(Node.js) Decode Microsoft Graph ID Token

Demonstrates how to decode a Microsoft Graph ID token.

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // In a previous example, we obtained a Microsoft Graph OAuth2 access token.
    // This example loads the JSON saved from the previous example and decodes the id_token.

    // Our Microsoft Graph OAuth2 token looks like this:

    // {
    //   "token_type": "Bearer",
    //   "scope": "openid profile User.ReadWrite Mail.ReadWrite Mail.Send Files.ReadWrite User.Read Calendars.ReadWrite Group.ReadWrite.All",
    //   "expires_in": 3600,
    //   "ext_expires_in": 3600,
    //   "access_token": "EwCQA8l6...0HhMKYwC",
    //   "refresh_token": "MCWulIvzi2yD0S...igEFn51mqcByhZtAJg",
    //   "id_token": "eyJ0eXAiOiJKV1...Q7lRDaR-7A",
    //   "expires_on": "1562862714"
    // }

    var jsonToken = new chilkat.JsonObject();
    var success = jsonToken.LoadFile("qa_data/tokens/microsoftGraph.json");
    if (success == false) {
        console.log("Failed to load the JSON file...");
        return;
    }

    // Use Chilkat's JWT API to examine the id_token..
    var jwt = new chilkat.Jwt();
    var idToken = jsonToken.StringOf("id_token");

    // Extract the JOSE header..
    var jose = jwt.GetHeader(idToken);

    var jsonHeader = new chilkat.JsonObject();
    jsonHeader.Load(jose);
    jsonHeader.EmitCompact = false;
    console.log(jsonHeader.Emit());

    // The JOSE header looks like this:

    // {
    //   "typ": "JWT",
    //   "alg": "RS256",
    //   "kid": "1LTMzakihiRla_8z2BEJVXeWMqo"
    // }

    var claims = jwt.GetPayload(idToken);

    var jsonClaims = new chilkat.JsonObject();
    jsonClaims.Load(claims);
    jsonClaims.EmitCompact = false;
    console.log(jsonClaims.Emit());

    // The claims look like this:

    // {
    //   "ver": "2.0",
    //   "iss": "https://login.microsoftonline.com/9188040d-6c67-4c5b-b112-36a304b66dad/v2.0",
    //   "sub": "AAAAAAAAAAAAAAAAAAAAAHJFryd6Gydo-XtTd1nhUNQ",
    //   "aud": "18c456bd-db75-43fe-9724-9e5d821c68ff",
    //   "exp": 1562945513,
    //   "iat": 1562858813,
    //   "nbf": 1562858813,
    //   "name": "Matt Chilkat",
    //   "preferred_username": "matt@example.com",
    //   "oid": "00000000-0000-0000-3a33-fceb9b74cc15",
    //   "tid": "9188040d-6c67-4c5b-b112-36a304b66dad",
    //   "aio": "DfibJqKnWC1c0FS6G ... W6pvTrQuYzyq16ghY$"
    // }
    // 

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    // Get each of the claims..
    var ver = jsonClaims.StringOf("ver");
    var iss = jsonClaims.StringOf("iss");
    var s_sub = jsonClaims.StringOf("sub");
    var aud = jsonClaims.StringOf("aud");
    var exp = jsonClaims.IntOf("exp");
    var iat = jsonClaims.IntOf("iat");
    var nbf = jsonClaims.IntOf("nbf");
    var name = jsonClaims.StringOf("name");
    var preferred_username = jsonClaims.StringOf("preferred_username");
    var oid = jsonClaims.StringOf("oid");
    var tid = jsonClaims.StringOf("tid");
    var aio = jsonClaims.StringOf("aio");

}

chilkatExample();