Magento 2 Base Directories

I’m using Magento 2.0.7 as I write this article and I’d like to share something I needed to implement today in one of my projects: retrieving base directories.

The process is pretty straigthforward:

$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$dir = $objectManager->get('\Magento\Framework\App\Filesystem\DirectoryList');
// let's get the log dir for instance
$logDir = $dir->getPath(DirectoryList::LOG);

// this prints "/MAGENTO_ABSOLUTE_PATH_DIR/var/log"
echo $logDir;

Other options are:

   /**
     * Code base root
     */
    const ROOT = 'base';

    /**
     * Most of entire application
     */
    const APP = 'app';

    /**
     * Initial configuration of the application
     */
    const CONFIG = 'etc';

    /**
     * Libraries or third-party components
     */
    const LIB_INTERNAL = 'lib_internal';

    /**
     * Libraries/components that need to be accessible publicly through web-server (such as various DHTML components)
     */
    const LIB_WEB = 'lib_web';

    /**
     * \Directory within document root of a web-server to access static view files publicly
     */
    const PUB = 'pub';

    /**
     * Storage of files entered or generated by the end-user
     */
    const MEDIA = 'media';

    /**
     * Storage of static view files that are needed on HTML-pages, emails or similar content
     */
    const STATIC_VIEW = 'static';

    /**
     * Various files generated by the system in runtime
     */
    const VAR_DIR = 'var';

    /**
     * Temporary files
     */
    const TMP = 'tmp';

    /**
     * File system caching directory (if file system caching is used)
     */
    const CACHE = 'cache';

    /**
     * Logs of system messages and errors
     */
    const LOG = 'log';

    /**
     * File system session directory (if file system session storage is used)
     */
    const SESSION = 'session';

    /**
     * Directory for Setup application
     */
    const SETUP = 'setup';

    /**
     * Dependency injection related file directory
     */
    const DI = 'di';

    /**
     * Relative directory key for generated code
     */
    const GENERATION = 'generation';

    /**
     * Temporary directory for uploading files by end-user
     */
    const UPLOAD = 'upload';

    /**
     * Directory to store composer related files (config, cache etc.) in case if composer runs by Magento Application
     */
    const COMPOSER_HOME = 'composer_home';

Happy Coding!

courtesy: https://blog.mdnsolutions.com/magento-2-base-directories/