Java

Refresh HMRC OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to refresh an HMRC access token. Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  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();
    success = jsonToken.LoadFile("qa_data/tokens/hmrc.json");
    if (success != true) {
        System.out.println("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) {
        System.out.println(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);

    System.out.println("OAuth2 authorization granted!");
    System.out.println("New Access Token = " + oauth2.accessToken());
  }
}