PHP __PHP_Incomplete_Class Object with my $_SESSION data

I've got a site setup that, on page load, turns all user submitted strings into SafeString objects. For those unfamiliar with SafeString, it basically forces the user to echo out sanitized data preventing XSS and whatnot..

Anyways, there's a problem. My $_SESSION array is being filled with __PHP_Incomplete_Class Object. From what I've read, this is due to not initializing the class before the session and then storing class objects in the session.

Here's my code:

require_once __WEBROOT__ . '/includes/safestring.class.ph开发者_运维知识库p'; 

$temp = array
(
   &$_SERVER, &$_GET, &$_POST, &$_COOKIE,
   &$_SESSION, &$_ENV, &$_REQUEST, &$_FILES,
   &$HTTP_SERVER_VARS, &$HTTP_GET_VARS,
   &$HTTP_POST_VARS, &$HTTP_COOKIE_VARS,
   &$HTTP_POST_FILES, &$HTTP_ENV_VARS
); 

function StringsToSafeString(&$array)
{
   foreach ($array as $key => $value)
   {
      if (is_string($array[$key]))
      {
         $array[$key] = new SafeString($value);
      } 

      if (is_array($array[$key]))
      {
         StringsToSafeString($array[$key]);
      }
   }
}

StringsToSafeString($temp);

unset($temp);

I can't think of a way to rewrite this which would solve the problem :/

Any ideas?

---

When you're accessing $_SESSION, you're not just changing the current script's copy of the data read from the session, you're writing SafeString objects back into the active session.

But putting custom objects in the session is dodgy and something I would generally try to avoid. To be able to do it you have to have defined the class in question before calling session_start; if you don't, PHP's session handler won't know how to deserialise the instances of that class, and you'll end up with the __PHP_Incomplete_Class Object.

So avoid frobbing the session. If you must take this approach, make a copy of the data from $_SESSION into a local $mysession array. However, I have to say I think the whole idea of a SafeString is dangerous and unworkable; I don't think this approach is ever going to be watertight. Whether a string of raw text is ‘safe’ is nothing to do with where it came from, it is a property of how you encode it for the target context.

If you get another text string from a different source such as the database, or a file, or calculated within the script itself, it needs exactly the same handling as a string that came from the user: it needs to be htmlspecialchars​ed. You're going to have to write that escape anyway; the safestring gains you nothing. If you need to send the string to a different destination format, you would need a different escape.

You cannot encapsulate all string processing problems into one handy box and never think about them again; that's just not how strings work.

---

I know it's been years since this was asked, but I'm posting my answer because none of the answers above actually explain to the OP what is actually wrong.

PHP serializes its sessions using the built-in serialize and unserialize methods. serialize of PHP has the ability to serialize PHP objects (aka class instances) and convert them to string. When you unserialize those strings, It converts them back those same classes with those values. Classes who have some private properties and want to encode/decode that or do something complex in their serialization/deserialization implement the Serializable class and add serialize and unserialize methods to the class.

When PHP's unserialize tries to unserialize a class object, but the class name isn't declared/required, instead of giving a warning or throwing an Exception, it converts it to an object of __PHP_Incomplete_Class.

If you don't want your session objects to convert to __PHP_Incomplete_Class, You can do it by either requiring the class files before you invoke session_start, or by registering an autoload function.

---

You just have to include the safestring.class.php before you call session_start() when you want to read the SafeString objects from $_SESSION variable:

<?php

require_once __WEBROOT__ . '/includes/safestring.class.php';    
session_start();

print_r($_SESSION);

and yeah, if you are using PHP framework that (most probably) calls session_start() internally, make sure you require_once the class file beforehand (use hooks or whatever mechanisms that the framework provides).

---

I solved the problem using json_encode and json_decode function.

This is where I wanted to assign the value to session.

$user_json              = json_encode($user);
$_SESSION['user']           = $user_json;

This is where I show the user after decoding the json

session_start();

$user_json= $_SESSION['user'];
$user = json_decode($user_json);

This solves my problem but I am not sure about performance or security. I haven't checked them.

---

Lukman's answer is correct. But you already mention that in your question, so apparently you can't instantiate the class before the session starts, for some reason.

