LSCache PURGE

As of 4.1.12, LSWS supports cache PURGE operation to accommodate the demand on cache manipulation.

Here are the steps to PURGE cache:

<?php
$fp = fsockopen('192.168.0.81', 80, $errno, $errstr, 2);
if (!$fp) {
    echo "$errstr ($errno)\n";
} else {
    $out = "PURGE /hello.php HTTP/1.0\r\n"
    . "Host: www.example.com\r\n"
    //. "Authorization: Basic ".base64_encode("userid:password")."\r\n"
    . "Connection: Close\r\n\r\n";
    fwrite($fp, $out);
    echo $out;
    while (!feof($fp)) {
        echo fgets($fp, 128);
    }
    fclose($fp);
}
?>

Note:

1. We are using internal IP address 192.168.0.80 for illustration purposes only. In a real world application, make sure that vhost listens on 192.168.0.80 for domain name http://example.com.
2. Authentication can be added to make the PURGE more secure. Comments in the script simplify the process.

put the following rules in .htaccess

RewriteEngine On
RewriteCond %{REQUEST_METHOD} ^HEAD|GET|PURGE$
RewriteCond %{REQUEST_URI} !^/purge\.php$
RewriteRule .* - [E=Cache-Control:max-age=120,L]

Note: PURGE needs to be in the allowed method.

Admin Console ⇒ Configuration ⇒ Server ⇒ Security ⇒ Allow List

append Source_IP with tailing 'T' for trusted IP like 'ALL, 192.168.0.81T'

1.1 point browser to http://www.example.com/hello.php

1.2 cache storage has a new file created for hello.php (for illustration purposes, we cleaned cache storage in our lab prior to step 1).

[root@cptest diskcache]# ls -lrt */*/*
9/c/6:
total 12
-rw------- 1 nobody nobody 11638 May  2 15:42 9c6eae83978ecd87

[root@cptest diskcache]#

request http://www.example.com/hello.php again from browser. receive 'X-Litespeed-Cache: hit' response header as a prove 

   Date: Wed, 02 May 2012 23:59:53 GMT
   Content-Encoding: gzip
   X-Litespeed-Cache: hit   <=== here it is
   Connection: Keep-Alive
   Content-Length: 10
   Server: LiteSpeed
   Vary: Accept-Encoding
   Content-Type: text/html
   Keep-Alive: timeout=5, max=100

3.1 1st time, '200 Purged' status returned.

   [test@test ~]$ php purge.php
   PURGE /hello.php HTTP/1.0
   Host: www.example.com
   Connection: Close

   HTTP/1.0 200 Purged
   Date: Wed, 02 May 2012 23:48:23 GMT
   Server: LiteSpeed
   Connection: close

   [test@test ~]$ 

Note: 'HTTP/1.0 200 Purged' indicates the resource is purged.

Rewrite Log shown

2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] strip base: '/' from URI: '/phpinfo.php'
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] Rule: Match 'phpinfo.php' with pattern '.*', result: 
1
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] Cond: Match 'PURGE' with pattern '^HEAD|GET|PURGE$', 
result: 1
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] Cond: Match '/phpinfo.php' with pattern '^/purge\.php
$', result: -1
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] apply cache-control: 'max-age=120'.
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] No substition
2012-05-02 15:43:20.280 [INFO] [192.168.0.81:60174-0#APVH_lstest.com] [REWRITE] Last Rule, stop!
2012-05-02 15:43:20.281 [NOTICE] [192.168.0.81:60174-0#APVH_lstest.com:cache] [PUBLIC CACHE] PURGE /phpinfo.php, result: 1
2012-05-02 15:43:20.281 [DEBUG] [192.168.0.81:60174-0#APVH_lstest.com:cache] HttpConnection::sendHttpError(),code=200 Purged

 ...

3.2 2nd purge request results in 405 error

   [test@test ~]$ php purge.php
   PURGE /hello.php HTTP/1.0
   Host: www.lstest.com
   Connection: Close

   HTTP/1.0 405 Method Not Allowed
   Date: Wed, 02 May 2012 23:37:44 GMT
   Server: LiteSpeed
   Connection: close
   Cache-Control: private, no-cache, max-age=0
   Pragma: no-cache
   Content-Type: text/html
   Content-Length: 383

   [test@test ~]$

Rewrite Log shown

2012-05-02 15:43:39.588 [NOTICE] [192.168.0.81:60175-0#APVH_lstest.com] Content len: 0, Request line: 'PURGE /phpinfo.php HTTP/1.1'
2012-05-02 15:43:39.588 [DEBUG] [192.168.0.81:60175-0#APVH_lstest.com] Find context with URI: [/], location: [/home/lstestc/public_html/]
...
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] strip base: '/' from URI: '/phpinfo.php'
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] Rule: Match 'phpinfo.php' with pattern '.*', result: 1
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] Cond: Match 'PURGE' with pattern '^HEAD|GET|PURGE$', result: 1
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] Cond: Match '/phpinfo.php' with pattern '^/purge\.php$', result: -1
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] apply cache-control: 'max-age=120'.
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] No substition
2012-05-02 15:43:39.588 [INFO] [192.168.0.81:60175-0#APVH_lstest.com] [REWRITE] Last Rule, stop!
2012-05-02 15:43:39.588 [DEBUG] [192.168.0.81:60175-0#APVH_lstest.com] HttpConnection::sendHttpError(),code=405 Method Not Allowed
2012-05-02 15:43:39.588 [DEBUG] [192.168.0.81:60175-0#APVH_lstest.com] redirect to: 
        URI=[/405.shtml],
        QueryString=[]

4.1 check cache file -- gone

   [test@test ~]$ ls -lrt */*/*

   9/c/6:
   total 0
   [test@test ~]$ 

4.2 request resource 3rd time from browser, *no* 'X-Litespeed-Cache: hit' response header received.

   Date: Wed, 02 May 2012 23:42:18 GMT
   Content-Encoding: gzip
   Transfer-Encoding: Identity
   Connection: close
   Server: LiteSpeed
   Vary: Accept-Encoding
   Content-Type: text/html