How convert a string to type Uint8Array in nodejs

You can use Buffer.from(string[, encoding]). The Buffer class has implemented the Uint8Array interface in Node since v4.x. You can also optionally specify an encoding with which to do string processing in both directions, i.e. buffer.toString([encoding]).

Uint8Array.from(text.split('').map(letter => letter.charCodeAt(0)));

or (appears about 18% faster):

Uint8Array.from(Array.from(text).map(letter => letter.charCodeAt(0)));

Note: These only work for ASCII, so all the letters are modulo 256, so if you try with Russian text, it won't work.

Why not simply using:

const resEncodedMessage = new TextEncoder().encode(message)

This is how I do it when grabbing a string

   var myString = "[4,12,43]"
   var stringToArray = myString.replace('[', '').replace(']', '').split(',');
   var stringToIntArray = Uint8Array.from(stringToArray );
   console.log(stringToIntArray);