nodejs the string parsing and conversion base64

nodejs atob not supported and btoa base64 string conversion, the conversion method is as follows:

// Switch to Base64 
var strToBase64 = new new Buffer ( 'aaabbbccc') toString ( 'Base64'. );
 // Base64 string of anti-analytic 
var base64ToStr = new new Buffer (STR, 'Base64') toString ().;