How to generate random SHA1 hash to use as ID in node.js?

Question

I am using this line to generate a sha1 id for node.js:

crypto.createHash(\'sha1\').digest(\'hex\');

The problem is that it\'s returning th

Answer 1

Do it in the browser, too !

EDIT: this didn't really fit into the flow of my previous answer. I'm leaving it here as a second answer for people that might be looking to do this in the browser.

You can do this client side in modern browsers, if you'd like

// str byteToHex(uint8 byte)
//   converts a single byte to a hex string 
function byteToHex(byte) {
  return ('0' + byte.toString(16)).slice(-2);
}

// str generateId(int len);
//   len - must be an even number (default: 40)
function generateId(len = 40) {
  var arr = new Uint8Array(len / 2);
  window.crypto.getRandomValues(arr);
  return Array.from(arr, byteToHex).join("");
}

console.log(generateId())
// "1e6ef8d5c851a3b5c5ad78f96dd086e4a77da800"

console.log(generateId(20))
// "d2180620d8f781178840"

Browser requirements

Browser    Minimum Version
--------------------------
Chrome     11.0
Firefox    21.0
IE         11.0
Opera      15.0
Safari     5.1