PHP MVC - SESSION not persistent - php

Question

I ran into a problem with my PHP session lately.
For developing I am using a MVC (Model View Controller) structure.
The important files:
├───classes
├───controllers
│ base_controller.php
| ...
│
├───helpers
├───parts
└───views
login_view.php
register_view.php
...
index.php
Problem: login_view.php can't "find" the $_SESSION["currentUser"], that is set in base_controller.php.
Explanation: The session is started in the index.php before the base_controller.php is loaded.
<?php
require_once("php/classes/DB.class.php");
require_once("php/classes/Functions.class.php");
require_once("php/classes/User.class.php");
session_start();
require_once("php/classes/ErrorMsg.class.php");
require_once("php/controllers/base_controller.php");
?>
The $_SESSION["currentUser"] is set in the base_controller.php after successful login. The $user object is stored in the Session. (No, not serialized, I know. But on purpose.)
if(login($username, $password)){
$m = "";
$_SESSION['currentUser'] = $user;
require_once('php/views/register_view.php');
exit();
}
The session is successfully created. Register_view.php is displayed and I am able to use the session.
When I reload the page however, and login_view.php is showed again, I can not use the session at all. Also, it seems that the base_controller.php itself can't use the session too.
The important parts of my base_controller.php:
$user = new User();
$error = new ErrorMsg();
...
//Button Login Pressed
if(isset($_POST["submit_login"])){
if(isset($_POST["login_username"]) && isset($_POST["login_password"])){
$username = htmlspecialchars($_POST["login_username"], ENT_QUOTES);
$password = $_POST["login_password"];
if(login($username, $password)){
$m = "";
$_SESSION['currentUser'] = $user;
require_once('php/views/register_view.php');
exit();
}
else{
$m = $error->WriteError("Login nicht möglich. Falsche Zugangsdaten.", "base_controller -> function login", "");
require_once('php/views/login_view.php');
exit();
}
}
}
...
//Does not work. isset($_SESSION["currentUser"]) returns FALSE
if(isset($_SESSION["currentUser"])){
if($_SESSION["currentUser"]->isLoggedIn()){
require_once('php/views/register_view.php');
exit();
}
}
// Display Login Page
require_once("php/views/login_view.php");
So to summarize it: register_view.php can use $_SESSION["currentUser"], login_view.php and base_controller.php cannot.
I've tried to
echo var_dump($_SESSION['currentUser']);
same as
echo var_dump($_SESSION[]);
but both return NULL or an empty array when used in login_view.php -> But give valid results in register_view.php
Do you have any idea what could be the cause of this non-persistent session?
I really hope I just made a very foolish mistake. You're welcome to laugh constructively. ^^

Answer 1

Are you calling start_session in login_view.php too?
start_session should always be called before using session variables.

Answer 2

Problem solved!
How I solved it:
Please make sure to read the original problem so you understand the fix.
The main problem was, that I tried to save the object $user directly into the $_SESSION. Due to the __PHP_Incomplete_Class the whole thing did not work. I fixed it with storing the User-Data in an array.
$_SESSION["currentUser"] = array("id"=>$user->GetUserId(),"firstname"=>$user->GetFirstname(),"lastname"=>$user->GetLastname(),"username"=>$user->GetUsername(),"lastlogin"=>$user->GetLastLogin(),"group"=>$user->GetGroup(), "class"=>$user->GetClass());
Now, the advantage of directly editing and using functions from the Class however, is gone. I can not use something like
foreach($_SESSION["currentUser"] as $key => $obj){
return '<p>'.$obj->getContent().'</p>';
}
anymore. Also, I can't directly set fields in the User Class anymore.
$_SESSION["currentUser"]->checkIfOnline();
However, to "log out" I just have to delete the session.
unset($_SESSION["currentUser"]); //To delete User session
Once all user-data is saved in a DB, it's perfect that way Session deleted = User logged out.