You may want to check if sessions start automatically in the php config: http://www.php.net/manual/en/session.configuration.php#ini.session.auto-start

If they are and yu cant help that, you may want to check if you can have your classes autoloaded prior to that: http://php.net/manual/en/language.oop5.autoload.php

If all else fails, you can still serialize the objects before you store them in a session, and unserialize them each them you retrieve them: http://php.net/manual/en/function.serialize.php

I dont see in your code where you store your variables, but it would be something like

$mystuff = unserialize($_SESSION["mystuff"]);
$mystuff->dostuff();
$_SESSION["mystuff"] = serialize($mystuff);

Be sure to load the class definition before you unserialize your variables

$2c, *-pike

---

I just dealt with something like this. Took me hours to finally find how my order was screwed.

I had a file being called asynchronously.

myFile.php

that file contained the following..

$result = include ("myOtherFile.php");
return $result;

Myotherfile.php has something like this

require_once "lib/myClassLibs.php";
require_once "webconfig.php";

the webconfig.php had the session_start() call in it.

The lib/myClassLibs has all the class info init. If you check before the webconfig call, you can see that the class is available.

If you check before the webconfig call, you will also see that the session has started already. If you check before the lib/myClassLibs.php, you will see the session is already started.

Checking in myFile.php before you include MyOtherFile.php, you find the session has not started.

This represented legacy code that has worked for the last 8 years without me fiddling with it. I pulled the includes out of the "MyOtherFile.php". Now my sessions are synching properly.

---

I solved this problem by including the __autoload function at the top of my php file. So it looks like this:

<?php 
require_once("path/to/include.inc");

//Needed for serialization/deserialization
function __autoload($class_name) {
    include "path/to/". $class_name . '.php';
}

In PHP 5, this function isn't be needed but I was stuck until I used this function. Hope this helps someone else!

---

I know this is a really old question but I ran into this problem. After more research and experimenting I came up with a what I think is an acceptable alternative to storing classes in the session. It might be a bit hackish, but works for my current project.

NOTE: this work-around works for me because I start a session when a user logs in and don't want to include every possible class the user might, or might not encounter during the session. Including all the classes doesn't seem practical or efficient (but maybe this isn't any better ???).

First, my base class contains the following code that populates the object attributes from a given array, automatically.

class BaseClass {

    public function __construct($properties=[]){
        if (!empty($properties)) {
            array_walk($properties, function ($val, $key) {
                $this->fromArray($key, $val);
            });
        }
    }

    public function fromArray($property, $value){
        return (property_exists($this, $property)) ? $this->$property = $value : null;
    }

    public function toArray(){
        return get_object_vars($this);
    }

}

The Work-Around: I use the toArray() method to convert a class instance to an array before it goes into the session, then create a new instance of the class when fetching it from the session.

$_SESSION['user'] = $userInstance->toArray();

// ... do stuff ...

$userInstance = new User($_SESSION['user']);

This is also really handy for writing classes to a database and converting to JSON. Both of which are made easier when working with a PHP array.

Like I said above, this may or may not be the most efficient way to handle this problem. It also raises the question, "should I be using PHP classes if I'm just going to convert to arrays?"

---

I run into the same problem and the solution was inspired by @bobince answer

To be able to do it you have to have defined the class in question before calling session_start

First, my session was set like this:

$_SESSION["customer"] = $customerObj;

Then before calling the session_start(), I have to load or defined the class first by importing it and then call session_start() right after

require 'entity/Customer.php';

ob_start();
session_start();
$customer = new Customer();
if (isset($_SESSION["customer"]))
{
    $customer = $_SESSION["customer"];
    echo $customer->getCustomerName();
}

---

My mistake was sending the user to a PHP page without including the class in that page, only in the original page.

Looked something like this:

index.php

include __DIR__.'AirInfo.php';

session_start();

$plan = new Plan();

header('Location: session.php');

session.php

// Should have put include __DIR__.'AirInfo.php' here
session_start();

---

My mistake here was that I had set the session.auto_start setting to on. The session would then be initialized before any line of code (including the autoloader) will be called.

---

I have the same problem with Google Photo API When Try to Authenticate my app and Access Photo API.

Solve it by just use session_start() after include and all use statements. Here my complete code:

    include "./vendor/autoload.php";
    use Google\Auth\Credentials\UserRefreshCredentials;
    use Google\Photos\Library\V1\PhotosLibraryClient;
    use Google\Photos\Library\V1\PhotosLibraryResourceFactory;
    use Google\Auth\OAuth2;
    session_start();
    //rest of code comes here

---

You might just be calling,

session_start();
session_start();

twice in your code. Call it once. Check required php classes for repeats. This was the fix for me.