fix: child processes run mode

src/lambda/handler-runner/child-process-runner/ChildProcessRunner.js

@@ -41,19 +41,6 @@ export default class ChildProcessRunner {
       },
     )
 
-    let message
-
-    try {
-      message = new Promise((res, rej) => {
-        childProcess.on('message', (data) => {
-          if (data.error) rej(data.error)
-          else res(data)
-        })
-      })
-    } finally {
-      childProcess.kill()
-    }
-
     childProcess.send({
       context,
       event,
@@ -63,12 +50,21 @@ export default class ChildProcessRunner {
     let result
 
     try {
-      result = await message
+      result = await new Promise((res, rej) => {
+        childProcess.on('message', (data) => {
+          if (data.error) {
+            rej(data.error)
+            return
+          }
+          res(data)
+        })
+      })
     } catch (err) {
       // TODO
       log.error(err)
-
       throw err
+    } finally {
+      childProcess.kill()
     }
 
     return result

tests/lambda-run-mode/child-processes/instances/in-process-instances.test.js

@@ -0,0 +1,37 @@
+import assert from 'node:assert'
+import { dirname, resolve } from 'node:path'
+import { fileURLToPath } from 'node:url'
+import { setup, teardown } from '../../../_testHelpers/index.js'
+import { BASE_URL } from '../../../config.js'
+
+const __dirname = dirname(fileURLToPath(import.meta.url))
+
+describe('run mode with child processes', function desc() {
+  beforeEach(() =>
+    setup({
+      servicePath: resolve(__dirname),
+    }),
+  )
+
+  afterEach(() => teardown())
+
+  it('should create a new lambda instance', async () => {
+    const url = new URL('/dev/foo', BASE_URL)
+
+    const responses = await Promise.all(
+      Array.from(Array(10).keys()).map(() => fetch(url)),
+    )
+
+    responses.forEach((response) => {
+      assert.equal(response.status, 200)
+    })
+
+    const jsons = await Promise.all(
+      responses.map((response) => response.json()),
+    )
+
+    jsons.forEach((json) => {
+      assert.deepEqual(json, 1)
+    })
+  })
+})

tests/lambda-run-mode/child-processes/instances/serverless.yml

@@ -0,0 +1,26 @@
+service: run-mode-tests
+
+configValidationMode: error
+
+plugins:
+  - ../../../../
+
+custom:
+  serverless-offline:
+    useChildProcesses: true
+
+provider:
+  memorySize: 128
+  name: aws
+  region: us-east-1 # default
+  runtime: nodejs16.x
+  stage: dev
+  versionFunctions: false
+
+functions:
+  foo:
+    events:
+      - http:
+          method: get
+          path: foo
+    handler: src/handler.foo

tests/lambda-run-mode/child-processes/instances/src/handler.js

@@ -0,0 +1,20 @@
+'use strict'
+
+const { promisify } = require('node:util')
+
+const setTimeoutPromise = promisify(setTimeout)
+
+const { stringify } = JSON
+
+let counter = 0
+
+exports.foo = async function foo() {
+  counter += 1
+
+  await setTimeoutPromise(1000, 'result')
+
+  return {
+    body: stringify(counter),
+    statusCode: 200,
+  }
+}

tests/lambda-run-mode/child-processes/instances/src/package.json

@@ -0,0 +1,3 @@
+{
+  "type": "commonjs"
+}