Arbitrary redis caching of output and serializable objects

redis.php

<?php

// Needs a global $redis_config
function get_redis($force=false) {
    global $redis_config,$redis_instance;

    if(!is_object($redis_config))
        die("Couldn't find \$redis_config or it's not an object!");

    // No redis? No problem! 
    if(!class_exists('Redis') || !extension_loaded('redis')) {
        $redis_instance = new Fake_Redis();
        return $redis_instance;
    }

    if(!$redis_instance || $force !== false) {
        $redis_instance = new Redis();
        $redis_ip = $redis_config->ip;
        if(!$redis_ip)
            $redis_ip = 'localhost';
        $redis_instance->connect($redis_ip);

        // Let's keep the redis databases separate!
        if(!isset($redis_config->db_id))
            die('Warning! No redis db selected');
        else
            $redis_instance->select($redis_config->db_id);
    }

    return $redis_instance;
}

// Base class for a cached object, represents one redis entry
class Redis_Cache {

    var $key_prefix = '';
    
    function __construct($user_key,$opts='') {
        $default_opts = array(
            'output_cache' => true,
            'profile' => false,
            'profile_noisy' => true,
            'expires' => false
        );
      
        $this->opts = array_merge($default_opts,(array)$opts);

        if(isset($_GET['redis_debug']))
            $this->opts['profile'] = true;

        // We add info to our keys
        $this->user_key = $user_key;
        $this->key = $user_key;
        
        if($this->key_prefix !== '')
            $this->key = "$this->key_prefix:$this->key";

        $this->redis = get_redis();
        $this->cache = $this->redis->get($this->key);

        // Bust the cache!
        if(isset($_GET['redis_bust']))
            $this->cache = false;

        $this->cache_hit = $this->cache !== false;
        $this->cache_miss = !$this->cache_hit;
        $this->cache_hit_str = $this->cache !== false ? 'hit' : 'miss';
    }

    function write_cache($val,$expires=false) {
        if(!$expires)
            $expires = $this->opts['expires'];

        if($expires)
            return $this->redis->setex($this->key,$expires,$val);
        
        $this->redis->set($this->key,$val);
    }

    function profile_start($noisy=true) {
        if(!$this->opts['profile'])
            return;
        $this->time_start = microtime(true);
        if($noisy && $this->opts['profile_noisy'])
            echo "\n\n<!-- REDIS BEGIN: $this->user_key, $this->cache_hit_str -->\n\n";
    }

    function profile_end($noisy=true) {
        if(!$this->opts['profile'])
            return;
        $this->time_end = microtime(true);
        $this->time_delta = round($this->time_end - $this->time_start,5);
        if($noisy && $this->opts['profile_noisy'])
            echo "\n\n<!-- REDIS END: $this->user_key, $this->cache_hit_str, $this->time_delta -->\n\n";
    }
}

// Redis output buffering for caching arbitrary output
// You have to do the (strict) checking yourself:
//   
//  $rob = new Redis_OB('my-key');
//  if($rob->cache === false)
//     ... your code ...
//  $rob->output();
class Redis_Cache_OB extends Redis_Cache {

    var $key_prefix = 'Cache_OB';
    function __construct($key,$opts='') {
        parent::__construct($key,$opts);
        $this->profile_start();
        
        if($this->cache_miss)
            ob_start();
    }

    function end() {
        if($this->cache_miss) {
            $this->cache = ob_get_clean();
            $this->write_cache($this->cache);
        }
    }

    function output() {
        $this->end();
        if($this->opts['output_cache'])
            echo $this->cache;
        $this->profile_end();
    }
}

// Makes a one liner out of the caching process
// You can pass through a string with a function name, or an anonymous function
// Optional args array for the called fn
class Redis_Cache_OB_Func extends Redis_Cache_OB {
    function __construct($key,$func,$args=false,$opts='') {
        parent::__construct($key,$opts);
        if($this->cache_miss) {
            if($args !== false && is_array($args))
                call_user_func_array($func,$args);
            else
                call_user_func($func);
        }
        $this->output();
    }
}

