fix callback support

Author: Ankcorn

CHANGELOG.md

@@ -5,6 +5,9 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## [0.1.18] 2023-07-24
+
+- Improved robustness of callback support
 
 ## [0.1.17] 2023-07-24
 

examples/serverless/serverless.yml

@@ -27,6 +27,7 @@ provider:
           Resource: '*'
   tags:
     'baselime:tracing': true
+    'baselime:version': 5
 functions:
   hello:
     handler: src/main.handler

examples/serverless/src/dispatcher.js

@@ -1,8 +1,8 @@
 
-exports.handler = async (event, context) => {
+exports.handler = (event, context, callback) => {
     context.callbackWaitForEmptyEventLoop = false;
-    console.log(event.Records[0].Sns)
-    return {
+    console.log(event.Records[0].Sns);
+    return callback(null, {
       message: 'req processed'
-    }
+    })
 };

multiRegion.json

@@ -1,7 +1,7 @@
 {
     "regions": [
-        "eu-west-1",
         "eu-west-2",
+        "eu-west-1",
         "us-east-1",
         "us-east-2",
         "us-west-2",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@baselime/lambda-node-opentelemetry",
-  "version": "0.1.17",
+  "version": "0.1.18",
   "description": "OpenTelemetry auto tracer for Node.JS based AWS Lambda functions",
   "keywords": [
     "nodejs",

src/index.ts

@@ -37,7 +37,6 @@ export function wrap(handler: Handler) {
       attributes: flatten({
         event,
         context: {
-          callbackWaitsForEmptyEventLoop: lambda_context.callbackWaitsForEmptyEventLoop,
           functionName: lambda_context.functionName,
           functionVersion: lambda_context.functionVersion,
           invokedFunctionArn: lambda_context.invokedFunctionArn,
@@ -67,10 +66,7 @@ export function wrap(handler: Handler) {
     const ctx = trace.setSpan(context.active(), span);
 
     try {
-      // if (callback && handler.constructor.name !== "AsyncFunction" && handler.length === 3) {
-      //   console.log("promisify handler");
-      //   handler = promisify(handler);
-      // }
+
       const result = await context.with(ctx, async (e, lc, cb) => {
         const unkownResult = handler(e, lc, (err, res) => {
           if (err) {
@@ -80,20 +76,21 @@ export function wrap(handler: Handler) {
           }
 
           if (res) {
-            span.setAttributes(({ result: res }) as Attributes);
+            span.setAttributes(flatten({ result: res }));
           }
           if (cb) {
-            cb(err, res)
+            span.end();
+            cb(err, res);
           }
-          span.end();
         });
-
         if (unkownResult) {
           return await unkownResult
         }
       }, null, event, lambda_context, callback);
+      if (result) {
+        span.setAttributes(flatten({ result }));
+      }
 
-      span.setAttributes(({ result }) as Attributes);
       span.end();
       return result;
     } catch (e) {