[Open Telemetry] - How to Wrap/Decorate Span and Log Exporters in Quarkus?

[cleidiano]

Context

We need to wrap (not replace) resolved exporters to apply cross-cutting concerns (PII masking, compliance filtering) before export.

In vanilla OTel this is done via AutoConfigurationCustomizerProvider:

builder.addSpanExporterCustomizer((exporter, config) -> new PiiMaskingWrapper(exporter));
builder.addLogRecordExporterCustomizer((exporter, config) -> new PiiLogWrapper(exporter));
builder.addMetricExporterCustomizer((exporter, config) -> new PiiMetricWrapper(exporter));

For metrics, this SPI works perfectly in Quarkus, the customizer receives the resolved MetricExporter and wrapping works as expected.

For spans and logs, it doesn't. Quarkus registers the entire SpanProcessor/LogRecordProcessor infrastructure internally without giving the SPI customizer a chance to touch the created SpanExporter/LogRecordExporter. By the time addSpanExporterCustomizer/addLogRecordExporterCustomizer callbacks could run, the exporters are already wired into processors that Quarkus controls.

Current Workaround

For spans and logs, we rebuild the entire OTLP exporter from scratch in a CDI producer, coupling to VertxGrpcSender, VertxHttpSender, GrpcExporter, HttpExporter, and other internal APIs, just to wrap the result. This duplicates config handling and breaks on upgrades.

Question

Is there a recommended/support way to wrap SpanExporter and LogRecordExporter in Quarkus?

1. Is there an existing mechanism we're missing?
2. Could the span/log processor setup be adjusted to honor addSpanExporterCustomizer/addLogRecordExporterCustomizer the same way metrics already does?

Environment: Quarkus 3.31.3 · OTel SDK 1.55+ · Java 21

[cescoffier]

/CC @brunobat

[brunobat]

This is something that I think we can done for tracing. For logs, I'll need to take a deeper look.
This PR can help with this on the tracing side: #52752
I will work on that soon.

[cleidiano]

Thank you so much for taking a look into this! I'll check out PR #52752 for the tracing side