(Delphi ActiveX) GeoOp OAuth2 Authorisation Code Grant (Public App)

See more OAuth2 Examples

Note: This example requires Chilkat v10.1.2 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
oauth2: TChilkatOAuth2;
url: WideString;
success: Integer;
numMsWaited: Integer;
fac: TCkFileAccess;

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

oauth2 := TChilkatOAuth2.Create(Self);

// This should match the Site URL configured for your GeoOp (non-Server) Application, such as "http://localhost:3017/"
oauth2.ListenPort := 3017;

oauth2.AuthorizationEndpoint := 'https://login.geoop.com/oauth2/code';
oauth2.TokenEndpoint := 'https://login.geoop.com/oauth2/token';

// Replace the client ID with an actual value.
oauth2.ClientId := 'GEOOP-APPLICATION-ID';
// The ClientSecret should remain empty for a GeoOp public application
oauth2.ClientSecret := '';

// We need a few special settings for GeoOp
oauth2.Scope := 'default';
oauth2.CodeChallenge := 0;
// Setting LocalHost equal to "none" prevents the "redirect_uri" query param from being sent in the initial HTTP request.
// Note: The GeoOp Application should still have a redirect URL specified as "http://localhost:3017/", where the port
// number matches the ListenPort above.
oauth2.LocalHost := 'none';

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
url := oauth2.StartAuth();
if (oauth2.LastMethodSuccess <> 1) then
  begin
    Memo1.Lines.Add(oauth2.LastErrorText);
    Exit;
  end;

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success := oauth2.LaunchBrowser(url);
if (success = 0) then
  begin
    Memo1.Lines.Add(oauth2.LastErrorText);
    Exit;
  end;

// Wait for the user to approve or deny authorization in the browser.
numMsWaited := 0;
while (numMsWaited < 90000) and (oauth2.AuthFlowState < 3) do
  begin
    oauth2.SleepMs(100);
    numMsWaited := numMsWaited + 100;
  end;

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response – The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (oauth2.AuthFlowState < 3) then
  begin
    oauth2.Cancel();
    Memo1.Lines.Add('No response from the browser!');
    Exit;
  end;

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (oauth2.AuthFlowState = 5) then
  begin
    Memo1.Lines.Add('OAuth2 failed to complete.');
    Memo1.Lines.Add(oauth2.FailureInfo);
    Exit;
  end;

if (oauth2.AuthFlowState = 4) then
  begin
    Memo1.Lines.Add('OAuth2 authorization was denied.');
    Memo1.Lines.Add(oauth2.AccessTokenResponse);
    Exit;
  end;

if (oauth2.AuthFlowState <> 3) then
  begin
    Memo1.Lines.Add('Unexpected AuthFlowState:' + IntToStr(oauth2.AuthFlowState));
    Exit;
  end;
Memo1.Lines.Add('OAuth2 authorization granted!');
Memo1.Lines.Add('Access Token = ' + oauth2.AccessToken);

// Save the entire JSON response, which includes the access token, for future calls.
// The JSON AccessTokenResponse looks like this:
// {"access_token":"e6dqdG....mzjpT04w==","token_type":"Bearer","expires_in":2592000,"owner_id":984236}

fac := TCkFileAccess.Create(Self);
fac.WriteEntireTextFile('qa_data/tokens/geoop.json',oauth2.AccessTokenResponse,'utf-8',0);

Memo1.Lines.Add('Success.');
end;