Login a user in a typo3 extenbase extension

gistfile1.txt

<?php

// now login the user
$fe_user = $GLOBALS['TSFE']->fe_user;
$fe_user->createUserSession(array('uid' => $uid));
$fe_user->user = $fe_user->getRawUserByUid($uid);
$fe_user->fetchGroupData();
$GLOBALS['TSFE']->loginUser = 1;

// set the cookie
$reflection = new \ReflectionClass($GLOBALS['TSFE']->fe_user);
$setSessionCookieMethod = $reflection->getMethod('setSessionCookie');
$setSessionCookieMethod->setAccessible(TRUE);
$setSessionCookieMethod->invoke($GLOBALS['TSFE']->fe_user);

?>