node module version conflict when installing modul

问题:

I'm trying to make an Electron application (https://electron.atom.io/) that reads data from my serial port. I'm new to web technologies in general, I know some javascript, but I'm a c++ guy.

So I pulled in their quick-start from github, ran

npm install && npm start

With this easily working I tried to install and run serialport with

npm install serialport

With that installed and running fine with a test file, I tried to combine the two and put require('serialport') in the index.html file. With this in there I get this error:

Uncaught Error: The module '/home/user/Documents/Programing/Git/Arduino-mpu6050/electron-quick-start/node_modules/serialport/build/Release/serialport.node'
was compiled against a different Node.js version using
NODE_MODULE_VERSION 51. This version of Node.js requires
NODE_MODULE_VERSION 53. Please try re-compiling or re-installing
the module (for instance, using `npm rebuild` or`npm install`).
    at process.module.(anonymous function) [as dlopen] (ELECTRON_ASAR.js:173:20)
    at Object.Module._extensions..node (module.js:598:18)
    at Object.module.(anonymous function) [as .node] (ELECTRON_ASAR.js:173:20)
    at Module.load (module.js:488:32)
    at tryModuleLoad (module.js:447:12)
    at Function.Module._load (module.js:439:3)
    at Module.require (module.js:498:17)
    at require (internal/module.js:20:19)
    at bindings (/home/user/Documents/Programing/Git/Arduino-mpu6050/electron-quick-start/node_modules/bindings/bindings.js:76:44)
    at Object.<anonymous> (/home/user/Documents/Programing/Git/Arduino-mpu6050/electron-quick-start/node_modules/serialport/lib/bindings.js:3:35)

Any ideas how to fix it? I'm not using two different versions of Node, why am I getting this error.

System OS info:

Distributor ID: Ubuntu
Description:    Ubuntu 16.04.2 LTS
Release:    16.04
Codename:   xenial

回答1:

When this type of version mismatch occurs, you can either choose an electron distribution with the target Node version or rebuild the npm package. Since Electron's distribution has skipped Node v7.0.0 which is configured with NODE_MODULE_VERSION 51 (and jumped to v7.4.0), you would have to rebuild the serialport package.

In your app's directory (where package.json is located at),

1. Install electron-rebuild

npm install --save-dev electron-rebuild

2. Rebuild

./node_modules/.bin/electron-rebuild

Or, even a better option - set environment variables from the first place.

# Electron's version.
export npm_config_target=1.6.1
# The architecture of Electron, can be ia32 or x64.
export npm_config_arch=x64
export npm_config_target_arch=x64
# Download headers for Electron.
export npm_config_disturl=https://atom.io/download/electron
# Tell node-pre-gyp that we are building for Electron.
export npm_config_runtime=electron
# Tell node-pre-gyp to build module from source code.
export npm_config_build_from_source=true
# Install all dependencies, and store cache to ~/.electron-gyp.
HOME=~/.electron-gyp npm install

Take a look at the Electron's documentation page for using native Node modules. https://electron.atom.io/docs/tutorial/using-native-node-modules/

回答2:

electron-rebuild on postinstall.

Depending on what you're doing, you can use electron-rebuild to rebuild serialport to the version of electron you have installed.

To do so:

npm install --save-dev electron-rebuild

$(npm bin)/electron-rebuild                 # Mac and Linux.

.\node_modules\.bin\electron-rebuild.cmd    # Windows.

Because I kept forgetting to do this after doing an npm install (and to help others that downloaded the project), I added the following two scripts to package.json:

"scripts": {
  "start": "electron .",

  "postinstall": "electron-rebuild",    
  "electron-rebuild": "electron-rebuild"
},

The postinstall will automatically run after doing a npm install so after the typical install finishes you'll see a console log message with electron-rebuild and it will automatically rebuild serialport, and any other native library you have, to the electron version. This means that you shouldn't even have to think about running electron-rebuild going forward.