Events

Each query dispatches events through the Symfony event dispatcher, to plug metrics, tracing or alerting without decorating the GraphQL client.

Event	Dispatched	Trace content
`QueryStartedEvent`	before the query is sent	id, query, variables, AST
`QueryExecutedEvent`	once the response is hydrated	+ endpoint, duration, response size, hydration stats
`QueryFailedEvent`	when sending or hydrating fails, before rethrow	as available at the failure, + `$exception`

All of them extend QueryEvent, which holds the trace (a GraphqlQueryTrace). They are dispatched under their own class name: a listener of QueryEvent itself is never called, so register one method for each event, or one method typed QueryEvent several times, e.g. #[AsEventListener(event: QueryExecutedEvent::class)] and #[AsEventListener(event: QueryFailedEvent::class)]. The trace->id is shared by the events of a same query, e.g. to match the start and the end of a tracing span.

php

use GraphqlOrm\Event\QueryExecutedEvent;
use GraphqlOrm\Event\QueryFailedEvent;
use Symfony\Component\EventDispatcher\Attribute\AsEventListener;

final readonly class GraphqlMetricsListener
{
    public function __construct(private MetricsClient $metrics) // your own metrics client
    {
    }

    #[AsEventListener]
    public function onExecuted(QueryExecutedEvent $event): void
    {
        $this->metrics->timing('graphql.query', $event->trace->duration, ['endpoint' => $event->trace->endpoint]);
    }

    #[AsEventListener]
    public function onFailed(QueryFailedEvent $event): void
    {
        $this->metrics->increment('graphql.failure', ['exception' => $event->exception::class]);
    }
}

The events are read-only: the query cannot be changed from a listener. Query values are masked in the trace, as in the logs, unless redact_query_values is disabled (see logging), so that a listener exporting it does not leak personal data.

Events ​

Events