Pascal (Lazarus/Delphi)

Get a Xero OAuth2 Access Token

See more OAuth2 Examples

Gets a Xero OAuth2 access token. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.OAuth2,
  Chilkat.StringBuilder;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  oauth2: TOAuth2;
  url: string;
  numMsWaited: Integer;
  sbJson: TStringBuilder;

begin
  success := False;

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

  oauth2 := TOAuth2.Create;

  //  For Xero OAuth2, set the listen port equal to the port used
  //  in the Authorized Redirect URL for the Client ID.
  //  For example, in this case the Authorized Redirect URL would be http://localhost:55568/
  //  Your app should choose a port not likely not used by any other application.
  //  See Xero OAuth2 for Desktop Apps for more information.
  oauth2.ListenPort := 55568;

  oauth2.AuthorizationEndpoint := 'https://login.xero.com/identity/connect/authorize';
  oauth2.TokenEndpoint := 'https://identity.xero.com/connect/token';

  //  Replace these with actual values.
  oauth2.ClientId := 'XERO_APP_OAUTH2_CLIENT_ID';
  oauth2.ClientSecret := 'XERO_APP_OAUTH2_CLIENT_SECRET';
  oauth2.UseBasicAuth := True;

  //  See https://developer.xero.com/documentation/oauth2/scopes for a complete list of scopes.
  //  You will need to change the scopes depending on what access is needed..
  oauth2.Scope := 'openid profile email accounting.transactions accounting.attachments accounting.settings payroll.employees offline_access';

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

  WriteLn('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 = False) then
    begin
      WriteLn(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();
      WriteLn('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
      WriteLn('OAuth2 failed to complete.');
      WriteLn(oauth2.FailureInfo);
      Exit;
    end;

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

  if (oauth2.AuthFlowState <> 3) then
    begin
      WriteLn('Unexpected AuthFlowState:' + oauth2.AuthFlowState);
      Exit;
    end;

  //  Save the full JSON access token response to a file.
  sbJson := TStringBuilder.Create;
  sbJson.Append(oauth2.AccessTokenResponse);
  sbJson.WriteFile('qa_data/tokens/xero-access-token.json','utf-8',False);

  //  The saved JSON response looks like this:

  //  	{
  //  	 "access_token": "...",
  //  	 "token_type": "Bearer",
  //  	 "expires_in": 3600,
  //  	 "refresh_token": "..."
  //  	}
  //  
  WriteLn('OAuth2 authorization granted!');
  WriteLn('Access Token = ' + oauth2.AccessToken);


  oauth2.Free;
  sbJson.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.