How to propagate Trace id to mongodb and get the tracing details while reading from collection

[sulthans]

I am using Java agent version - 2.8.0, with the below environment set I am seeing traces in jaeger UI for the DB insert with collection names.
OTEL_INSTRUMENTATION_MONGO_ENABLED=true;

This collection is reading from different scheduler application, is it possible to get the same trace context ?
I have added this env variable both applications - OTEL_PROPAGATORS=tracecontext, baggage but new trace is generated whenever app trying to read from DB.

[laurit]

This is the expected, trace context is not persisted in mongodb.

[trask]

@sulthans you may be interested to follow #11940 (I'm not sure how to put a "comment" into a mongodb query, but maybe there's a way)

[laurit]

There is no built-in support for adding parent span id to logs.
It might make things easier if you could change your ask a bit, perhaps instead the parent you want to log the id of the local root span or remote parent span?

[sulthans]

@laurit Thank you. How to log remote parent span in spring-boot? Currently i am working with Java Agent auto instrumentation
Shall i use extension or do we have other options, please suggest.

[trask]

hi @sulthans, just curious why you need the log's parent span's parent span?

[sulthans]

Hi @trask we have a application with multiple operations for a message received and the message may sent to another applications. When we search by traceId it will bring all operations/requests for the traceId now we are planning to log parent span id along with traceId for the application specific operations and requests like apply one more filter with parent span id.
I am trying with extension example - DemoPropagatorProvider and DemoPropagator but the Autoservice is not loading, whether this help to add parent span id in context ?

DemoPropagator.java

@Override public <C> Context extract(Context context, C carrier, TextMapGetter<C> getter) { String traceParentValue = getter.get(carrier, TRACEPARENT_HEADER); System.out.printf("%d TraceParentValue from headers %n", traceParentValue); if (traceParentValue != null) { Matcher matcher = TRACEPARENT_PATTERN.matcher(traceParentValue); if (matcher.matches()) { String parentSpanId = matcher.group(1); System.out.printf("%d TraceParentValue after pattern applied %n", parentSpanId); return context.with(PARENT_SPAN_ID, parentSpanId); } } return context; }

[trask]

you can already log the log's parent span id

it's only the log's parent span's parent span id that you can't log

[sulthans]

@trask I am not clear with log's parent span's parent span id, did you mean log's parent span id for local root span, log's parent span's parent span id for remote parent span

OTEL Exported json has remote parent span id.

Initial trace has parent span id - 051581bf3cb55c13

{ "name": "hello", "context": { "trace_id": "5b8aa5a2d2c872e8321cf37308d69df2", "span_id": "051581bf3cb55c13" }, "parent_id": null, "start_time": "2022-04-29T18:52:58.114201Z", "end_time": "2022-04-29T18:52:58.114687Z", "attributes": { "http.route": "some_route1" } }

Here for new operation new span and parent span id and the same set in parent_id - 051581bf3cb55c13 cannot log ?

{ "name": "hello-greetings", "context": { "trace_id": "5b8aa5a2d2c872e8321cf37308d69df2", "span_id": "5fb397be34d26b51" }, "parent_id": "051581bf3cb55c13", "start_time": "2022-04-29T18:52:58.114304Z", "end_time": "2022-04-29T22:52:58.114561Z", "attributes": { "http.route": "some_route2" } }

Please confirm, Thank you.

[trask]

OTEL Exported json has remote parent span id.

this is not true for logs, because logs aren't spans, so span_id on logs is really the log's parent span id

[sulthans]

Thanks @trask