Ensure we handle the scenario the payment service code expects there to be an active span but finds none (open-telemetry#2129)

* Ensure we handle the scenario where there is currently no active span for e.g. open-telemetry#2124

* Mark this new span as active

* incorporate review comments

* revert var def change

---------

Co-authored-by: Juliano Costa <julianocosta89@outlook.com>
Co-authored-by: Pierre Tessier <pierre@pierretessier.com>

Author: 3 people

src/payment/index.js

@@ -13,7 +13,7 @@ async function chargeServiceHandler(call, callback) {
 
   try {
     const amount = call.request.amount
-    span.setAttributes({
+    span?.setAttributes({
       'app.payment.amount': parseFloat(`${amount.units}.${amount.nanos}`).toFixed(2)
     })
     logger.info({ request: call.request }, "Charge request received.")
@@ -24,9 +24,8 @@ async function chargeServiceHandler(call, callback) {
   } catch (err) {
     logger.warn({ err })
 
-    span.recordException(err)
-    span.setStatus({ code: opentelemetry.SpanStatusCode.ERROR })
-
+    span?.recordException(err)
+    span?.setStatus({ code: opentelemetry.SpanStatusCode.ERROR })
     callback(err)
   }
 }