PHP: Zend Framework, MVC, Cookies and 4096 byte oddities

A little word of warning which has puzzled me for over 3 hours in debugging…

If you use Zend_Controller_Front::getInstance()->dispatch(); in your Zend Framework index.php file for firing off the MVC system, and the returned page is over 4096 bytes (4 kilobytes) in size you cannot set a cookie afterwards without causing the “fun” error “Cannot modify header information – headers already sent by (output started at …/library/Zend/Controller/Response/Abstract.php:546) in …”

To work around this, you’ll need to change the code from just:

Zend_Controller_Front::getInstance()->dispatch();
setcookie(. . .);

to:

$front=Zend_Controller_Front::getInstance();
$front->returnResponse(true);
$response=$front->dispatch();
#Zend_Controller_Front::getInstance()->dispatch();
setcookie(. . .);
$response->sendResponse();

I’m sure there is a slightly better way of setting Cookies in the Zend Framework, but that’s a work around for the normal way I’ve found.

If you’ve got any “better idea” suggestions, just let me know.

(I found this “buglet” because a drop down select menu I was making with Zend Form Element was causing the “Cannot modify header information – headers already sent by” error once a number of items were listed: it took 3 hours+ of detection work to narrow it down to a content size issue, then it was a process of elimination ruling out Zend_Form_Element, Zend_Form, Zend_View and Zend_View_Abstract (which helped a bit with the debugging on the issue) and then to Zend_Controller_Front to Zend_Controller_Response_Http and finally to Zend_Controller_Response_Abstract)