Create an object from a base64 encoded input JSON string in Node.js

nodejs_base64.js

const inputStr = ... ; // a base64 encoded string

if (inputStr) {
  const decodedStr = Buffer.from(inputStr, 'base64').toString('utf8');
  const result = JSON.parse(decodedStr);
  if (result) {
    // ...
  }
}