trying to Clear browser site cache in php,
for firefox browser is working fine, as we want but when i run in chrome it didnt work.
see code,
header('Clear-Site-Data: "cache", "cookies", "storage", "executionContexts"'); //Firefox
// Crome
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header ("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header ("Cache-Control: no-cache, must-revalidate");
header ("Pragma: no-cache");
header('Clear-Site-Data: "cookies"');
return $this->getSuccessResponse("Token Valid");
I think you can't clear cache from browser perfectly, one only option is you can do manually. There is some code. I hope it will work.
<?php
header("Expires: Tue, 01 Jan 2000 00:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");
?>
I have written a PHP page which reads a file and does echo it after adding some headers:
header('Content-disposition: filename="' . $fname . '"');
header('Pragma: no-cache');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header("Content-type: $AttachFileType");
header("Content-Transfer-Encoding: binary");
header("Content-Length: " . filesize($ffullname));
echo file_get_contents($ffullname);
This piece of code does well on local test, but when porting to the server, the response is not as expected. For example when I want to retrieve a png file, I get the below image on local test:
while server test outputs this one:
As I have investigated, the only difference of them is 4 additional headers on server response. Local test response headers:
Cache-Control: must-revalidate, post-check=0, pre-check=0
Connection: Keep-Alive
Content-disposition: filename="attachment_hrmstotal_generalskills_6.png"
Content-Length: 2401
Content-Transfer-Encoding: binary
Content-Type: png
Date: Wed, 23 May 2018 04:45:02 GMT
Expires: 0
Keep-Alive: timeout=5, max=97
Pragma: public
Server: Apache/2.4.27 (Ubuntu)
and server response headers are these:
Cache-Control: must-revalidate, post-check=0, pre-check=0
Connection: keep-alive
Content-disposition: filename="attachment_hrmstotal_generalskills_1.png"
Content-Length: 184450
Content-Transfer-Encoding: binary
Content-Type: png
Date: Wed, 23 May 2018 04:40:56 GMT
Expires: 0
Pragma: public
Server: nginx/1.8.0
Strict-Transport-Security: max-age=31536000
X-Content-Type-Options: nosniff
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
The last four headers is the difference. What is the problem, its reason and how to solve it?
Your content-type should be Content-type: image/png
So I have this at the very top of my PHP file:
<?php
// Set headers
header('Content-Type: text/html; charset=UTF-8');
header('Content-Style-Type: text/css');
header('Content-Script-Type: application/javascript');
header('HTTP/1.1 200 OK');
header('Content-language: en-US');
header('X-Powered-By: ');
header_remove('X-Powered-By');
header('Last-Modified: Tue, 01 Jan 2013 00:00:00 GMT');
header('Cache-Control: no-store, no-cache, max-age=0, must-revalidate');
header('Pragma: no-store, no-cache, max-age=0, must-revalidate');
header('Expires: Tue, 01 Jan 2013 00:00:00 GMT');
?>
So when I check the Firefox console's NET tab on my site's URL I don't see the Last-Modified header. Any suggestions?
You're telling the browser to cache nothing and he MUST revalidate everything. So the last-modified header doesn't matter.
Guys please tell me how to prevent from session restore on back button in ubuntu ?
session_cache_limiter( FALSE );
session_start();
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: max-age=0, no-cache, no-store, must-revalidate, post-check=0, pre-check=0'");
header("Pragma: no-cache");
header("Cache-Control: post-check=0, pre-check=0", FALSE);
this works in xp but not in ubuntu.
could anyone help me with setting up Expire Headers using PHP only,
.htaccess is no good, because my host won't enable mod_expires on apache.
So basically I'm looking for a way to do:
Expire Header
<FilesMatch "\.(ico|jpg|jpeg|png|gif|js|css|swf)$">
ExpiresDefault "access plus 365 days"
</FilesMatch>
with php only.
its also important to have different expire periods for different filetypes, so I tried using something like:
header ("content-type: image/jpg; charset: UTF-8");
header ("cache-control: must-revalidate");
$offset = 48 * 60 * 60;
$expire = "expires: " . gmdate ("D, d M Y H:i:s", time() + $offset) . " GMT";
header ($expire);
for each type of files, but nothing happened.
