Custom exporters

Implement the contract:

use Cbox\Telemetry\Contracts\Exporter;
use Cbox\Telemetry\Support\{ExportResult, Signal, SignalSet, TelemetryBatch};

final class ClickhouseExporter implements Exporter
{
    public function name(): string
    {
        return 'clickhouse';
    }

    public function supports(): SignalSet
    {
        return SignalSet::of(Signal::Traces, Signal::Events);
    }

    public function export(TelemetryBatch $batch): ExportResult
    {
        try {
            $this->client->insert('spans', $this->rows($batch->spans));

            return ExportResult::ok();
        } catch (ConnectionException $e) {
            return ExportResult::retryable($e->getMessage());
        } catch (Throwable $e) {
            return ExportResult::failed($e->getMessage());
        }
    }
}

Register it by class name in config — it resolves through the container:

'exporters' => [ClickhouseExporter::class, 'otlp'],

Rules of the pipeline

• You only receive signals you declared in supports(); the batch is pre-filtered.
• Never throw — classify failures in the ExportResult:
  • ok() — accepted.
  • partial($rejected, $reason) — accepted, some items rejected.
  • retryable($reason, $retryAfterSeconds) — transient (429/503, timeouts). The pipeline/scheduler decides on retries.
  • failed($reason) — permanent; retrying won't help.
• Exports run at terminate (after the response) — but they still block the worker. Keep timeouts tight.
• $batch->resource carries the service attributes; include them in your output so multi-service backends can distinguish sources.