dyld: Symbol not found: _napi_module_register

Question

Had my node working with the VS Code debugger last night no problem. I haven't touched anything besides install the npm mysql package.

I come back tonight and its throwing this error:

Debugger listening on [::]:49952
dyld: lazy symbol binding failed: Symbol not found: _napi_module_register
  Referenced from: /Users/adamsawyers/node_modules/bufferutil/prebuilds/darwin- 
 x64/node-napi.node
  Expected in: flat namespace
dyld: Symbol not found: _napi_module_register
  Referenced from: /Users/myusername/node_modules/bufferutil/prebuilds/darwin- 
 x64/node-napi.node
  Expected in: flat namespace

Apparently my installation of n (a node version handling package in npm) is busted somehow. My research told me that napi_module_register is part of the n package, but I'm not sure how this got messed up especially since I had it working last night.

I tried reinstalling my node packages, reinstalling n, rebuilding the project file structure, even restarting my computer. Nothing has worked so far.

Any suggestions?

Answer 1

Apparently VS code doesn't like v6.10.3 of nodejs which I am running to create lambda functions in AWS (that is the version specified by AWS)

I use the N package to manage my node version. After switching to the latest version 10.7.0 as of 07/25/2018 (command: sudo n latest) and rerunning the debugger in VS code, it worked perfectly

I'm still unsure as the the cause, but hopefully others find this solution helpful

Answer 2

This exact error happened to me because:

1. I needed socket.io to run on Node
   • Which in turn needs ws (websockets on Node)
2. Also, I needed to run this on an outdated Node version (Node 7) for a very good reason (believe me, I would not want to do this if I wouldn't have to)
3. However, trying to use it on that old version causes above error message.

Solution

This is a terrible solution, but at least I got it to work.

After some researching, I found no good solution to this. However, a close look at the source code shows that there is a fallback.js next to index.js which implements the same functionality as the native build but without needing a build. This will probably slow things down significantly, but at least it works:

1. yarn add module-alias
2. prefix your actual code with this (eg via node -r fallbacks.js ):

// fallbacks.js
const moduleAlias = require('module-alias');

const dependencyRoot = getDependencyRoot(); // whatever is your root folder, maybe __dirname + '..'

moduleAlias.addAlias('bufferutil', dependencyRoot + '/node_modules/bufferutil/fallback.js');
moduleAlias.addAlias('utf-8-validate', dependencyRoot + '/node_modules/utf-8-validate/fallback.js');


// run actual code here...

PS: In my case, in order to allow ws to run on Node 7, I also had to babel it, since its using modern synytax.