// Caching a php variable through serialize()
class Redis_Cache_Var extends Redis_Cache {
    var $key_prefix = 'Cache_Var';
}

// Since we can't delay instantiation of a new object at call time, we have to wrap it in a callback function that returns the new object
// We could do it with new Redis_Cache_Var('key','class_name',array('constructor','params')) but anon fns are more flexible
//
//  Before caching:
//      $my_obj = new MyObj(); 
//  After caching: 
//      $my_obj =  redis_cache_var('my_obj',function(){
//          return new MyObj(); 
//      });
//
function redis_cache_var($key,$cb_func,$opts='') {
    $rcv = new Redis_Cache_Var($key,$opts); 
    $rcv->profile_start();
    if($rcv->cache_hit)
        $obj = unserialize($rcv->cache);
    else {
        $obj = $cb_func();
        $rcv->write_cache(serialize($obj));
    }
    $rcv->profile_end();
    return $obj;
}

// Allows us silent redis errors in case we don't have it
class Fake_Redis {

    // Need to have some way of telling if we're a dirty faker!
    var $is_fake_redis = true;

    // Stubbbbzz
    function connect($a='',$b='',$c='',$d='',$e='') { return false; }
    function pconnect($a='',$b='',$c='',$d='',$e='') { return false; }
    function close($a='',$b='',$c='',$d='',$e='') { return false; }
    function ping($a='',$b='',$c='',$d='',$e='') { return false; }
    function get($a='',$b='',$c='',$d='',$e='') { return false; }
    function set($a='',$b='',$c='',$d='',$e='') { return false; }
    function setex($a='',$b='',$c='',$d='',$e='') { return false; }
    function setnx($a='',$b='',$c='',$d='',$e='') { return false; }
    function getSet($a='',$b='',$c='',$d='',$e='') { return false; }
    function randomKey($a='',$b='',$c='',$d='',$e='') { return false; }
    function renameKey($a='',$b='',$c='',$d='',$e='') { return false; }
    function renameNx($a='',$b='',$c='',$d='',$e='') { return false; }
    function getMultiple($a='',$b='',$c='',$d='',$e='') { return false; }
    function exists($a='',$b='',$c='',$d='',$e='') { return false; }
    function delete($a='',$b='',$c='',$d='',$e='') { return false; }
    function incr($a='',$b='',$c='',$d='',$e='') { return false; }
    function incrBy($a='',$b='',$c='',$d='',$e='') { return false; }
    function decr($a='',$b='',$c='',$d='',$e='') { return false; }
    function decrBy($a='',$b='',$c='',$d='',$e='') { return false; }
    function type($a='',$b='',$c='',$d='',$e='') { return false; }
    function append($a='',$b='',$c='',$d='',$e='') { return false; }
    function getRange($a='',$b='',$c='',$d='',$e='') { return false; }
    function setRange($a='',$b='',$c='',$d='',$e='') { return false; }
    function getBit($a='',$b='',$c='',$d='',$e='') { return false; }
    function setBit($a='',$b='',$c='',$d='',$e='') { return false; }
    function strlen($a='',$b='',$c='',$d='',$e='') { return false; }
    function getKeys($a='',$b='',$c='',$d='',$e='') { return false; }
    function sort($a='',$b='',$c='',$d='',$e='') { return false; }
    function sortAsc($a='',$b='',$c='',$d='',$e='') { return false; }
    function sortAscAlpha($a='',$b='',$c='',$d='',$e='') { return false; }
    function sortDesc($a='',$b='',$c='',$d='',$e='') { return false; }
    function sortDescAlpha($a='',$b='',$c='',$d='',$e='') { return false; }
    function lPush($a='',$b='',$c='',$d='',$e='') { return false; }
    function rPush($a='',$b='',$c='',$d='',$e='') { return false; }
    function lPushx($a='',$b='',$c='',$d='',$e='') { return false; }
    function rPushx($a='',$b='',$c='',$d='',$e='') { return false; }
    function lPop($a='',$b='',$c='',$d='',$e='') { return false; }
    function rPop($a='',$b='',$c='',$d='',$e='') { return false; }
    function blPop($a='',$b='',$c='',$d='',$e='') { return false; }
