Object of class upload could not be converted to string ... in attributes_controller

[vasilt]

Just upgraded from 1.3.9 by fresh install and applying all customizations and language files as well as the CKEditor. When trying to edit prices of products in the attributes controller, page goes blank after hitting the update button.
The error log is:

[12-Jul-2016 20:00:15] Request URI:/cart/admin/attributes_controller.php?action=update_product_attribute&attribute_page=1&products_filter=157, IP address: .............
#1  trim(upload Object ([file] => attributes_image,[filename] => ,[destination] =>/home/company/public_html/cart/images/,[permissions] => 420,[extensions] => Array ([0] =>jpg,[1] => jpeg,[2] => gif,[3] => png,[4] => webp,[5] => flv,[6] => webm,[7] =>ogg),[tmp_filename] => ,[message_location] => direct)) called at [/home/company/public_html/cart/admin/includes/functions/general.php:441]
#2  zen_not_null(upload Object ([file] => attributes_image,[filename] => ,[destination] =>/home/company/public_html/cart/images/,[permissions] => 420,[extensions] => Array ([0] =>jpg,[1] => jpeg,[2] => gif,[3] => png,[4] => webp,[5] => flv,[6] => webm,[7] =>ogg),[tmp_filename] => ,[message_location] => direct)) called at [/home/company/public_html/cart/admin/includes/classes/upload.php:61]
#3  upload->parse() called at [/home/company/public_html/cart/admin/attributes_controller.php:445]

[12-Jul-2016 20:00:15] PHP Catchable fatal error:  Object of class upload could not be converted to string in /home/company/public_html/cart/admin/includes/functions/general.php on line 441

The reason seems to be that the function zen_not_null($value) in admin/includes/functions/general.php does not handle objects while we have this construct:

$attributes_image = new upload('attributes_image');

on line 442 in admin/attributes_controller.php

PHP Version 5.2.17 MySQL: 5.5.50

[DrByte]

1. I'd strongly encourage you to get your server upgraded to a more modern version of PHP now that you're using a ZC version that supports it.

2. The symptom you've reported is probably a bug, and probably only occurs when you don't have an image set on the attribute and aren't trying to actually upload a new one.
Here's a bandage which I think will work for you:
/admin/includes/classes/upload.php
change line 58 from:

'tmp_name' => (isset($GLOBALS[$this->file]) ? $GLOBALS[$this->file] : ''));

to:

'tmp_name' => (isset($GLOBALS[$this->file]) && is_string($GLOBALS[$this->file]) ? $GLOBALS[$this->file] : ''));

And then test by updating those attributes, preferably one with... and one without ... an attribute image ;)

[mc12345678]

I've recently uploaded an attribute with and without an attribute image, but using a newer php version. While I haven't gone back (yet) to look at how the applicable file handling changed over the versions, are you thinking it to be a bug related to older PHP (reported to be compatible with this version of ZC), or a bug in general (not discovered when using php 5.6).

[DrByte]

In looking at the code I'm thinking it's a bug in general: if $_FILES isn't set (which *is* set when an actual upload exists, in modern PHP), then it looks for a very old HTTP_POST_FILES array (which won't exist in modern PHP), and then "else" is where the above code is failing ... because the tmp_name is getting set to a string value but is being passed a global object which happens to be named the same as the variable which is the instance of the upload class ... basically a circular loop. This class was inherited from osC back in 2003 and this particular section hasn't been touched but clearly needs an overhaul for modern use.

That said, I'm very surprised this hasn't come up a million times already ... cuz it's not an issue unique to PHP 5.2 nor PHP 7.

Maybe the OP has the deprecated "register_globals" enabled or something?

[vasilt]

The quick-fix of DrByte did the job. Attributes image are disabled in admin so I tested only this alternative. Hopefully, I will manage to test with attributes images enabled in the next few days and I will let you know if any problems arise. The "register_globals" is off and I agree with DrByte that its really amazing that this bug-candidate hasn't come up a million times already.

[mc12345678]

The quick-fix of DrByte did the job. Attributes image are disabled in admin so I tested only this alternative. Hopefully, I will manage to test with attributes images enabled in the next few days and I will let you know if any problems arise. The "register_globals" is off and I agree with DrByte that its really amazing that this bug-candidate hasn't come up a million times already.

Mind also posting the first 80-100 lines of the php results seen from the admin when the version link/button is pressed? Perhaps there is something there that could help the good Dr. identify why those issues didn't appear (assuming knowing the why is of importance).