Use Zipkin sanitizers

[pavolloffay]

The sanitizers https://github.com/jaegertracing/jaeger/tree/master/cmd/collector/app/sanitizer could be implemented as processors if we think they are optional https://github.com/open-telemetry/opentelemetry-collector#processors

[pavolloffay]

So service_name_sanitizer and utf8_sanitizer are not installed by default.

Jaeger core only uses Zipkin sanitizers, that operate on zipkin spans https://github.com/jaegertracing/jaeger/blob/master/cmd/collector/app/sanitizer/zipkin/span_sanitizer.go

[pavolloffay]

Otel collector might be doing some sanitization on zipkin spans when zipkin spans are transformed to OTEL model. We will have to test this.

[pavolloffay]

Errors

Errors are not recognized properly when for errors like span.tag("error", "error type or message")

    @RequestMapping("error_span")
    public String errorSpan() {
        zipkinTracing.tracing().tracer().newTrace()
            .start()
            .name("error_span")
            .tag("error", "some error")
            .finish();
        return "error_span_created";
    }

jaeger OTEL collector: https://i.imgur.com/PdWHkIn.png
all-in-one (with sanitizer): https://i.imgur.com/9ZjHKFt.png

Duration

Zipkin spans might have duration set to 0. In this case Jaeger derives the duration from annotations.

    @RequestMapping("missing_duration")
    public String missingDuration() {
        Span span = zipkinTracing.tracing().tracer().newTrace()
            .name("missing_duration")
            .start(0)
            .annotate("cs");
        span.annotate(zipkinTracing.tracing().clock(span.context()).currentTimeMicroseconds() + 1500, "cr");
        span.finish(0);
        return "missing_duration";
    }

Jaeger OTEL collector: https://i.imgur.com/ebs0tP5.png - the duration seems to be set correctly.
Jaeger all-in-one: https://i.imgur.com/w9FK1mz.png

[pavolloffay]

The error semantic conventions haven't been yet defined at the spec level open-telemetry/opentelemetry-specification#427, open-telemetry/opentelemetry-specification#432 and open-telemetry/opentelemetry-specification#521

Once it's done we can correctly convert zipkin errors to OTEL model. If it deviates from OT we will implement a new proper mapping in Jaeger.

[pavolloffay]

I have submitted a proposal to OTEL spec that includes behavior of zipkin sanitizers open-telemetry/opentelemetry-specification#566

[pavolloffay]

Closing as it is a "low level" issue related to V2 which might take a different approach.