Creating Your Own Flash Scope

/**
*********************************************************************************
* Copyright Since 2005 ColdBox Framework by Luis Majano and Ortus Solutions, Corp
* www.coldbox.org | www.luismajano.com | www.ortussolutions.com
********************************************************************************
* This flash scope is smart enough to not create unecessary session variables
* unless data is put in it.  Else, it does not abuse session.
* @author Luis Majano <lmajano@ortussolutions.com>
*/
component extends="coldbox.system.web.flash.AbstractFlashScope" accessors="true"{

    // The flash key
    property name="flashKey";

    /**
    * Constructor
    * @controller.hint ColdBox Controller
    * @defaults.hint Default flash data packet for the flash RAM object=[scope,properties,inflateToRC,inflateToPRC,autoPurge,autoSave]
    */
    function init( required controller, required struct defaults={} ){
        super.init( argumentCollection=arguments );

        variables.flashKey = "cbox_flash_scope";

        return this;
    }

    /**
    * Save the flash storage in preparing to go to the next request
    * @return SessionFlash
    */
    function saveFlash(){
        lock scope="session" type="exclusive" throwontimeout="true" timeout="20"{
            session[ variables.flashKey ] = getScope();
        }
        return this;
    }

    /**
    * Checks if the flash storage exists and IT HAS DATA to inflate.
    */
    boolean function flashExists(){
        // Check if session is defined first
        if( NOT isDefined( "session" ) ) { return false; }
        // Check if storage is set and not empty
        return ( structKeyExists( session, getFlashKey() ) AND NOT structIsEmpty( session[ getFlashKey() ] ) );
    }

    /**
    * Get the flash storage structure to inflate it.
    */
    struct function getFlash(){
        if( flashExists() ){
            lock scope="session" type="readonly" throwontimeout="true" timeout="20"{
                return session[ variables.flashKey ];
            }
        }

        return {};
    }

    /**
    * Remove the entire flash storage
    * @return SessionFlash
    */
    function removeFlash(){
        lock scope="session" type="exclusive" throwontimeout="true" timeout="20"{
             structDelete( session, getFlashKey() );
        }
        return this;
    }

}