How to plot a span attribute in Jaeger data source

Grafana
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1

I have a question about retrieving an attribute in Grafana from Jaeger.

The java code (simplified) that produces the span is as following:

Span span = tracer.spanBuilder(“sinewave”).startSpan();
Thread.sleep((long) (20 + rnd.nextDouble()50));
sineValue = Math.sin(new Date().getTime() * Math.PI2 / 1000 / 7); // every 7 seconds
span.setAttribute(“value”, sineValue);
span.end();

I’m successful in saving the traces in Jaeger and ElasticSearch using Otel collector.

Using ElasticSearch source i had no problem in plotting the “value” field extracted from the span, where I see the sinewave.

However using the Jaeger source, the only plottable value is the duration of the segment.

The value is even there, once inspecting the Jaeger query, the information is there:

traceID:“e0159cd5ac88fc7721eaf931256168cb”
spans:Array[1]
0:Object
traceID:“e0159cd5ac88fc7721eaf931256168cb”
spanID:“7be2236a5b0b2e43”
operationName:“coswave”
references:Array[0]
startTime:1678911821187524
duration:46972
tags:Array[4]
0:Object
1:Object
2:Object
3:Object
key:“value”
type:“float64”
value:-0.03351019606799947

The value does not make it to the “Data” panel. The only fields are TraceID, Trace Name, StartTime and Duration.

Can anyone tell how can I use the Jaeger source to plot the “value” tag, and not just the duration of the span?

Thank you,
Razvan