PHP website cache Acceleration

Note:
1. the compressed files are cached on the server, and the re-access reduces the re-compression time to reduce the CPU usage.
2. You can set the Client File Cache Time to reduce the number of re-requests by more than 85%.
3. Because the image is already in the compression format, it only sets the client cache time and does not compress the image.

Usage:
1. The server must support the gzip and Rewrite functions.
2. Add the following code under the RewriteBase/line of the. htacess file, as shown in the figure below.
RewriteRule (. *. css $ |. *. js $ |. *. jpg $ |. *. gif $ |. *. png $) gzip. php? $1 [L]
3. Upload gzip. php to the root directory.
4. Create a cache folder in the root directory to ensure read/write.

Copy codeThe Code is as follows: <? Php
/**
* @ Author Seraphim
* @ Copyright 2012
*/
// <! -- Common subprograms for returning headers -->
Function sendheader ($ last_modified, $ p_type, $ content_length = 0)
{
// Set the Client Cache Validity Period
Header ("Expires:". gmdate ("D, d m y h: I: s", time () + 15360000). "GMT ");
Header ("Cache-Control: max-age = 315360000 ");
Header ("Pragma :");
// Set the last modification 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 for storing the gz file to ensure that the file can be written
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 the gz file path
$ Ext = array_pop (explode ('.', $ filename); // you can specify the file type based on the suffix.
$ Type = "Content-type: text/html"; // 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 the gz file exists
$ 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 ))
{
// The file modification date is the same as that in the browser cache, and 304 is returned.
Header ("HTTP/1.1 304 Not Modified ");
// Send the client header
Header ("Content-Encoding: gzip ");
Sendheader ($ gmt_mtime, $ type );
}
Else
{
// Read the gz file output
$ Content = file_get_contents ($ cache_filename );
// Send the client header
Sendheader ($ gmt_mtime, $ type, strlen ($ content ));
Header ("Content-Encoding: gzip ");
// Send data
Echo $ content;
}
}
Else
If (file_exists ($ filename ))
{// No corresponding gz File
$ Mtime = mktime ();
$ Gmt_mtime = gmdate ('d, d m y h: I: s', $ mtime). 'gmt ';
// Read the file
$ Content = file_get_contents ($ filename );
// Remove the blank part
// $ Content = ltrim ($ content );
// Compress the File Content
$ Content = gzencode ($ content, 9, $ gzip? FORCE_GZIP: FORCE_DEFLATE );
// Send the client header
Sendheader ($ gmt_mtime, $ type, strlen ($ content ));
Header ("Content-Encoding: gzip ");
// Send data
Echo $ content;
// Write a file
File_put_contents ($ cache_filename, $ content );
}
Else
{
Header ("HTTP/1.0 404 Not Found ");
}
}
Else
{// The output in Gzip mode is not used for processing. The principle is basically the same as above.
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 ))
{
// The file modification date is the same as that in the browser cache, and 304 is returned.
Header ("HTTP/1.1 304 Not Modified ");
// Send the client header
Sendheader ($ gmt_mtime, $ type, strlen ($ content ));
Header ("Content-Encoding: gzip ");
}
Else
{
// Read file output
$ Content = file_get_contents ($ filename );
// Send the client header
Sendheader ($ gmt_mtime, $ type, strlen ($ content ));
// Send data
Echo $ content;
}
}
Else
{
Header ("HTTP/1.0 404 Not Found ");
}
}
?>