Working with folders in Node

The Node.js fs core module provides many handy methods you can use to work with folders.

Use fs.access() to check if the folder exists and Node can access it with its permissions.

Use fs.mkdir() or fs.mkdirSync() to create a new folder.

const fs = require('fs')

const folderName = '/Users/flavio/test'

try {
  if (!fs.existsSync(dir)){
    fs.mkdirSync(dir)
  }
} catch (err) {
  console.error(err)
}

Use fs.readdir() or fs.readdirSync to read the contents of a directory.

This piece of code reads the content of a folder, both files and subfolders, and returns their relative path:

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

const folderPath = '/Users/flavio'

fs.readdirSync(folderPath)

You can get the full path:

fs.readdirSync(folderPath).map(fileName => {
  return path.join(folderPath, fileName)
}

You can also filter the results to only return the files, and exclude the folders:

const isFile = fileName => {
  return fs.lstatSync(fileName).isFile()
}

fs.readdirSync(folderPath).map(fileName => {
  return path.join(folderPath, fileName)
}).filter(isFile)

Use fs.rename() or fs.renameSync() to rename folder. The first parameter is the current path, the second the new path:

const fs = require('fs')

fs.rename('/Users/flavio', '/Users/roger', err => {
  if (err) {
    console.error(err)
    return
  }
  //done
})

fs.renameSync() is the synchronous version:

const fs = require('fs')

try {
  fs.renameSync('/Users/flavio', '/Users/roger')
} catch (err) {
  console.error(err)
}

Use fs.rmdir() or fs.rmdirSync() to remove a folder.

Removing a folder that has content can be more complicated than you need.

In this case I recommend installing the fs-extra module, which is very popular and well maintained, and it's a drop-in replacement of the fs module, providing more features on top of it.

In this case the remove() method is what you want.

Install it using

npm install fs-extra

and use it like this:

const fs = require('fs-extra')

const folder = '/Users/flavio'

fs.remove(folder, err => {
  console.error(err)
})

It can also be used with promises:

fs.remove(folder).then(() => {
  //done
}).catch(err => {
  console.error(err)
})

or with async/await:

async function removeFolder(folder) {
  try {
    await fs.remove(folder)
    //done
  } catch (err) {
    console.error(err)
  }
}

const folder = '/Users/flavio'
removeFolder(folder)