simple login function using PDO

[junkomatic]

Hi, im still in the early learning stages, banging my head against walls looking for clues. Iv been reading the manual to no avail.

 

im building a user log in system based on the phpAcadamy tutorial 'Register & Login'. They use mysql_connect in the tutorial, but I am using a PDO connection to mysql.

 

1) the function user_id_from_username should return the `user_id` entry for the posted $username. mine does not, im confused about how to simply return the entry, and i just need a little bit of guidance and explanation.

 

2) the login function works, BUT i need it to return $user_id if TRUE, so that i can set the session.

 

here is my code:

function user_id_from_username(PDO $db, $username) {
	$stmt = $db->prepare('SELECT `user_id` FROM `users` WHERE `username` = 1');
	$stmt->bindParam(1, $username);
	$stmt->execute();
	return ($stmt->fetchColumn());
}				//??? I NEED THIS FUNCTION TO RETURN THE `user_id` ENTRY FOR $username

function login(PDO $db, $username, $password) {
	$user_id = user_id_from_username($db, $username);
	$password = md5($password);
	
	$stmt = $db->prepare('SELECT COUNT(`user_id`) FROM `users` WHERE `username` = ? AND `password` = ?');
	$stmt->bindParam(1, $username);
	$stmt->bindParam(2, $password);
	$stmt->execute();
	return (bool) $stmt->fetchColumn();
}				//??? I NEED THIS FUNCTION TO RETURN $user_id IF TRUE (to set session)

//---------------------login.php-----------------------

if (empty($_POST) === false) {
	$username = $_POST['username'];
	$password = $_POST['password'];
	
	if (empty($username) === true || empty($password) === true) {
		$errors[] = 'You need to enter a username and password.';
	} else if (user_exists($db, $username) === false) {
		$errors[] = 'We can\'t find that username. Have you registered?';
	} else if (user_active($db, $username) === false) {
		$errors[] = 'You haven\'t activated your account!';
	} else {
		$login = login($db, $username, $password);
		if ($login === false) {
			$errors[] = 'That username/password combination is incorrect.';
		} else {
		die($login);


		} 
	}
	
	print_r($errors);
}

So, according to this login script, after a successful login (good username and password, and active account) it should output the $user_id integer:  "die($login)". 

 

It prints the error array correctly, it logs in ok, except for this next step.

Thanks in advance!

[junkomatic]

(I didnt include the other two functions: user_exists and user_active, because i have them working properly)

[junkomatic]

and i just noticed in line 2 that '1' should be '?'.

 

but still, the problem has to do with the return lines missing something critical, i think.

[junkomatic]

ok i fixed it:

function login(PDO $db, $username, $password) {
	$user_id = user_id_from_username($db, $username);
	$password = md5($password);
	
	$stmt = $db->prepare('SELECT COUNT(`user_id`) FROM `users` WHERE `username` = ? AND `password` = ?');
	$stmt->bindParam(1, $username);
	$stmt->bindParam(2, $password);
	$stmt->execute();
	if($stmt->fetchColumn() > 0) {
		return $user_id;
	} else { 
		return FALSE;
}
}

just needed to add the if/else at the end of this login function duh!