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PHP Extension

POP3 GMail XOAUTH2 Authentication

See more GMail SMTP/IMAP/POP Examples

Demonstrates using OAuth2 authentication with pop.gmail.com.

Note: This example requires Chilkat v9.5.0.83 or greater.

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PHP Extension
<?php

include("chilkat.php");

$success = false;

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

$mailman = new CkMailMan();

$mailman->put_MailHost('pop.gmail.com');
$mailman->put_MailPort(995);
$mailman->put_PopSsl(true);

$mailman->put_PopUsername('my_account@gmail.com');

// If using OAuth2 authentication, leave the password empty.
$mailman->put_PopPassword('');

// Load our previously obtained OAuth2 access token.
// See Getting a GMail POP3 OAuth2 Access Token
$jsonToken = new CkJsonObject();
$success = $jsonToken->LoadFile('qa_data/tokens/gmail_pop3.json');
if ($success == false) {
    print $jsonToken->lastErrorText() . "\n";
    exit;
}

$mailman->put_OAuth2AccessToken($jsonToken->stringOf('access_token'));

// Make the TLS connection to the POP3 server.
$success = $mailman->Pop3Connect();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Authenticate..
$success = $mailman->Pop3Authenticate();
if ($success != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Find out how many emails are on the server..
$numEmails = $mailman->CheckMail();
if ($numEmails < 0) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

// Examine the POP3 session log:
print $mailman->pop3SessionLog() . "\n";

// 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 != true) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

print '-- Finished.' . "\n";

?>