biobulkbende.org/node_modules/fs-extra/docs/outputFile.md

outputFile(file, data, [options, callback])

Almost the same as writeFile (i.e. it overwrites), except that if the parent directory does not exist, it's created. file must be a file path (a buffer or a file descriptor is not allowed). options are what you'd pass to fs.writeFile().

• file <String>
• data <String> | <Buffer> | <Uint8Array>
• options <Object> | <String>
• callback <Function>

Example:

const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'
fs.outputFile(file, 'hello!', err => {
  console.log(err) // => null

  fs.readFile(file, 'utf8', (err, data) => {
    if (err) return console.error(err)
    console.log(data) // => hello!
  })
})

// With Promises:
fs.outputFile(file, 'hello!')
.then(() => fs.readFile(file, 'utf8'))
.then(data => {
  console.log(data) // => hello!
})
.catch(err => {
  console.error(err)
})