(Delphi ActiveX) GeoOp Exchange Refresh Token for New Access Token

Demonstrates how to use the /oauth2/token endpoint to exchange it for a new access token once the current access token has expired.

Note: This example requires Chilkat v9.5.0.65 or greater.

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

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
jsonToken: TChilkatJsonObject;
success: Integer;
rest: TChilkatRest;
bAutoReconnect: Integer;
responseBody: WideString;
json: TChilkatJsonObject;

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

// This example also assumes that OAuth2 access and refresh tokens were previously fetched.
// and saved in a JSON file.  

// First get our previously obtained refresh token.
// { .... "refresh_token":"e6dqdG....mzjpT04w==", .... }
jsonToken := TChilkatJsonObject.Create(Self);
success := jsonToken.LoadFile('qa_data/tokens/geoop.json');

rest := TChilkatRest.Create(Self);

// Connect to GeoOp...
bAutoReconnect := 1;
success := rest.Connect('login.geoop.com',443,1,bAutoReconnect);
if (success <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// Set the X-Version header.
rest.AddHeader('X-Version','1.0');

// Provide the required form params to get the new access token
Memo1.Lines.Add('refresh_token = ' + jsonToken.StringOf('refresh_token'));
rest.AddQueryParam('refresh_token',jsonToken.StringOf('refresh_token'));
rest.AddQueryParam('grant_type','refresh_token');
rest.AddQueryParam('client_id','GEOOP-CLIENT-ID');
rest.AddQueryParam('client_secret','GEOOP-CLIENT-SECRET');

responseBody := rest.FullRequestFormUrlEncoded('POST','/oauth2/token');
if (rest.LastMethodSuccess <> 1) then
  begin
    Memo1.Lines.Add(rest.LastErrorText);
    Exit;
  end;

// If the response status code did not indicate success, then see what happened..
if (rest.ResponseStatusCode <> 200) then
  begin
    Memo1.Lines.Add('Request Header: ');
    Memo1.Lines.Add(rest.LastRequestHeader);
    Memo1.Lines.Add('----');
    Memo1.Lines.Add('Response StatusCode = ' + IntToStr(rest.ResponseStatusCode));
    Memo1.Lines.Add('Response StatusLine: ' + rest.ResponseStatusText);
    Memo1.Lines.Add('Response Header:');
    Memo1.Lines.Add(rest.ResponseHeader);
    Memo1.Lines.Add(responseBody);
    Exit;
  end;

json := TChilkatJsonObject.Create(Self);
json.EmitCompact := 0;
json.Load(responseBody);

// Show the full JSON response.  It should contain the new access token...
Memo1.Lines.Add(json.Emit());
end;