(Delphi DLL) Rabobank Refresh OAuth2 Access Token

Demonstrates how to refresh an expired Rabobank OAuth2 access token. (No interactive user interaction is required to refresh an access token.)

For more information, see https://developer.rabobank.nl/implementoauth2

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Http, HttpRequest, HttpResponse, JsonObject, FileAccess;

...

procedure TForm1.Button1Click(Sender: TObject);
var
json: HCkJsonObject;
success: Boolean;
req: HCkHttpRequest;
http: HCkHttp;
resp: HCkHttpResponse;
fac: HCkFileAccess;

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

// We previously obtained an access token and saved the JSON to a file using this example:
// Get Rabobank OAuth2 Access Token

json := CkJsonObject_Create();
success := CkJsonObject_LoadFile(json,'qa_data/tokens/rabobank.json');
if (success <> True) then
  begin
    Exit;
  end;

// {
//   "token_type": "Bearer",
//   "access_token": "AAIkYTU0ZWM ... sxE0KL0HHWw",
//   "expires_in": 3600,
//   "consented_on": 1584641121,
//   "scope": "ais.balances.read ais.transactions.read-90days ais.transactions.read-history",
//   "refresh_token": "AAJXXSdN ... Uiblz9ILkxNBlytRGA",
//   "refresh_token_expires_in": 157784760,
//   "expires_on": "1584644722"
// }

// Refresh the access token by sending a POST like this:
// 

// POST /oauth2/token
// Headers:
//     Content-Type: application/x-www-form-urlencoded
//     Authorization: Basic BASE64(CLIENT_ID + ":" + CLIENT_SECRET)
// 
// Body (x-www-form-urlencoded):
//     grant_type: refresh_token
//     refresh_token: REFRESH_TOKEN

req := CkHttpRequest_Create();
CkHttpRequest_AddParam(req,'grant_type','refresh_token');
CkHttpRequest_AddParam(req,'refresh_token',CkJsonObject__stringOf(json,'refresh_token'));

http := CkHttp_Create();

// Causes the "Authorization: Basic BASE64(CLIENT_ID + ":" + CLIENT_SECRET)" header to be added..
CkHttp_putBasicAuth(http,True);
CkHttp_putLogin(http,'YOUR_APP_CLIENT_ID');
CkHttp_putPassword(http,'YOUR_APP_CLIENT_SECRET');

resp := CkHttp_PostUrlEncoded(http,'https://api-sandbox.rabobank.nl/openapi/sandbox/oauth2/token',req);
if (CkHttp_getLastMethodSuccess(http) <> True) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

// Load the JSON response.
CkJsonObject_Load(json,CkHttpResponse__bodyStr(resp));
CkJsonObject_putEmitCompact(json,False);

// Show the JSON response.
Memo1.Lines.Add(CkJsonObject__emit(json));

Memo1.Lines.Add('Response status code: ' + IntToStr(CkHttpResponse_getStatusCode(resp)));

// If the response status code is not 200, then it's an error.
if (CkHttpResponse_getStatusCode(resp) <> 200) then
  begin
    Exit;
  end;

CkHttpResponse_Dispose(resp);

// Save the refreshed access token JSON to a file for future requests.
fac := CkFileAccess_Create();
CkFileAccess_WriteEntireTextFile(fac,'qa_data/tokens/rabobank.json',CkJsonObject__emit(json),'utf-8',False);

CkJsonObject_Dispose(json);
CkHttpRequest_Dispose(req);
CkHttp_Dispose(http);
CkFileAccess_Dispose(fac);

end;