The best way to run npm install for nested folders

问题:

What is the most correct way to install npm packages in nested sub folders?

my-app
  /my-sub-module
  package.json
package.json

What is the best way to have packages in /my-sub-module be installed automatically when npm install run in my-app?

回答1:

If you want to run a single command to install npm packages in nested subfolders, you can run a script via npm and main package.json in your root directory. The script will visit every subdirectory and run npm install.

Below is a .js script that will achieve the desired result:

var fs = require('fs')
var resolve = require('path').resolve
var join = require('path').join
var cp = require('child_process')
var os = require('os')

// get library path
var lib = resolve(__dirname, '../lib/')

fs.readdirSync(lib)
  .forEach(function (mod) {
    var modPath = join(lib, mod)
// ensure path has package.json
if (!fs.existsSync(join(modPath, 'package.json'))) return

// npm binary based on OS
var npmCmd = os.platform().startsWith('win') ? 'npm.cmd' : 'npm'

// install folder
cp.spawn(npmCmd, ['i'], { env: process.env, cwd: modPath, stdio: 'inherit' })
})

Note that this is an example taken from a StrongLoop article that specifically addresses a modular node.js project structure (including nested components and package.json files).

As suggested, you could also achieve the same thing with a bash script.

EDIT: Made the code work in Windows

回答2:

I prefer using post-install, if you know the names of the nested subdir. In package.json:

"scripts": {
  "postinstall": "cd nested_dir && npm install",
  ...
}

回答3:

My solution is very similar. Pure Node.js

The following script examines all subfolders (recursively) as long as they have package.json and runs npm install in each of them. One can add exceptions to it: folders allowed not having package.json. In the example below one such folder is "packages". One can run it as a "preinstall" script.

const path = require('path')
const fs = require('fs')
const child_process = require('child_process')

const root = process.cwd()
npm_install_recursive(root)

// Since this script is intended to be run as a "preinstall" command,
// it will do `npm install` automatically inside the root folder in the end.
console.log('===================================================================')
console.log(`Performing "npm install" inside root folder`)
console.log('===================================================================')

// Recurses into a folder
function npm_install_recursive(folder)
{
    const has_package_json = fs.existsSync(path.join(folder, 'package.json'))

    // Abort if there's no `package.json` in this folder and it's not a "packages" folder
    if (!has_package_json && path.basename(folder) !== 'packages')
    {
        return
    }

    // If there is `package.json` in this folder then perform `npm install`.
    //
    // Since this script is intended to be run as a "preinstall" command,
    // skip the root folder, because it will be `npm install`ed in the end.
    // Hence the `folder !== root` condition.
    //
    if (has_package_json && folder !== root)
    {
        console.log('===================================================================')
        console.log(`Performing "npm install" inside ${folder === root ? 'root folder' : './' + path.relative(root, folder)}`)
        console.log('===================================================================')

        npm_install(folder)
    }

    // Recurse into subfolders
    for (let subfolder of subfolders(folder))
    {
        npm_install_recursive(subfolder)
    }
}

// Performs `npm install`
function npm_install(where)
{
    child_process.execSync('npm install', { cwd: where, env: process.env, stdio: 'inherit' })
}

// Lists subfolders in a folder
function subfolders(folder)
{
    return fs.readdirSync(folder)
        .filter(subfolder => fs.statSync(path.join(folder, subfolder)).isDirectory())
        .filter(subfolder => subfolder !== 'node_modules' && subfolder[0] !== '.')
        .map(subfolder => path.join(folder, subfolder))
}

回答4:

Adding Windows support to snozza's answer

var fs = require('fs')
var resolve = require('path').resolve
var join = require('path').join
var cp = require('child_process')

// get library path
var lib = resolve(__dirname, '../lib/')

fs.readdirSync(lib)
  .forEach(function (mod) {
    var modPath = join(lib, mod)
    // ensure path has package.json
    if (!fs.existsSync(join(modPath, 'package.json'))) return

    // Determine OS and set command accordingly
    const cmd = /^win/.test(process.platform) ? 'npm.cmd' : 'npm';

    // install folder
    cp.spawn(cmd, ['i'], { env: process.env, cwd: modPath, stdio: 'inherit' })
})

回答5:

Just for reference in case people come across this question. You can now:

• Add a package.json to a subfolder
• Install this subfolder as reference-link in the main package.json:

npm install --save path/to/my/subfolder