I’m outputting an image to the browser using a Zend_Controller_Response object. It is my intention to apply caching to the image, however something is causing the Cache-Control header to be overwritten.
My code is as follows:
$this->getResponse() ->setHeader('Last-Modified', $modifiedTime, true) ->setHeader('ETag', md5($modifiedTime), true) ->setHeader('Expires', $expires, true) ->setHeader('Pragma', '', true) ->setHeader('Cache-Control', 'max-age=3600') ->setHeader('Content-Type', $mimeType, true) ->setHeader('Content-Length', $size, true) ->setBody($data); The output (as viewed in Firebug) is:
Response Headers
- Date
- Wed, 25 Mar 2009 10:34:40 GMT
- Server
- Apache/2.2.3 (Ubuntu) mod_ssl/2.2.3 OpenSSL/0.9.8c
- Expires
- Thu, 26 Mar 2009 10:34:41 GMT
- Cache-Control
- no-store, no-cache, must-revalidate, post-check=0, pre-check=0, max-age=3600
- Last-Modified
- 1234872514
- Etag
- d3ef646c640b689b0101f3e03e08a524
- Content-Length
- 1452
- X-UA-Compatible
- IE=EmulateIE7
- X-Robots-Tag
- noindex
- Keep-Alive
- timeout=15, max=100
- Connection
- Keep-Alive
- Content-Type
- image/jpeg
Request Headers
- Host
- khall.####.###.######.com
- User-Agent
- Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.7) Gecko/2009030422 Ubuntu/8.04 (hardy) Firefox/3.0 .7
- Accept
- text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
- Accept-Language
- en-gb,en;q=0.5
- Accept-Encoding
- gzip,deflate
- Accept-Charset
- ISO-8859-1,utf-8;q=0.7,*;q=0.7
- Keep-Alive
- 300
- Connection
- keep-alive
- Referer
- http://khall.####.###.######.com/
- Cookie
- PHPSESSID=abf5056e1289d3010448107632a1c1bd
As you can see, the cache control is modified to include:
no-store, no-cache, must-revalidate, post-check=0, pre-check=0
My suspicion is towards the session cookie being sent in the request. Does anybody know a way to send the header that I require, yet still keep the session in the request? My application is run through a bootstrap, and sessions are handled using Zend_Session.
Any help would be appreciated.
From the Zend_Controller documentation, section 10.9. The Response Object
The problem you are having is your max-age=3600 is being appended to the cache-control header, as opposed to replacing it. Try setting the $replace parameter to true.