(Android™) Refresh HMRC OAuth2 Access Token

Demonstrates how to refresh an HMRC access token.

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.

    // See Get HMRC Access Token 
    // for sample code showing how to obtain a HMRC access token for desktop apps.

    // It is assumed we previously obtained an OAuth2 access token for HMRC.

    CkJsonObject jsonToken = new CkJsonObject();
    boolean success = jsonToken.LoadFile("qa_data/tokens/hmrc.json");
    if (success != true) {
        Log.i(TAG, "Failed to load hmrc.json");
        return;
        }

    // The access token JSON looks something like this:

    // {
    //   "token_type": "Bearer",
    //   "scope": "user_impersonation",
    //   "expires_in": "3599",
    //   "ext_expires_in": "0",
    //   "expires_on": "1524783438",
    //   "not_before": "1524779538",
    //   "resource": "https://mydomain.api.crm.dynamics.com",
    //   "access_token": "...",
    //   "refresh_token": "...",
    //   "id_token": "..."
    // }

    CkOAuth2 oauth2 = new CkOAuth2();

    oauth2.put_TokenEndpoint("https://test-api.service.hmrc.gov.uk/oauth/token");

    // Replace these with actual values.
    oauth2.put_ClientId("HMRC-CLIENT-ID");
    oauth2.put_ClientSecret("HMRC-CLIENT-SECRET");

    // Get the "refresh_token"
    oauth2.put_RefreshToken(jsonToken.stringOf("refresh_token"));

    // Send the HTTP POST to refresh the access token..
    success = oauth2.RefreshAccessToken();
    if (success != true) {
        Log.i(TAG, oauth2.lastErrorText());
        return;
        }

    // Load the access token response into the json object 
    jsonToken.Load(oauth2.accessTokenResponse());

    // If an "expires_on" member does not exist, then add the JSON member by
    // getting the current system date/time and adding the "expires_in" seconds.
    // This way we'll know when the token expires.
    if (jsonToken.HasMember("expires_on") == false) {
        CkDateTime dtExpire = new CkDateTime();
        dtExpire.SetFromCurrentSystemTime();
        dtExpire.AddSeconds(jsonToken.IntOf("expires_in"));
        jsonToken.AppendString("expires_on",dtExpire.getAsUnixTimeStr(false));
        }

    // Save the new JSON access token response to a file.
    // The access + refresh tokens contained in this JSON will be needed for the next refresh.
    CkStringBuilder sbJson = new CkStringBuilder();
    jsonToken.put_EmitCompact(false);
    jsonToken.EmitSb(sbJson);
    sbJson.WriteFile("qa_data/tokens/hmrc.json","utf-8",false);

    Log.i(TAG, "OAuth2 authorization granted!");
    Log.i(TAG, "New Access Token = " + oauth2.accessToken());

  }

  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."
  }
}