public <T extends TransportResponse> void sendRequest(
final DiscoveryNode node,
final String action,
final TransportRequest request,
final TransportRequestOptions options,
TransportResponseHandler<T> handler) {
if (node == null) {
throw new ElasticsearchIllegalStateException("can't send request to a null node");
}
final long requestId = newRequestId();
TimeoutHandler timeoutHandler = null;
try {
clientHandlers.put(requestId, new RequestHolder<>(handler, node, action, timeoutHandler));
if (started.get() == false) {
// if we are not started the exception handling will remove the RequestHolder again and
// calls the handler to notify the caller.
// it will only notify if the toStop code hasn't done the work yet.
throw new TransportException("TransportService is closed stopped can't send request");
}
if (options.timeout() != null) {
timeoutHandler = new TimeoutHandler(requestId);
timeoutHandler.future =
threadPool.schedule(options.timeout(), ThreadPool.Names.GENERIC, timeoutHandler);
}
transport.sendRequest(node, requestId, action, request, options);
} catch (final Throwable e) {
// usually happen either because we failed to connect to the node
// or because we failed serializing the message
final RequestHolder holderToNotify = clientHandlers.remove(requestId);
// if the scheduler raise a EsRejectedExecutionException (due to shutdown), we may have a
// timeout handler, but no future
if (timeoutHandler != null) {
FutureUtils.cancel(timeoutHandler.future);
}
// If holderToNotify == null then handler has already been taken care of.
if (holderToNotify != null) {
// callback that an exception happened, but on a different thread since we don't
// want handlers to worry about stack overflows
final SendRequestTransportException sendRequestException =
new SendRequestTransportException(node, action, e);
threadPool
.executor(ThreadPool.Names.GENERIC)
.execute(
new Runnable() {
@Override
public void run() {
holderToNotify.handler().handleException(sendRequestException);
}
});
}
}
}
