process(async, exchange);
} finally {
pair.done();
// pop the block so by next round we have the same staring point and thus the tracing looks
// accurate
if (traced != null) {
traced.popBlock();
}
if (producer != null) {
long timeTaken = watch.stop();
Endpoint endpoint = producer.getEndpoint();
// emit event that the exchange was sent to the endpoint
// this is okay to do here in the finally block, as the processing is not using the async
// routing engine
// ( we invoke it synchronously as parallel async routing is too hard)
EventHelper.notifyExchangeSent(exchange.getContext(), exchange, endpoint, timeTaken);
}
}
}
public void process(Exchange exchange) throws Exception {
AsyncProcessorHelper.process(this, exchange);
}
/** All redelivery attempts failed so move the exchange to the dead letter queue */
protected boolean deliverToFailureProcessor(
final Processor processor,
final Exchange exchange,
final RedeliveryData data,
final AsyncCallback callback) {
boolean sync = true;
Exception caught = exchange.getException();
// we did not success with the redelivery so now we let the failure processor handle it
// clear exception as we let the failure processor handle it
exchange.setException(null);
boolean handled = false;
// regard both handled or continued as being handled
if (shouldHandled(exchange, data) || shouldContinue(exchange, data)) {
// its handled then remove traces of redelivery attempted
exchange.getIn().removeHeader(Exchange.REDELIVERED);
exchange.getIn().removeHeader(Exchange.REDELIVERY_COUNTER);
exchange.getIn().removeHeader(Exchange.REDELIVERY_MAX_COUNTER);
handled = true;
} else {
// must decrement the redelivery counter as we didn't process the redelivery but is
// handling by the failure handler. So we must -1 to not let the counter be out-of-sync
decrementRedeliveryCounter(exchange);
}
// is the a failure processor to process the Exchange
if (processor != null) {
// prepare original IN body if it should be moved instead of current body
if (data.useOriginalInMessage) {
log.trace("Using the original IN message instead of current");
Message original = exchange.getUnitOfWork().getOriginalInMessage();
exchange.setIn(original);
if (exchange.hasOut()) {
log.trace("Removing the out message to avoid some uncertain behavior");
exchange.setOut(null);
}
}
// reset cached streams so they can be read again
MessageHelper.resetStreamCache(exchange.getIn());
log.trace("Failure processor {} is processing Exchange: {}", processor, exchange);
// store the last to endpoint as the failure endpoint
exchange.setProperty(Exchange.FAILURE_ENDPOINT, exchange.getProperty(Exchange.TO_ENDPOINT));
// the failure processor could also be asynchronous
AsyncProcessor afp = AsyncProcessorTypeConverter.convert(processor);
sync =
AsyncProcessorHelper.process(
afp,
exchange,
new AsyncCallback() {
public void done(boolean sync) {
log.trace(
"Failure processor done: {} processing Exchange: {}", processor, exchange);
try {
prepareExchangeAfterFailure(exchange, data);
// fire event as we had a failure processor to handle it, which there is a event
// for
boolean deadLetterChannel =
processor == data.deadLetterProcessor && data.deadLetterProcessor != null;
EventHelper.notifyExchangeFailureHandled(
exchange.getContext(), exchange, processor, deadLetterChannel);
} finally {
// if the fault was handled asynchronously, this should be reflected in the
// callback as well
data.sync &= sync;
callback.done(data.sync);
}
}
});
} else {
try {
// no processor but we need to prepare after failure as well
prepareExchangeAfterFailure(exchange, data);
} finally {
// callback we are done
callback.done(data.sync);
}
}
// create log message
String msg = "Failed delivery for exchangeId: " + exchange.getExchangeId();
msg =
msg
+ ". Exhausted after delivery attempt: "
+ data.redeliveryCounter
+ " caught: "
+ caught;
if (processor != null) {
msg = msg + ". Processed by failure processor: " + processor;
}
// log that we failed delivery as we are exhausted
logFailedDelivery(false, handled, false, exchange, msg, data, null);
return sync;
}
/** Process the exchange using redelivery error handling. */
protected boolean processErrorHandler(
final Exchange exchange, final AsyncCallback callback, final RedeliveryData data) {
// do a defensive copy of the original Exchange, which is needed for redelivery so we can ensure
// the
// original Exchange is being redelivered, and not a mutated Exchange
data.original = defensiveCopyExchangeIfNeeded(exchange);
// use looping to have redelivery attempts
while (true) {
// can we still run
if (!isRunAllowed()) {
if (exchange.getException() == null) {
exchange.setException(new RejectedExecutionException());
}
// we cannot process so invoke callback
callback.done(data.sync);
return data.sync;
}
// did previous processing cause an exception?
