Allow span to be passed to helpers

Not every instrumentation makes the spans that they're working
with into active spans for the current context. Additionally,
some instrumentations provide hooks where the relevant span is
provided as an argument, but is not the active span.

To account for these scenarios, the helpers now take an optional
span argument as their final argument (except for sendError, which
always creates a new span)

src/helpers.ts

@@ -1,8 +1,10 @@
-import { SpanStatusCode, AttributeValue, trace } from "@opentelemetry/api"
+import { trace, SpanStatusCode } from "@opentelemetry/api"
 import { Client } from "./client"
 
-function setAttribute(attribute: string, value: AttributeValue) {
-  const activeSpan = trace.getActiveSpan()
+import type { Span, AttributeValue } from "@opentelemetry/api"
+
+function setAttribute(attribute: string, value: AttributeValue, span?: Span) {
+  const activeSpan = span ?? trace.getActiveSpan()
   if (activeSpan) {
     activeSpan.setAttribute(attribute, value)
   } else {
@@ -32,66 +34,67 @@ function circularReplacer() {
   }
 }
 
-function setSerialisedAttribute(attribute: string, value: any) {
+function setSerialisedAttribute(attribute: string, value: any, span?: Span) {
   const serialisedValue = JSON.stringify(value, circularReplacer())
   if (serialisedValue) {
-    setAttribute(attribute, serialisedValue)
+    setAttribute(attribute, serialisedValue, span)
   }
 }
 
 function setPrefixedAttribute(
   prefix: string,
   suffix: string,
-  value: AttributeValue
+  value: AttributeValue,
+  span?: Span
 ) {
   if (suffix) {
-    setAttribute(`${prefix}.${suffix}`, value)
+    setAttribute(`${prefix}.${suffix}`, value, span)
   }
 }
 
-export function setParams(params: any) {
-  setSerialisedAttribute("appsignal.request.parameters", params)
+export function setParams(params: any, span?: Span) {
+  setSerialisedAttribute("appsignal.request.parameters", params, span)
 }
 
-export function setSessionData(sessionData: any) {
-  setSerialisedAttribute("appsignal.request.session_data", sessionData)
+export function setSessionData(sessionData: any, span?: Span) {
+  setSerialisedAttribute("appsignal.request.session_data", sessionData, span)
 }
 
-export function setCustomData(customData: any) {
-  setSerialisedAttribute("appsignal.custom_data", customData)
+export function setCustomData(customData: any, span?: Span) {
+  setSerialisedAttribute("appsignal.custom_data", customData, span)
 }
 
-export function setTag(tag: string, value: AttributeValue) {
-  setPrefixedAttribute("appsignal.tag", tag, value)
+export function setTag(tag: string, value: AttributeValue, span?: Span) {
+  setPrefixedAttribute("appsignal.tag", tag, value, span)
 }
 
-export function setHeader(header: string, value: AttributeValue) {
-  setPrefixedAttribute("appsignal.request.headers", header, value)
+export function setHeader(header: string, value: AttributeValue, span?: Span) {
+  setPrefixedAttribute("appsignal.request.headers", header, value, span)
 }
 
-export function setName(name: string) {
-  setAttribute("appsignal.name", name)
+export function setName(name: string, span?: Span) {
+  setAttribute("appsignal.name", name, span)
 }
 
-export function setCategory(category: string) {
-  setAttribute("appsignal.category", category)
+export function setCategory(category: string, span?: Span) {
+  setAttribute("appsignal.category", category, span)
 }
 
-export function setBody(body: string) {
-  setAttribute("appsignal.body", body)
+export function setBody(body: string, span?: Span) {
+  setAttribute("appsignal.body", body, span)
 }
 
-export function setNamespace(namespace: string) {
-  setAttribute("appsignal.namespace", namespace)
+export function setNamespace(namespace: string, span?: Span) {
+  setAttribute("appsignal.namespace", namespace, span)
 }
 
-export function setRootName(name: string) {
-  setAttribute("appsignal.root_name", name)
+export function setRootName(name: string, span?: Span) {
+  setAttribute("appsignal.root_name", name, span)
 }
 
-export function setError(error: Error) {
+export function setError(error: Error, span?: Span) {
   if (error && error.name && error.message) {
-    const activeSpan = trace.getActiveSpan()
+    const activeSpan = span ?? trace.getActiveSpan()
     if (activeSpan) {
       activeSpan.recordException(error)
       activeSpan.setStatus({