(Android™) ABN AMRO Create Signed JSON Web Token

Demonstrates how to create a signed JWT to be used for authenticating requests to the ABN AMRO REST API's.

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

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

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

    // Create public/private key pair (RSA)
    CkRsa rsa = new CkRsa();

    // Generate a 2048-bit key.
    boolean success = rsa.GenerateKey(2048);
    if (success != true) {
        Log.i(TAG, rsa.lastErrorText());
        return;
        }

    // Export the key to PEM files.
    // Write one PEM file for the private key, and one for the public key.
    CkPrivateKey privkey = rsa.ExportPrivateKeyObj();
    success = privkey.SavePemFile("qa_data/pem/abnAmroPrivateKey.pem");

    CkPublicKey pubkey = rsa.ExportPublicKeyObj();
    success = pubkey.SavePemFile(true,"qa_data/pem/abnAmroPublicKey.pem");
    // 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.

    // Create the JWT.
    CkJwt jwt = new CkJwt();

    // Create the header:
    // {
    //     "typ": "JWT",
    //     "alg": "RS256"
    // }
    CkJsonObject jsonHeader = new CkJsonObject();
    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"
    // }
    CkJsonObject jsonPayload = new CkJsonObject();

    int 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.put_AutoCompact(true);

    String jwtStr = jwt.createJwtPk(jsonHeader.emit(),jsonPayload.emit(),privkey);
    if (jwt.get_LastMethodSuccess() != true) {
        Log.i(TAG, jwt.lastErrorText());
        return;
        }

    // Here is the JWT:
    Log.i(TAG, jwtStr);

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}