Delphi ActiveX Requires Chilkat v10.1.2+

Twinfield OAuth2 for Desktop App or Script

See more OAuth2 Examples

Demonstrates how to get a Twinfield OAuth2 access token from a desktop application or script. Delphi ActiveX

var
success: Integer;
oauth2: TChilkatOAuth2;
url: WideString;
numMsWaited: Integer;
json: TChilkatJsonObject;
fac: TCkFileAccess;

begin
success := 0;

//  For more information about the OAuth2, see OAuth 2.0 Authorization Flow

oauth2 := TChilkatOAuth2.Create(Self);

//  This should be the port in the localhost callback URL for your app.  
//  The callback URL would look like "http://localhost:3017/" if the port number is 3017.
oauth2.ListenPort := 3017;

oauth2.AuthorizationEndpoint := 'https://login.twinfield.com/auth/authentication/connect/authorize';
oauth2.TokenEndpoint := 'https://login.twinfield.com/auth/authentication/connect/token';

//  Replace these with actual values.
oauth2.ClientId := 'CLIENT_ID';
oauth2.ClientSecret := 'CLIENT_SECRET';

oauth2.Scope := 'openid twf.user twf.organisation twf.organisationUser offline_access';

oauth2.CodeChallenge := 1;
oauth2.CodeChallengeMethod := 'S256';

//  Twinfield requires that the request to exchange the authorization code for a token must be a GET.
//  (In most cases, OAuth2 is implemented where the exchange for token HTTP request is a POST.)
//  Note: The exchange-for-token happens within Chilkat in a background thread.  After the user interactively 
//  accepts or denies authorization, the browser receives the response and redirects to localhost:<port>,
//  where Chilkat is waiting on a background thread to receive the redirect, process it, and then send the HTTP request
//  to exchange the code for a token.  This happens internally while your code below is waiting for the authorization..)
oauth2.UncommonOptions := 'EXCHANGE_CODE_FOR_TOKEN_USING_GET';

//  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;

Memo1.Lines.Add('url = ' + url);

//  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);

//  Get the full JSON response:
json := TChilkatJsonObject.Create(Self);
json.Load(oauth2.AccessTokenResponse);
json.EmitCompact := 0;

//  The JSON response looks like this:

Memo1.Lines.Add(json.Emit());

//  Save the JSON to a file for future requests.
fac := TCkFileAccess.Create(Self);
fac.WriteEntireTextFile('qa_data/tokens/twinfield.json',json.Emit(),'utf-8',0);