add sync handler

Author: Ankcorn

CHANGELOG.md

@@ -5,6 +5,12 @@ 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/).
 
+
+## [0.1.12] 2023-06-28
+
+- publish via CI
+- Fix: auto-loader paths
+
 ## [0.1.11] 2023-07-22
 
 - publish via CI

README.md

@@ -162,7 +162,7 @@ app.setDefaultFunctionProps({
 1. Add the baselime-node layer - `arn:aws:lambda:${region:097948374213:layer:baselime-node:3`
 2. Add the baselime-extension layer - `arn:aws:lambda:${region}:097948374213:layer:baselime-extension-${'x86_64' || 'arm64'}:1`
 3. Set the handler to `/opt/nodejs/node_modules/@baselime/lambda-node-opentelemetry/handler.handler`
-4. Set the BASELIME_ORIGINAL_HANDLER environment variable to the original path of your lambda
+4. Set the BASELIME_ACTUAL_HANDLER environment variable to the original path of your lambda
 5. Set the BASELIME_KEY environment variable with the value of your environments baselime api key
 
 ### SST

handler.cjs

@@ -1,6 +1,20 @@
 const { loadSync } = require('./loader');
+const { wrap } = require('./index');
 
-exports.handler = function (...args) {
+exports.handler = async function (...args) {
+    const actualHandler = process.env.BASELIME_ACTUAL_HANDLER;
+    const taskRoot = process.env.LAMBDA_TASK_ROOT;
 
-    loadSync();
+    if(!taskRoot) {
+        throw Error('LAMBDA_TASK_ROOT is not defined');
+    }
+
+    if(!actualHandler) {
+        throw Error('BASELIME_ACTUAL_HANDLER is not defined');
+    }
+
+    const handler = await loadSync(taskRoot, actualHandler);
+
+    const [event, context] = args
+    return wrap(handler)(event, context);
 };

handler.mjs

@@ -1,6 +1,6 @@
 {
   "name": "@baselime/lambda-node-opentelemetry",
-  "version": "0.1.11",
+  "version": "0.1.12",
   "description": "OpenTelemetry auto tracer for Node.JS based AWS Lambda functions",
   "keywords": [
     "nodejs",

handlers/handler.cjs

@@ -6,7 +6,14 @@ async function _tryImport(path:string) {
     } catch(err) {
         return false;
     }
+}
 
+function _tryRequire(path: string) {
+    try {
+        return require(path);
+    } catch(err) {
+        return false;
+    }
 }
 export async function load(taskRoot: string, originalHandler: string) {
     if (originalHandler.includes('..')) {
@@ -26,6 +33,20 @@ export async function load(taskRoot: string, originalHandler: string) {
     return lambda[functionName];
 }
 
-export function loadSync() {
-    throw Error('only esm works just now');
+export function loadSync(taskRoot: string, originalHandler: string) {
+    if (originalHandler.includes('..')) {
+        throw Error(`${originalHandler} is not a valid handler, it must not contain '..'`);
+    }
+    const pathDetails = path.parse(originalHandler);
+
+    const functionName = pathDetails.ext.slice(1);
+
+    const functionPath = path.resolve(taskRoot, pathDetails.dir, pathDetails.name);
+
+    const lambda =_tryRequire(functionPath + '.js') || _tryRequire(functionPath + '.cjs')
+
+    if (!lambda) {
+        throw Error(`Could not load ${functionPath}.js or ${functionPath}.cjs`);
+    }
+    return lambda[functionName];
 }   

loader.js

@@ -0,0 +1,10 @@
+
+
+exports.handler = function handler(e) {
+    return {
+        statusCode: 200,
+        body: JSON.stringify({
+            message: 'Hello World!',
+        })
+    }
+}

package.json

@@ -8,7 +8,6 @@ describe('load()', () => {
         const originalHandler = 'original-handler.handler';
 
         const handler = await load(taskRoot, originalHandler);
-        console.log(handler)
         expect(handler).toBeInstanceOf(Function);
 
     })