一个es模块友好的简化版本的jwt-decode.js

function b64DecodeUnicode(str) {
  return decodeURIComponent(
    atob(str).replace(/(.)/g, function (m, p) {
      var code = p.charCodeAt(0).toString(16).toUpperCase();
      if (code.length < 2) {
        code = "0" + code;
      }
      return "%" + code;
    })
  );
}

function base64_url_decode(str) {
  var output = str.replace(/-/g, "+").replace(/_/g, "/");
  switch (output.length % 4) {
    case 0:
      break;
    case 2:
      output += "==";
      break;
    case 3:
      output += "=";
      break;
    default:
      throw "Illegal base64url string!";
  }

  try {
    return b64DecodeUnicode(output);
  } catch (err) {
    return atob(output);
  }
}

export function jwtDecode(token, options) {
  options = options || {};
  var pos = options.header === true ? 0 : 1;
  try {
    return JSON.parse(base64_url_decode(token.split(".")[pos]));
  } catch (e) {
    console.log(e.message);
  }
}

简单的功能与试接

const parseJwt = (token) => {
  try {
    return JSON.parse(atob(token.split('.')[1]));
  } catch (e) {
    return null;
  }
};

谢谢!

我使用这个函数来根据这个答案获得有效负载、报头、exp(过期时间)、iat(发出时间)

function parseJwt(token) {
  try {
    // Get Token Header
    const base64HeaderUrl = token.split('.')[0];
    const base64Header = base64HeaderUrl.replace('-', '+').replace('_', '/');
    const headerData = JSON.parse(window.atob(base64Header));

    // Get Token payload and date's
    const base64Url = token.split('.')[1];
    const base64 = base64Url.replace('-', '+').replace('_', '/');
    const dataJWT = JSON.parse(window.atob(base64));
    dataJWT.header = headerData;

// TODO: add expiration at check ...


    return dataJWT;
  } catch (err) {
    return false;
  }
}

const jwtDecoded = parseJwt('YOUR_TOKEN') ;
if(jwtDecoded)
{
    console.log(jwtDecoded)
}

解码JSON Web令牌(JWT)的简单NodeJS解决方案

function decodeTokenComponent(value) {
    const buff = new Buffer(value, 'base64')
    const text = buff.toString('ascii')
    return JSON.parse(text)
}

const token = 'xxxxxxxxx.XXXXXXXX.xxxxxxxx'
const [headerEncoded, payloadEncoded, signature] = token.split('.')
const [header, payload] = [headerEncoded, payloadEncoded].map(decodeTokenComponent)

console.log(`header: ${header}`)
console.log(`payload: ${payload}`)
console.log(`signature: ${signature}`)

function parseJwt(token) {
  var base64Payload = token.split('.')[1];
  var payload = Buffer.from(base64Payload, 'base64');
  return JSON.parse(payload.toString());
}

let payload= parseJwt("eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c");
console.log("payload:- ", payload);

如果使用node，你可能需要使用缓冲包:

npm install buffer
var Buffer = require('buffer/').Buffer

如果使用node.js 16或更高版本，可以使用内置的base64url编码器/解码器。

let payload = JSON.parse(Buffer.from(token.split(".")[1], "base64url"));