How to Make Global Variables like $modx

I am trying to create a general global object variable like '$modx' so I don't have to create new instances in snippets. I am having trouble finding where to place it. I tried making a plugin that fires certain events like onhandlerequest and onpageinit but it still cannot be accessed. I tried creating an instance of the object in the index.php file as I see that is where $modx instance is created, but same result and I cannot access this object.

Any suggestions on how to create global variables/ object variables that can be accessed throughout the application/site without the constant instantiation?

The usual method is to create a new System Setting and use one of these methods to get it:

in PHP:



Or in HTML:


You could also just use a file and either 'include' it or read it.

Thanks for the response BobRay,

I do agree with those options. But, I am looking to access the object without using modx->getOption() or modx tags.

I mainly will be using the object in snippets.

So for example we can access $modx throughout all pages without the necessity of putting



I would like that same convenience for this variable like so:

The problem is that you have to instantiate your object on every page load.

You can add your object to $modx:

$modx->app = $app;


Then refer to it anywhere:

$modx->app;

The nice thing about System Settings is that they're in the DB, so $modx->getOption() can get them anywhere $modx exists with no extra work.

If the objects can be persistent classes, you can create them as packages and use (IIRC) $modx->addExtensionPackage() just once to register them. After that, they'll be stored and the package will be loaded automatically on every page load and you can use something like:



I believe Articles does this. I know ClassExtender does.

If you use $modx->getService, your object is stored in $modx->servicename so it's available where-ever MODX is. You could call getService in a plugin OnHandleRequest and it should be available anywhere after that.

$modx->addExtensionPackages like Bob said is also useful, that could replace the call to getService in a plugin as the extension package is automatically loaded when MODX is instantiated. From memory I'm not sure if that also adds it as $modx->servicename though..

As for $modx being a "global" variable.. it isn't actually a global in the php-global-way most of the time, it just gets passed around in elements and events.