(Node.js) Get Access Token using a Pre-Created JSON Web Token

Demonstrates how to get an access token using a pre-created JSON Web Token (JWT).

For more information, see https://developer.abnamro.com/get-started#headingFive

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.

    // We're going to duplicate this CURL statement:
    // curl -X POST https://api-sandbox.abnamro.com/v1/oauth/token \
    // -H "Content-Type: application/x-www-form-urlencoded" \
    // -H "API-Key: xxxxxx" \
    // -d 'client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer&grant_type=client_credentials&client_assertion=eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ4eHh4eHgiLCJleHAiOiIxNDk5OTQ3NjY4IiwiaXNzIjoibWUiLCJhdWQiOiJodHRwczovL2F1dGgtc2FuZGJveC5hYm5hbXJvLmNvbS9vYXV0aC90b2tlbiJ9.jGwHKG_YjgKpR8NPpaLu6nJ97obeP2vcxg6fOWBKdJ0&scope=tikkie'

    // Load our pre-creaed private key PEM file.
    // Note: Please share your public key along with your app name and developer email id at api.support@nl.abnamro.com. 
    // Token generation will not work unless public key is associated with your app.
    var privkey = new chilkat.PrivateKey();

    var success = privkey.LoadPemFile("qa_data/pem/abnAmroPrivateKey.pem");
    if (success == false) {
        console.log(privkey.LastErrorText);
        return;
    }

    // Create the JWT.
    var jwt = new chilkat.Jwt();

    // Create the header:
    // {
    //     "typ": "JWT",
    //     "alg": "RS256"
    // }
    var jsonHeader = new chilkat.JsonObject();
    jsonHeader.UpdateString("typ","JWT");
    jsonHeader.UpdateString("alg","RS256");

    // Create the payload:
    // {
    //     "nbf": 1499947668,
    //     "exp": 1499948668,
    //     "iss": "me",
    //     "sub": "anApiKey",
    //     "aud": "https://auth-sandbox.abnamro.com/oauth/token"
    // }
    var jsonPayload = new chilkat.JsonObject();

    var curDateTime = jwt.GenNumericDate(0);

    // Set the "not process before" timestamp to now.
    success = jsonPayload.AddIntAt(-1,"nbf",curDateTime);

    // Set the timestamp defining an expiration time (end time) for the token
    // to be now + 1 hour (3600 seconds)
    success = jsonPayload.AddIntAt(-1,"exp",curDateTime+3600);

    jsonPayload.UpdateString("iss","me");
    jsonPayload.UpdateString("sub","anApiKey");
    jsonPayload.UpdateString("aud","https://auth-sandbox.abnamro.com/oauth/token");

    // Produce the smallest possible JWT:
    jwt.AutoCompact = true;

    var jwtStr = jwt.CreateJwtPk(jsonHeader.Emit(),jsonPayload.Emit(),privkey);
    if (jwt.LastMethodSuccess !== true) {
        console.log(jwt.LastErrorText);
        return;
    }

    var http = new chilkat.Http();

    var req = new chilkat.HttpRequest();
    req.AddParam("client_assertion_type","urn:ietf:params:oauth:client-assertion-type:jwt-bearer");
    req.AddParam("grant_type","client_credentials");
    req.AddParam("client_assertion",jwtStr);
    req.AddParam("scope","tikkie");

    // resp: HttpResponse
    var resp = http.PostUrlEncoded("https://api-sandbox.abnamro.com/v1/oauth/token",req);
    if (http.LastMethodSuccess == false) {
        console.log(http.LastErrorText);
        return;
    }

    if (resp.StatusCode !== 200) {
        console.log(resp.BodyStr);

        return;
    }

    // Get the JSON result:
    // {
    //     "access_token": "{your access token}",
    //     "expires_in": "{duration of validity in seconds}",
    //     "scope": "{scope(s) for which the access token is valid}",
    //     "token_type": "{it is always Bearer}"
    // }
    var json = new chilkat.JsonObject();
    json.Load(resp.BodyStr);
    console.log("access_token: " + json.StringOf("access_token"));
    console.log("token_type: " + json.StringOf("token_type"));
    console.log("expires_in: " + json.StringOf("expires_in"));
    console.log("scope: " + json.StringOf("scope"));


}

chilkatExample();