diff options
Diffstat (limited to 'itjs.class')
| -rw-r--r-- | itjs.class | 20 |
1 files changed, 20 insertions, 0 deletions
@@ -217,6 +217,26 @@ function crcurl($url) return it::match('#', $url) ? U(trim($url, "#")) : U($url, array('c' => self::checksum(array($fn)))); } +static function far_future_headers() +{ + $crc = $_REQUEST['c'] ?: $_REQUEST['s']; + if ($crc != "-" && !$_SERVER['HTTP_CACHE_CONTROL'] && $_SERVER['HTTP_IF_NONE_MATCH'] && !it::is_devel() && !$_REQUEST['retry']) + { + header("HTTP/1.0 304 Not Modified"); # client should always keep the component that fits the page it has + exit; + } + + if ($crc != "-") + @header("Etag: alwaysvalid"); # we have checksums in the url. client should always keep the version he downloaded along with the html + + if (it::is_live() && !$_REQUEST['retry']) + { + $keeptime = $crc == "-" ? 0 : ($crc ? 30*86400 : 900); # long expire if checksum present + header("Cache-Control: max-age=$keeptime, private"); # proxies should not cache since contents of same url can differ between browsers + header("Expires: " . gmdate("D, d M Y H:i:s", time() + $keeptime). " GMT"); + } +} + } ?> |