The classloader is provided by Nextcloud and loads all your classes automatically. The only thing left to include by yourself are 3rdparty libraries. Those should be loaded in lib/AppInfo/Application.php.

New in version 10.

PSR-4 autoloading

Since Nextcloud 10 there is a PSR-4 autoloader in place. The namespace \OCA\MyApp is mapped to /apps/myapp/lib/. Afterwards normal PSR-4 rules apply, so a folder is a namespace section in the same casing and the class name matches the file name.

If your appid can not be turned into the namespace by uppercasing the first character, you can specify it in your appinfo/info.xml by providing a field called namespace. The required namespace is the one which comes after the top level namespace OCA\, e.g.: for OCA\MyBeautifulApp\Some\OtherClass the needed namespace would be MyBeautifulApp and would be added to the info.xml in the following way:

<?xml version="1.0"?>
   <!-- other options here ... -->

A second PSR-4 root is available when running tests. \OCA\MyApp\Tests is thereby mapped to /apps/myapp/tests/.

Legacy autoloading

The legacy classloader, deprecated since 10, is still in place and works like this:

  • Take the full qualifier of a class:

  • If it starts with \OCA include file from the apps directory

  • Cut off \OCA:

  • Convert all charactes to lowercase:

  • Replace \ with /:

  • Append .php:

  • Prepend /apps because of the OCA namespace and include the file:

    require_once '/apps/myapp/controller/pagecontroller.php';

In other words: In order for the PageController class to be autoloaded, the class \OCA\MyApp\Controller\PageController needs to be stored in the /apps/myapp/controller/pagecontroller.php