boolean handle = shouldHandleException(exchange);
if (handle) {
handleException(exchange, data);
}
// compute if we are exhausted or not
boolean exhausted = isExhausted(exchange, data);
if (exhausted) {
Processor target = null;
boolean deliver = true;
// the unit of work may have an optional callback associated we need to leverage
SubUnitOfWorkCallback uowCallback = exchange.getUnitOfWork().getSubUnitOfWorkCallback();
if (uowCallback != null) {
// signal to the callback we are exhausted
uowCallback.onExhausted(exchange);
// do not deliver to the failure processor as its been handled by the callback instead
deliver = false;
}
if (deliver) {
// should deliver to failure processor (either from onException or the dead letter
// channel)
target = data.failureProcessor != null ? data.failureProcessor : data.deadLetterProcessor;
}
// we should always invoke the deliverToFailureProcessor as it prepares, logs and does a
// fair
// bit of work for exhausted exchanges (its only the target processor which may be null if
// handled by a savepoint)
boolean sync = deliverToFailureProcessor(target, exchange, data, callback);
// we are breaking out
return sync;
}
if (data.redeliveryCounter > 0) {
// calculate delay
data.redeliveryDelay =
data.currentRedeliveryPolicy.calculateRedeliveryDelay(
data.redeliveryDelay, data.redeliveryCounter);
if (data.redeliveryDelay > 0) {
// okay there is a delay so create a scheduled task to have it executed in the future
if (data.currentRedeliveryPolicy.isAsyncDelayedRedelivery() && !exchange.isTransacted()) {
// let the RedeliverTask be the logic which tries to redeliver the Exchange which we can
// used a scheduler to
// have it being executed in the future, or immediately
// we are continuing asynchronously
// mark we are routing async from now and that this redelivery task came from a
// synchronous routing
data.sync = false;
data.redeliverFromSync = true;
AsyncRedeliveryTask task = new AsyncRedeliveryTask(exchange, callback, data);
// schedule the redelivery task
if (log.isTraceEnabled()) {
log.trace(
"Scheduling redelivery task to run in {} millis for exchangeId: {}",
data.redeliveryDelay,
exchange.getExchangeId());
}
executorService.schedule(task, data.redeliveryDelay, TimeUnit.MILLISECONDS);
return false;
} else {
// async delayed redelivery was disabled or we are transacted so we must be synchronous
// as the transaction manager requires to execute in the same thread context
try {
data.currentRedeliveryPolicy.sleep(data.redeliveryDelay);
} catch (InterruptedException e) {
// we was interrupted so break out
exchange.setException(e);
// mark the exchange to stop continue routing when interrupted
// as we do not want to continue routing (for example a task has been cancelled)
exchange.setProperty(Exchange.ROUTE_STOP, Boolean.TRUE);
callback.done(data.sync);
return data.sync;
}
}
}
// prepare for redelivery
prepareExchangeForRedelivery(exchange, data);
// letting onRedeliver be executed
deliverToOnRedeliveryProcessor(exchange, data);
// emmit event we are doing redelivery
EventHelper.notifyExchangeRedelivery(
exchange.getContext(), exchange, data.redeliveryCounter);
}
// process the exchange (also redelivery)
boolean sync =
AsyncProcessorHelper.process(
outputAsync,
exchange,
new AsyncCallback() {
public void done(boolean sync) {
// this callback should only handle the async case
if (sync) {
return;
}
// mark we are in async mode now
data.sync = false;
// if we are done then notify callback and exit
if (isDone(exchange)) {
callback.done(sync);
return;
}
// error occurred so loop back around which we do by invoking the
// processAsyncErrorHandler
// method which takes care of this in a asynchronous manner
processAsyncErrorHandler(exchange, callback, data);
}
});
if (!sync) {
// the remainder of the Exchange is being processed asynchronously so we should return
return false;
}
// we continue to route synchronously
// if we are done then notify callback and exit
boolean done = isDone(exchange);
if (done) {
callback.done(true);
return true;
}
// error occurred so loop back around.....
}
}
public Boolean call() throws Exception {
// prepare for redelivery
prepareExchangeForRedelivery(exchange, data);
// letting onRedeliver be executed at first
deliverToOnRedeliveryProcessor(exchange, data);
if (log.isTraceEnabled()) {
log.trace(
"Redelivering exchangeId: {} -> {} for Exchange: {}",
new Object[] {exchange.getExchangeId(), outputAsync, exchange});
}
// emmit event we are doing redelivery
EventHelper.notifyExchangeRedelivery(exchange.getContext(), exchange, data.redeliveryCounter);
// process the exchange (also redelivery)
boolean sync;
if (data.redeliverFromSync) {
// this redelivery task was scheduled from synchronous, which we forced to be asynchronous
// from
// this error handler, which means we have to invoke the callback with false, to have the
// callback
// be notified when we are done
sync =
AsyncProcessorHelper.process(
outputAsync,
exchange,
new AsyncCallback() {
public void done(boolean doneSync) {
log.trace(
"Redelivering exchangeId: {} done sync: {}",
exchange.getExchangeId(),
doneSync);
// mark we are in sync mode now
data.sync = false;
// only process if the exchange hasn't failed
// and it has not been handled by the error processor
if (isDone(exchange)) {
callback.done(false);
return;
}
// error occurred so loop back around which we do by invoking the
// processAsyncErrorHandler
processAsyncErrorHandler(exchange, callback, data);
}
});
} else {
// this redelivery task was scheduled from asynchronous, which means we should only
// handle when the asynchronous task was done
sync =
AsyncProcessorHelper.process(
outputAsync,
exchange,
new AsyncCallback() {
public void done(boolean doneSync) {
log.trace(
"Redelivering exchangeId: {} done sync: {}",
exchange.getExchangeId(),
doneSync);
// this callback should only handle the async case
if (doneSync) {
return;
}
// mark we are in async mode now
data.sync = false;
// only process if the exchange hasn't failed
// and it has not been handled by the error processor
if (isDone(exchange)) {
callback.done(doneSync);
return;
}
// error occurred so loop back around which we do by invoking the
// processAsyncErrorHandler
processAsyncErrorHandler(exchange, callback, data);
}
});
}
return sync;
}
