Question

So I have an object that reads a file from disk gnugpg it appears to always create a gnugpg key ring in a home directory.

I want to avoid having to load this object every time a php script is called from apache.

is there away to have a php object stay in memory?

Answer 1

If it’s a small object that doesn’t take up much memory and is serializable you could just store it in the session:

function    getSessionObject($objectName, $params){

    $sessionObjectSerialized = getSessionVariable($objectName, FALSE);

    if($sessionObjectSerialized == FALSE){
        $sessionObjectSerialized = constructSessionObject($objectName, $params);
        setSessionVariable($objectName, $sessionObjectSerialized);
    }

    $sessionObject = unserialize($sessionObjectSerialized);

    return $sessionObject;
}


function    constructSessionObject($objectName, $params = array()){

    switch($objectName){

        case('gnugpg_key_ring'):{
            $gnugpgKeyRing = getGNUPGKeyRing(); //do whatever you need to do to make the keyring.
            return serialize($countryScheme);
        }

        default:{
            throw new UnsupportedOperationException("Unknown object name objectName, cannot retrieve from session.");
            break;
        }
    }
}

//Call this before anything else
function initSession(){
    session_name('projectName');
    session_start();
}

function setSessionVariable($name, $value){
    $_SESSION['projectName'][$name] = $value;
}

function getSessionVariable($name, $default = FALSE){

    if(isset($_SESSION['projectName'])){
        if(isset($_SESSION['projectName'][$name])){
            $value = $_SESSION['projectName'][$name];
        }
    }
    return $default;
}

and then retrieve that object by calling

getSessionObject('gnugpg_key_ring');

However not all objects are always serializable e.g. if the object holds a file handle to an open file, that would need to have some extra code to close the file when the object is serialized and then re-open the file when the object was unserialized.

If the object is large, then you would be better off using a proper caching tool like memcached to store the serialized object, rather than the session.