    function brPop($a='',$b='',$c='',$d='',$e='') { return false; }
    function lSize($a='',$b='',$c='',$d='',$e='') { return false; }
    function lRemove($a='',$b='',$c='',$d='',$e='') { return false; }
    function listTrim($a='',$b='',$c='',$d='',$e='') { return false; }
    function lGet($a='',$b='',$c='',$d='',$e='') { return false; }
    function lGetRange($a='',$b='',$c='',$d='',$e='') { return false; }
    function lSet($a='',$b='',$c='',$d='',$e='') { return false; }
    function lInsert($a='',$b='',$c='',$d='',$e='') { return false; }
    function sAdd($a='',$b='',$c='',$d='',$e='') { return false; }
    function sSize($a='',$b='',$c='',$d='',$e='') { return false; }
    function sRemove($a='',$b='',$c='',$d='',$e='') { return false; }
    function sMove($a='',$b='',$c='',$d='',$e='') { return false; }
    function sPop($a='',$b='',$c='',$d='',$e='') { return false; }
    function sRandMember($a='',$b='',$c='',$d='',$e='') { return false; }
    function sContains($a='',$b='',$c='',$d='',$e='') { return false; }
    function sMembers($a='',$b='',$c='',$d='',$e='') { return false; }
    function sInter($a='',$b='',$c='',$d='',$e='') { return false; }
    function sInterStore($a='',$b='',$c='',$d='',$e='') { return false; }
    function sUnion($a='',$b='',$c='',$d='',$e='') { return false; }
    function sUnionStore($a='',$b='',$c='',$d='',$e='') { return false; }
    function sDiff($a='',$b='',$c='',$d='',$e='') { return false; }
    function sDiffStore($a='',$b='',$c='',$d='',$e='') { return false; }
    function setTimeout($a='',$b='',$c='',$d='',$e='') { return false; }
    function save($a='',$b='',$c='',$d='',$e='') { return false; }
    function bgSave($a='',$b='',$c='',$d='',$e='') { return false; }
    function lastSave($a='',$b='',$c='',$d='',$e='') { return false; }
    function flushDB($a='',$b='',$c='',$d='',$e='') { return false; }
    function flushAll($a='',$b='',$c='',$d='',$e='') { return false; }
    function dbSize($a='',$b='',$c='',$d='',$e='') { return false; }
    function auth($a='',$b='',$c='',$d='',$e='') { return false; }
    function ttl($a='',$b='',$c='',$d='',$e='') { return false; }
    function persist($a='',$b='',$c='',$d='',$e='') { return false; }
    function info($a='',$b='',$c='',$d='',$e='') { return false; }
    function resetStat($a='',$b='',$c='',$d='',$e='') { return false; }
    function select($a='',$b='',$c='',$d='',$e='') { return false; }
    function move($a='',$b='',$c='',$d='',$e='') { return false; }
    function bgrewriteaof($a='',$b='',$c='',$d='',$e='') { return false; }
    function slaveof($a='',$b='',$c='',$d='',$e='') { return false; }
    function object($a='',$b='',$c='',$d='',$e='') { return false; }
    function mset($a='',$b='',$c='',$d='',$e='') { return false; }
    function msetnx($a='',$b='',$c='',$d='',$e='') { return false; }
    function rpoplpush($a='',$b='',$c='',$d='',$e='') { return false; }
    function brpoplpush($a='',$b='',$c='',$d='',$e='') { return false; }
    function zAdd($a='',$b='',$c='',$d='',$e='') { return false; }
    function zDelete($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRange($a='',$b='',$c='',$d='',$e='') { return false; }
    function zReverseRange($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRangeByScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRevRangeByScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zCount($a='',$b='',$c='',$d='',$e='') { return false; }
    function zDeleteRangeByScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zDeleteRangeByRank($a='',$b='',$c='',$d='',$e='') { return false; }
    function zCard($a='',$b='',$c='',$d='',$e='') { return false; }
