Pascal (Lazarus/Delphi)

GMail SMTP Send using Previously Obtained OAuth2 Access Token

See more GMail SMTP/IMAP/POP Examples

Demonstrates how to send email using GMail and OAuth2 authentication. This example assumes an OAuth2 access token was previously obtained. 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.MailMan,
  Chilkat.Email,
  Chilkat.JsonObject;

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

procedure RunDemo;
var
  success: Boolean;
  json: TJsonObject;
  accessToken: string;
  mailman: TMailMan;
  email: TEmail;

begin
  success := False;

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

  //  See Get GMail SMTP Access Token 
  //  for sample code showing how to obtain a GMail SMTP access token for desktop apps.

  //  In this example, our access token was previously saved to the following file which contains JSON like this:
  //  	{
  //  	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
  //  	 "token_type": "Bearer",
  //  	 "expires_in": 3600,
  //  	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
  //  	}
  //  
  json := TJsonObject.Create;
  success := json.LoadFile('qa_data/tokens/_gmailSmtp.json');
  if (success <> True) then
    begin
      WriteLn('Failed to load GMail access token file.');
      Exit;
    end;
  accessToken := json.StringOf('access_token');

  mailman := TMailMan.Create;

  //  Set the properties for the GMail SMTP server:
  mailman.SmtpHost := 'smtp.gmail.com';
  mailman.SmtpPort := 587;
  mailman.StartTLS := True;

  //  The SMTP username should be the GMail address of the user's account that authorized your app to send email.
  mailman.SmtpUsername := 'chilkat.support@gmail.com';
  mailman.OAuth2AccessToken := accessToken;

  //  Create a new email object
  email := TEmail.Create;

  email.Subject := 'This is a test';
  email.Body := 'This is a test';
  email.From := 'Chilkat <chilkat.support@gmail.com>';
  email.AddTo('Chilkat Admin','admin@chilkatsoft.com');
  //  To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

  //  Call SendEmail to connect to the SMTP server and send.
  //  The connection (i.e. session) to the SMTP server remains
  //  open so that subsequent SendEmail calls may use the
  //  same connection.  
  success := mailman.SendEmail(email);
  if (success <> True) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  //  You may close the connection here.  If the connection is kept open, 
  //  the next call to mailman.SendEmail will continue using the already-established connection
  //  (and automatically re-connect if needed).
  success := mailman.CloseSmtpConnection();
  if (success <> True) then
    begin
      WriteLn('Connection to SMTP server not closed cleanly.');
    end;

  WriteLn('Email Sent via GMail with OAuth2 authentication.');


  json.Free;
  mailman.Free;
  email.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.