From 99e271a559d01a59cdda32c11e3a6582e0e04c49 Mon Sep 17 00:00:00 2001
From: cesare soldini <smilemachine@gmail.com>
Date: Wed, 21 Oct 2020 19:45:13 +0200
Subject: [PATCH 1/2] fix(error message): change error message to display stack
 and more information (#1459)

---
 src/utils/serve-functions.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/utils/serve-functions.js b/src/utils/serve-functions.js
index 97f4c37f546..8fd4f3c22e1 100644
--- a/src/utils/serve-functions.js
+++ b/src/utils/serve-functions.js
@@ -20,11 +20,15 @@ const { detectFunctionsBuilder } = require('./detect-functions-builder')
 const { getFunctions } = require('./get-functions')
 const { NETLIFYDEVLOG, NETLIFYDEVWARN, NETLIFYDEVERR } = require('./logo')
 
+const formatJsError = (err) => `${err.name}: ${err.message}\n\t${err.stack.join('\n\t')}`
+const formatLambdaLocalError = (err) => `${err.errorType}: ${err.errorMessage}\n\t${err.stackTrace.join('\n\t')}`
+
 const handleErr = function (err, response) {
   response.statusCode = 500
-  response.write(`${NETLIFYDEVERR} Function invocation failed: ${err.toString()}`)
+  const errorString = err instanceof Error ? formatJsError(err) : formatLambdaLocalError(err)
+  response.write(`Function invocation failed: ${errorString}`)
   response.end()
-  console.log(`${NETLIFYDEVERR} Error during invocation:`, err)
+  console.log(`${NETLIFYDEVERR} Function invocation failed:`, errorString)
 }
 
 const formatLambdaError = (err) => chalk.red(`${err.errorType}: ${err.errorMessage}`)

From 7033257e0be7508c9f0c4f0ce7d7ecedab7dab2c Mon Sep 17 00:00:00 2001
From: erezrokah <erezrokah@users.noreply.github.com>
Date: Tue, 10 Nov 2020 17:36:55 +0100
Subject: [PATCH 2/2] fix(command-dev): improve functions error reporting and
 logging

---
 src/utils/serve-functions.js | 43 ++++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 19 deletions(-)

diff --git a/src/utils/serve-functions.js b/src/utils/serve-functions.js
index 8fd4f3c22e1..ea8be6328fc 100644
--- a/src/utils/serve-functions.js
+++ b/src/utils/serve-functions.js
@@ -20,15 +20,12 @@ const { detectFunctionsBuilder } = require('./detect-functions-builder')
 const { getFunctions } = require('./get-functions')
 const { NETLIFYDEVLOG, NETLIFYDEVWARN, NETLIFYDEVERR } = require('./logo')
 
-const formatJsError = (err) => `${err.name}: ${err.message}\n\t${err.stack.join('\n\t')}`
-const formatLambdaLocalError = (err) => `${err.errorType}: ${err.errorMessage}\n\t${err.stackTrace.join('\n\t')}`
+const formatLambdaLocalError = (err) => `${err.errorType}: ${err.errorMessage}\n  ${err.stackTrace.join('\n  ')}`
 
 const handleErr = function (err, response) {
   response.statusCode = 500
-  const errorString = err instanceof Error ? formatJsError(err) : formatLambdaLocalError(err)
-  response.write(`Function invocation failed: ${errorString}`)
-  response.end()
-  console.log(`${NETLIFYDEVERR} Function invocation failed:`, errorString)
+  const errorString = typeof err === 'string' ? err : formatLambdaLocalError(err)
+  response.end(errorString)
 }
 
 const formatLambdaError = (err) => chalk.red(`${err.errorType}: ${err.errorMessage}`)
@@ -39,24 +36,32 @@ const capitalize = function (t) {
   return t.replace(/(^\w|\s\w)/g, (string) => string.toUpperCase())
 }
 
+const validateLambdaResponse = (lambdaResponse) => {
+  if (lambdaResponse === undefined) {
+    return { error: 'lambda response was undefined. check your function code again' }
+  }
+  if (!Number(lambdaResponse.statusCode)) {
+    return {
+      error: `Your function response must have a numerical statusCode. You gave: $ ${lambdaResponse.statusCode}`,
+    }
+  }
+  if (lambdaResponse.body && typeof lambdaResponse.body !== 'string') {
+    return { error: `Your function response must have a string body. You gave: ${lambdaResponse.body}` }
+  }
+
+  return {}
+}
+
 const createSynchronousFunctionCallback = function (response) {
   return function callbackHandler(err, lambdaResponse) {
     if (err) {
       return handleErr(err, response)
     }
-    if (lambdaResponse === undefined) {
-      return handleErr('lambda response was undefined. check your function code again.', response)
-    }
-    if (!Number(lambdaResponse.statusCode)) {
-      console.log(
-        `${NETLIFYDEVERR} Your function response must have a numerical statusCode. You gave: $`,
-        lambdaResponse.statusCode,
-      )
-      return handleErr('Incorrect function response statusCode', response)
-    }
-    if (lambdaResponse.body && typeof lambdaResponse.body !== 'string') {
-      console.log(`${NETLIFYDEVERR} Your function response must have a string body. You gave:`, lambdaResponse.body)
-      return handleErr('Incorrect function response body', response)
+
+    const { error } = validateLambdaResponse(lambdaResponse)
+    if (error) {
+      console.log(`${NETLIFYDEVERR} ${error}`)
+      return handleErr(error, response)
     }
 
     response.statusCode = lambdaResponse.statusCode