rpc.async_output

Event name

rpc.async_output

Constant

RpcEvent::OUTPUT_ASYNC

Class

RpcAsyncOutputEvent

Properties

RpcRequest $rpcRequest, RpcBatchRequest $batchRequest, string $output

Dispatched in the parent batch process in process mode (batch.process: true) when the ufo:rpc:process child process has finished. $output is the raw process output (the response JSON).

Not dispatched in inline batch mode and for single requests.

Built-in listeners

Priority	Listener	What it does
10	`AsyncServerEventListener::process`	Parses `$output` into a response (empty or invalid output — error), adds it to the batch and always stops propagation

What can be changed

A listener with a priority above 10 can change $event->output before parsing.
Listeners with a priority of 10 and below are not called.
Do not stop propagation above 10: the item will get no response and will most likely disappear from the batch result.

Usage examples

diagnostics: logging the raw output of child processes to find the cause of "Asynchronous request does not respond";
metrics of duration and response size of batch items.

#[AsEventListener(RpcEvent::OUTPUT_ASYNC, priority: 100)]
final class BatchOutputLogger
{
    public function __construct(private LoggerInterface $logger) {}

    public function __invoke(RpcAsyncOutputEvent $event): void
    {
        $this->logger->debug('batch item output', [
            'method' => $event->rpcRequest->getMethod(),
            'bytes' => strlen($event->output),
        ]);
    }
}