parseJWT.js
Decode the payload from a JSON Web Token (JWT).
Example
// The JWT
let token = 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c';
// The payload
/*
{
"sub": "1234567890",
"name": "John Doe",
"iat": 1516239022
}
*/
let payload = parseJWT(token);
The helper function
/**
* Decode a JWT payload
* https://stackoverflow.com/a/38552302
* @param {String} token The JWT
* @return {Object} The decoded payload
*/
function parseJWT (token) {
let base64Url = token.split('.')[1];
let base64 = base64Url.replace(/-/g, '+').replace(/_/g, '/');
let jsonPayload = decodeURIComponent(atob(base64).split('').map(function(c) {
return '%' + ('00' + c.charCodeAt(0).toString(16)).slice(-2);
}).join(''));
return JSON.parse(jsonPayload);
}