the headers after adding the PHP code, and taken from private session:
Response Headersview source
Date Mon, 25 Apr 2011 19:47:10 GMT
Server Apache/2.2.14 (Unix) DAV/2 mod_ssl/2.2.14 OpenSSL/0.9.8l PHP/5.3.1 mod_apreq2-20090110/2.7.1 mod_perl/2.0.4 Perl/v5.10.1
X-Powered-By PHP/5.3.1
P3P CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM"
Expires Mon, 1 Jan 2001 00:00:00 GMT
Cache-Control no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Last-Modified Mon, 25 Apr 2011 19:47:10 GMT
Content-Encoding gzip
Pragma no-cache
Keep-Alive timeout=5, max=100
Connection Keep-Alive
Transfer-Encoding chunked
Content-Type text/html; charset=utf-8
Request Headersview source
Host localhost
User-Agent Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.16) Gecko/20110323 Ubuntu/10.10 (maverick) Firefox/3.6.16 ( .NET CLR 3.5.30729) FirePHP/0.5
Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language en-us,en;q=0.7,he;q=0.3
Accept-Encoding gzip,deflate
Accept-Charset ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive 115
Connection keep-alive
Referer http://localhost/-----------------
Cookie fboard_settings[current_view]=flat; style_cookie=null; phpbb3_4s1go_k=; phpbb3_4s1go_u=2; phpbb3_4s1go_sid=8a3835a63834e9851b0cde3e2f6cff63; jw_clean_pro_tpl=jw_clean_pro; acpSearchCookie[searchphrase]=any; acpSearchCookie[acpSearch]=%D7%97%D7%A4%D7%A9+...; acpSearchCookie[cid]=0; acpSearchCookie[field_city]=0; 14a2bb08766d6180968b7925b7902d70=bgd3h1uj5dctoevtdiaj1jtmg6; 3e2fd857422e2463a01f9631f718017a=nbdjbmjsn9ee8ng90ui816hec2
x-insight activate
According to your comment in the question it looks like your system is running with a PHP setting of session.cache_limiter = nocache. This would automatically send the following headers:
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Only the Expires header you mention differs a bit (afaik Joomla uses that very datetime, if i'm not mistaken). But all in all it makes no difference, because both dates are in the past.
You should try with session_cache_limiter(false); in your code, to stop PHP sending its default caching headers:
function sendHeader($sType, $iLastModified, $iSecondsToCache)
{
$aType = array(
'ico' => 'image/x-icon',
'jpg' => 'image/jpeg',
'png' => 'image/png',
'gif' => 'image/gif',
'js' => 'text/javascript',
'css' => 'text/css',
'swf' => 'application/x-shockwave-flash'
);
if (!isset($aType[$sType]))
die('No mime type found for ' . $sType);
//$sLastModified = gmdate('r', $iLastModified);
$sLastModified = gmdate('D, d M Y H:i:s', $iLastModified) . ' GMT';
if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']))
{
if ($_SERVER['HTTP_IF_MODIFIED_SINCE'] == $sLastModified)
{
header('HTTP/1.1 304 Not Modified');
exit;
}
}
session_cache_limiter(false);
//header('Expires: ' . gmdate('r', $iLastModified + $iSecondsToCache));
header('Expires: ' . gmdate('D, d M Y H:i:s', $iLastModified + $iSecondsToCache) . ' GMT');
header('Cache-Control: public');
header('Last-Modified: ' . $sLastModified);
header('Content-Type: ' . $aType[$sType]);
}
date_default_timezone_set('Europe/Berlin');
$iLastModified = strtotime('2011-04-25 07:08:09');
$iSecondsToCache = 48 * 60 * 60;
sendHeader('jpg', $iLastModified, $iSecondsToCache);
// stream sample image/jpeg content
$rGD = imagecreatetruecolor(100, 20);
$iColor = imagecolorallocate($rGD, 255, 255, 255);
imagestring($rGD, 1, 5, 5, 'Image to be cached', $iColor);
imagejpeg($rGD);
imagedestroy($rGD);
exit;
EDIT:
Meanwhile it's more probable to me, that Joomla is causing the problem. If the test code has access to Joomla libraries, try inserting:
jimport('joomla.environment.response');
JResponse::allowCache(true);
at the very top of the function and replace each header instruction with JResponse::setHeader.
That helps me for ajax queries:
header( 'Expires: Sat, 26 Jul 1997 05:00:00 GMT' );
header( 'Last-Modified: ' . gmdate( 'D, d M Y H:i:s',time()+60*60*8 ) . ' GMT' );
header( 'Cache-Control: no-store, no-cache, must-revalidate' );
header( 'Cache-Control: post-check=0, pre-check=0', false );
header( 'Pragma: no-cache' );