[Forum] How to specify a short cache time in vBulletin 4 headinclude template

[djbaxter]

Using vBulletin 4.2.5.

Problem: Sometimes a mobile browser on a slow data connection will not download all the CSS correctly, breaking the page displayed in the default vBulletin mobile style. Refreshing the page doesn't help, at least not for some time and I have no idea what the default expiration time is for mobile devices/browsers.

I don't want to turn off caching completely.

What I want to do is specify a short cache time, say 5 minutes.

I'm having trouble finding the correct syntax for this.

Is this correct?

<meta http-equiv="Cache-Control" content="must-revalidate, max-age=300" />

or should it be

<meta http-equiv="Cache-Control: must-revalidate, max-age=300" />

or is there a better way to do this.

Additionally, can this be done only for mobile devices by inserting the meta tag just into the default mobile style?

[Wayne Luke]

There is no Cache-Control value for http-equiv supported by the standard. Due to this, not all browsers will support it. You should handle this in the web server (.htaccess) or via PHP (using the header() function).

https://developer.mozilla.org/en-US/...L/Element/meta
https://developer.mozilla.org/en-US/.../Cache-Control

To do this in PHP, search the includes/init.php file for "mobile".

You'll need something like:

<?php
  //set headers to NOT cache a page
  header("Cache-Control: no-cache, must-revalidate"); //HTTP 1.1
  header("Pragma: no-cache"); //HTTP 1.0
  header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past

  //or, if you DO want a file to cache, use:
  header("Cache-Control: max-age=2592000"); //30days (60sec * 60min * 24hours * 30days)

?>

[Wayne Luke]

With vBulletin 5.X, we use this in the .htaccess file:

<IfModule mod_expires.c>
	ExpiresActive On
	ExpiresByType application/x-javascript A1209600
	ExpiresByType text/javascript A1209600
	ExpiresByType application/javascript A1209600
	ExpiresByType text/css A31536000
	ExpiresByType image/x-icon A2592000
	ExpiresByType image/icon A2592000
	ExpiresByType application/x-ico A2592000
	ExpiresByType application/ico A2592000
	ExpiresByType image/gif A2592000
	ExpiresByType image/jpeg A1209600
	ExpiresByType image/jpg A1209600
	ExpiresByType image/png A1209600
	ExpiresByType application/x-shockwave-flash A1209600
	ExpiresByType font/ttf A2592000
	ExpiresByType font/otf A2592000
	ExpiresByType font/x-woff A2592000
	ExpiresByType image/svg+xml A2592000
	ExpiresByType font/truetype A2592000
	ExpiresByType font/opentype A2592000
	ExpiresByType application/x-font-woff A2592000
	ExpiresByType application/vnd.ms-fontobject A2592000
</IfModule>

<IfModule mod_headers.c>
    Header set Connection keep-alive
	<filesmatch "\.(ico|flv|gif|swf|eot|woff|otf|ttf|svg)$">
		Header set Cache-Control "max-age=2592000, public"
	</filesmatch>
	<filesmatch "\.(jpg|jpeg|png)$">
		Header set Cache-Control "max-age=1209600, public"
	</filesmatch>
	<filesmatch "\.(eot|woff|otf|ttf|svg)$">
		Header set Cache-Control "max-age=2592000, public"
	</filesmatch>
	# css and js should use private for proxy caching https://developers.google.com/speed/docs/best-practices/caching#LeverageProxyCaching
	<filesmatch "\.(css)$">
		Header set Cache-Control "max-age=31536000, private"
	</filesmatch>
	<filesmatch "\.(js)$">
		Header set Cache-Control "max-age=1209600, private"
	</filesmatch>
</IfModule>

[djbaxter]

Thanks, Wayne.

For an Apache server, what would the appropriate htaccess addition look like?

You added your post above while I was posting this. Thanks, again.