Caching HTML output with PHP

check ob_start() function

ob_start();
echo 'some_output';
$content = ob_get_contents();
ob_end_clean();

echo 'Content generated :'.$content;

You can get URLs like that using URL rewriting. Eg: for apache, see mod_rewrite

http://httpd.apache.org/docs/2.2/mod/mod_rewrite.html

You don't actually need to be creating the files. You could create the files, but its more complicated as you need to decide when to update them if the data changes.

Manual caching (creating the HTML and saving it to a file) may not be the most efficient way, but if you want to go down that path I recommend the following (ripped from a simple test app I wrote to do this):

$cache_filename = basename($_SERVER['PHP_SELF']) . "?" . $_SERVER['QUERY_STRING'];
$cache_limit_in_mins = 60 * 32; // this forms 32hrs
// check if we have a cached file already
if ( file_exists($cache_filename) )
{
    $secs_in_min = 60;
    $diff_in_secs = (time() - ($secs_in_min * $cache_limit_in_mins)) - filemtime($cache_filename);
    // check if the cached file is older than our limit
    if ( $diff_in_secs < 0 )
    {
        // it isn't, so display it to the user and stop
        print file_get_contents($cache_filename);
        exit();
    }
}

// create an array to hold your HTML output, this is where you generate your HTML
$output = array();
$output[] = '<table>';
$output[] = '<tr>';
// etc

//  Save the output as manual cache
$file = fopen ( $cache_filename, 'w' );
fwrite ( $file, implode($output,'') );
fclose ( $file );

print implode($output,'');

In my opinion this is the best solution. I use this for cache JSON file for my Android App. It can be simply use in other PHP files. It's optimize file size from ~1mb to ~163kb (gzip).

Create cache folder in your directory

Then Create cache_start.php file and paste this code

<?php
header("HTTP/1.1 200 OK");
//header("Content-Type: application/json"); 
header("Content-Encoding: gzip");

$cache_filename = basename($_SERVER['PHP_SELF']) . "?" . $_SERVER['QUERY_STRING'];
$cache_filename = "./cache/".md5($cache_filename);
$cache_limit_in_mins = 60 * 60; // It's one hour


if (file_exists($cache_filename))
{
    $secs_in_min = 60;
    $diff_in_secs = (time() - ($secs_in_min * $cache_limit_in_mins)) - filemtime($cache_filename);
    if ( $diff_in_secs < 0 )
    {
        print gzencode( file_get_contents($cache_filename) );
        exit();
    }
}
ob_start("ob_gzhandler");
?>

Create cache_end.php and paste this code

<?php
$content = ob_get_contents();
ob_end_clean();
$file = fopen ( $cache_filename, 'w' );
fwrite ( $file, $content );
fclose ( $file );
echo gzencode( $content );
?>

Then create for example index.php (file which you want to cache)

<?php
include "cache_start.php";
echo "Hello Compress Cache World!";
include "cache_end.php";
?>

I use APC for all my PHP caching (on an Apache server)

If you're not opposed to frameworks, try using the Zend Frameworks's Zend_Cache. It's pretty flexible, and (unlike some of the framework modules) easy to implement.

Can use Cache_lite from PEAR:

Details here http://mahtonu.wordpress.com/2009/09/25/cache-php-output-for-high-traffic-websites-pear-cache_lite/

I was thinking from the point of load on the database, and charges for data bandwidth and speed of loading. I have some pages which are unlikely to change in years, (I know it is easy to use a CMS system based on a database ). Unlike in US, here the cost of bandwidth can be high. Anybody has any views on that, whether to create htmal pages or dynamic (php, asp.net) Links to the pages would be stored on a database anyway.