How to cache dynamic PHP page

Question

How to cache PHP page which has mysql query. Any example will be great and helpful.

Answer 1

I am using phpFastCache ( for shared hosting, if you don't want to touch php.ini and root to setup memcached). Check out the Example Menu. They have full detail example, and very easy.

First you set with phpFastCache::set and then get with phpFastCache::get - DONE!

Example: Reduce Database Calls

Your website have 10,000 visitors who are online, and your dynamic page have to send 10,000 same queries to database on every page load. With phpFastCache, your page only send 1 query to DB, and use the cache to serve 9,999 other visitors.

<?php
    // In your config file
    include("php_fast_cache.php");
    phpFastCache::$storage = "auto";
    // you can set it to files, apc, memcache, memcached, pdo, or wincache
    // I like auto

    // In your Class, Functions, PHP Pages
    // try to get from Cache first.
    $products = phpFastCache::get("products_page");

    if($products == null) {
        $products = YOUR DB QUERIES || GET_PRODUCTS_FUNCTION;
        // set products in to cache in 600 seconds = 5 minutes
        phpFastCache::set("products_page",$products,600);
    }

   OUTPUT or RETURN your $products
?>

Answer 2

My preference is to use a caching reverse proxy, like Varnish.

As far as a pure PHP solution, you could have some code at the end of your script that caches the final output, and code at the beginning that checks to see if the page is cached. If the page was found in cache, send it and exit rather than running the queries again.

<?php

function cache_file() {
    // something to (hopefully) uniquely identify the resource
    $cache_key = md5($_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] . $_SERVER['QUERY_STRING']);
    $cache_dir = '/tmp/phpcache';

    return $cache_dir . '/' . $cache_key;
}

// if we have a cache file, deliver it
if( is_file( $cache_file = cache_file() ) ) {
    readfile( $cache_file );
    exit;
}

// cache via output buffering, with callback
ob_start( 'cache_output' );

//
// expensive processing happens here, along with page output.
//

function cache_output( $content ) {
    file_put_contents( cache_file(), $content );
    return $content;
}

Obviously this needs lots of customization for your setup, including cache expiration, a $cache_key that meets your needs, and error detection so bad pages aren't cached.

Answer 3

memcache your html out and then do something like this:

$memcache = memcache_connect('localhost', 11211);

$page  = $memcache->get('homepage');
if($page == ""){
    $mtime = microtime();
    $page = get_home();
    $mtime = explode(" ",$mtime);
    $mtime = $mtime[1] + $mtime[0];
    $endtime = $mtime;
    $totaltime = ($endtime - $starttime);
    memcache_set($memcache, 'homepage', $page, 0, 30);
    $page .= "\n<!-- Duly stored ($totaltime) -->";
}
else{
    $mtime = microtime();
    $mtime = explode(" ",$mtime);
    $mtime = $mtime[1] + $mtime[0];
    $endtime = $mtime;
    $totaltime = ($endtime - $starttime);
    $page .= "\n&lt;!-- served from memcache ($totaltime) -->";
}
die($page);