    function zScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRank($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRevRank($a='',$b='',$c='',$d='',$e='') { return false; }
    function zInter($a='',$b='',$c='',$d='',$e='') { return false; }
    function zUnion($a='',$b='',$c='',$d='',$e='') { return false; }
    function zIncrBy($a='',$b='',$c='',$d='',$e='') { return false; }
    function expireAt($a='',$b='',$c='',$d='',$e='') { return false; }
    function hGet($a='',$b='',$c='',$d='',$e='') { return false; }
    function hSet($a='',$b='',$c='',$d='',$e='') { return false; }
    function hSetNx($a='',$b='',$c='',$d='',$e='') { return false; }
    function hDel($a='',$b='',$c='',$d='',$e='') { return false; }
    function hLen($a='',$b='',$c='',$d='',$e='') { return false; }
    function hKeys($a='',$b='',$c='',$d='',$e='') { return false; }
    function hVals($a='',$b='',$c='',$d='',$e='') { return false; }
    function hGetAll($a='',$b='',$c='',$d='',$e='') { return false; }
    function hExists($a='',$b='',$c='',$d='',$e='') { return false; }
    function hIncrBy($a='',$b='',$c='',$d='',$e='') { return false; }
    function hMset($a='',$b='',$c='',$d='',$e='') { return false; }
    function hMget($a='',$b='',$c='',$d='',$e='') { return false; }
    function multi($a='',$b='',$c='',$d='',$e='') { return false; }
    function discard($a='',$b='',$c='',$d='',$e='') { return false; }
    function exec($a='',$b='',$c='',$d='',$e='') { return false; }
    function pipeline($a='',$b='',$c='',$d='',$e='') { return false; }
    function watch($a='',$b='',$c='',$d='',$e='') { return false; }
    function unwatch($a='',$b='',$c='',$d='',$e='') { return false; }
    function publish($a='',$b='',$c='',$d='',$e='') { return false; }
    function subscribe($a='',$b='',$c='',$d='',$e='') { return false; }
    function unsubscribe($a='',$b='',$c='',$d='',$e='') { return false; }
    function getOption($a='',$b='',$c='',$d='',$e='') { return false; }
    function setOption($a='',$b='',$c='',$d='',$e='') { return false; }
    function open($a='',$b='',$c='',$d='',$e='') { return false; }
    function popen($a='',$b='',$c='',$d='',$e='') { return false; }
    function lLen($a='',$b='',$c='',$d='',$e='') { return false; }
    function sGetMembers($a='',$b='',$c='',$d='',$e='') { return false; }
    function mget($a='',$b='',$c='',$d='',$e='') { return false; }
    function expire($a='',$b='',$c='',$d='',$e='') { return false; }
    function zunionstore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zinterstore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRemove($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRem($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRemoveRangeByScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRemRangeByScore($a='',$b='',$c='',$d='',$e='') { return false; }
    function zRemRangeByRank($a='',$b='',$c='',$d='',$e='') { return false; }
    function zSize($a='',$b='',$c='',$d='',$e='') { return false; }
    function substr($a='',$b='',$c='',$d='',$e='') { return false; }
    function rename($a='',$b='',$c='',$d='',$e='') { return false; }
    function del($a='',$b='',$c='',$d='',$e='') { return false; }
    function keys($a='',$b='',$c='',$d='',$e='') { return false; }
    function lrem($a='',$b='',$c='',$d='',$e='') { return false; }
    function ltrim($a='',$b='',$c='',$d='',$e='') { return false; }
    function lindex($a='',$b='',$c='',$d='',$e='') { return false; }
    function lrange($a='',$b='',$c='',$d='',$e='') { return false; }
    function scard($a='',$b='',$c='',$d='',$e='') { return false; }
    function srem($a='',$b='',$c='',$d='',$e='') { return false; }
    function sismember($a='',$b='',$c='',$d='',$e='') { return false; }
    function zrevrange($a='',$b='',$c='',$d='',$e='') { return false; }
}

?>