OpenTelemetry

span.set_attribute("openlayer.session.id", session_id)
span.set_attribute("openlayer.user.id", user_id)

span.setAttribute("openlayer.session.id", sessionId);
span.setAttribute("openlayer.user.id", userId);

from opentelemetry import baggage, context
from opentelemetry.processor.baggage import BaggageSpanProcessor

# When configuring your TracerProvider (pip install opentelemetry-processor-baggage):
provider.add_span_processor(
    BaggageSpanProcessor(lambda key: key.startswith("openlayer."))
)

# At the session boundary, set the IDs once:
ctx = baggage.set_baggage("openlayer.session.id", session_id)
ctx = baggage.set_baggage("openlayer.user.id", user_id, context=ctx)
token = context.attach(ctx)
try:
    ...  # every span created here carries the session and user
finally:
    context.detach(token)

import { context, propagation } from "@opentelemetry/api";
import { BaggageSpanProcessor } from "@opentelemetry/baggage-span-processor";

// When configuring your provider (npm install @opentelemetry/baggage-span-processor):
new BaggageSpanProcessor((key) => key.startsWith("openlayer."));

// At the session boundary, set the IDs once:
const bag = propagation.createBaggage({
  "openlayer.session.id": { value: sessionId },
  "openlayer.user.id": { value: userId },
});
context.with(propagation.setBaggage(context.active(), bag), () => {
  // every span created here carries the session and user
});