(Delphi ActiveX) POP3 GMail XOAUTH2 Authentication

Demonstrates using OAuth2 authentication with pop.gmail.com.

Note: This example requires Chilkat v9.5.0.83 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
mailman: TChilkatMailMan;
jsonToken: TChilkatJsonObject;
success: Integer;
numEmails: Integer;

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

mailman := TChilkatMailMan.Create(Self);

mailman.MailHost := 'pop.gmail.com';
mailman.MailPort := 995;
mailman.PopSsl := 1;

mailman.PopUsername := 'my_account@gmail.com';

// If using OAuth2 authentication, leave the password empty.
mailman.PopPassword := '';

// Load our previously obtained OAuth2 access token.
// See Getting a GMail POP3 OAuth2 Access Token
jsonToken := TChilkatJsonObject.Create(Self);
success := jsonToken.LoadFile('qa_data/tokens/gmail_pop3.json');
if (success = 0) then
  begin
    Memo1.Lines.Add(jsonToken.LastErrorText);
    Exit;
  end;

mailman.OAuth2AccessToken := jsonToken.StringOf('access_token');

// Make the TLS connection to the POP3 server.
success := mailman.Pop3Connect();
if (success <> 1) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

// Authenticate..
success := mailman.Pop3Authenticate();
if (success <> 1) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

// Find out how many emails are on the server..
numEmails := mailman.CheckMail();
if (numEmails < 0) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

// Examine the POP3 session log:
Memo1.Lines.Add(mailman.Pop3SessionLog);

// The POP3 session log will look something like this:

// **** Connected to pop.gmail.com:995
// < +OK Gpop ready for requests from 87.9.200.42 l16mb86351205iok
// > AUTH XOAUTH2 dXNlcj1....VaMDJFAQE=
// < +OK Welcome.
// > STAT
// < +OK 301 1627357
// 
// -- Finished.

// End the POP3 session and close the connection to the GMail server.
success := mailman.Pop3EndSession();
if (success <> 1) then
  begin
    Memo1.Lines.Add(mailman.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('-- Finished.');
end;