file-exists 

"file-exists": "1.0.0"

const fileExists = require('file-exists');
 
fileExists('/index.html', (err, exists) => console.log(exists)) // OUTPUTS: true or false
 
fileExists('/index.html').then(exists => {
  console.log(exists) // OUTPUTS: true or false
})
 
console.log(fileExists.sync('/index.html')) // OUTPUTS: true or false