A PHP site cache code sharing

/** * @author Seraphim * @copyright 2012 * @link http://bbs.it-home.org */ // function Sendheader ($last _modified, $p _type, $content _length = 0) { Set the client cache validity time Header ("Expires:".) Gmdate ("D, D M Y h:i:s", Time () + 15360000). "GMT"); Header ("cache-control:max-age=315360000"); Header ("Pragma:"); Set Last Modified Time Header ("last-modified:".) $last _modified); Set File type information Header ($p _type); Header ("Content-length:".) $content _length); } Define (' Abspath ', DirName (__file__). '/'); $cache = true; $cachedir = ' cache/'; directory where GZ files are stored, ensuring writable if (Empty ($_server[' query_string ')) Exit (); $gzip = strstr ($_server[' http_accept_encoding '), ' gzip '); if (empty ($gzip)) $cache = false; $key = Array_shift (Explode ('? ', $_server[' query_string ')); $key = Str_replace ('.. /', ', $key); $filename = Abspath. $key; $symbol = ' _ '; $rel _path = Str_replace (Abspath, ", DirName ($filename)); $namespace = Str_replace ('/', $symbol, $rel _path); $cache _filename = Abspath. $cachedir. $namespace. $symbol. BaseName ($filename). '. Gz '; Generate GZ file path $ext = Array_pop (Explode ('. ', $filename)); Determine file type information by suffix $type = "content-type:text/html"; The default file type Switch ($ext) { Case ' CSS ': $type = "Content-type:text/css"; Break Case ' JS ': $type = "Content-type:text/javascript"; Break Case ' gif ': $cache = false; $type = "Content-type:image/gif"; Break Case ' jpg ': $cache = false; $type = "Content-type:image/jpeg"; Break Case ' PNG ': $cache = false; $type = "Content-type:image/png"; Break Default Exit (); } if ($cache) { if (file_exists ($cache _filename)) {//If there is a GZ file $mtime = Filemtime ($cache _filename); $gmt _mtime = gmdate (' d, D M Y h:i:s ', $mtime). ' GMT '; if (Isset ($_server[' http_if_modified_since ') && array_shift (Explode ('; ', $_server[' http_if_modified_ SINCE ']) = = $GMT _mtime)) { Same as the file modification date in the browser cache, returns 304 Header ("http/1.1 304 not Modified"); Send Client Header Header ("Content-encoding:gzip"); Sendheader ($gmt _mtime, $type); } Else { Read GZ file output $content = file_get_contents ($cache _filename); Send Client Header Sendheader ($gmt _mtime, $type, strlen ($content)); Header ("Content-encoding:gzip"); Send data Echo $content; } } Else if (file_exists ($filename)) {//does not have a corresponding GZ file $mtime = Mktime (); $gmt _mtime = gmdate (' d, D M Y h:i:s ', $mtime). ' GMT '; Read file $content = file_get_contents ($filename); Remove the blank part $content = LTrim ($content); Compress file Contents $content = Gzencode ($content, 9, $gzip? Force_gzip:force_deflate); Send Client Header Sendheader ($gmt _mtime, $type, strlen ($content)); Header ("Content-encoding:gzip"); Send data Echo $content; Write file File_put_contents ($cache _filename, $content); } Else { Header ("http/1.0 404 Not Found"); } } Else {//processing does not use the output in gzip mode. The principle of basic ibid. if (file_exists ($filename)) { $mtime = Filemtime ($filename); $gmt _mtime = gmdate (' d, D M Y h:i:s ', $mtime). ' GMT '; if (Isset ($_server[' http_if_modified_since ') && array_shift (Explode ('; ', $_server[' http_if_modified_ SINCE ']) = = $GMT _mtime)) { Same as the file modification date in the browser cache, returns 304 Header ("http/1.1 304 not Modified"); Send Client Header Sendheader ($gmt _mtime, $type, strlen ($content)); Header ("Content-encoding:gzip"); } Else { Read file output $content = file_get_contents ($filename); Send Client Header Sendheader ($gmt _mtime, $type, strlen ($content)); Send data Echo $content; } } Else { Header ("http/1.0 404 Not Found"); } } ?> Copy Code Attached--------------Instructions: 1, the server caches the compressed files, re-access to reduce the re-compression time, reduce CPU utilization. 2, by setting the client file cache time, reduce the number of re-requests, can be reduced by more than 85%. 3, image because it is already compressed format, just set the client cache time, do not do compression processing. Usage: 1, the server must support the Gzip,rewrite feature. 2, add the following code to the following line in the "rewritebase/" of the. htacess file: Rewriterule (. *.css$|. *.js$|. *.jpg$|. *.gif$|. *.png$) gzip.php?$1 [L] 3, upload gzip.php to root directory 4, the root directory to build the cache folder, guaranteed to read and write.

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