File hierarchy
==============

We now have a freshly installed Vitya application template. A bunch of directories and files
have been created during the installation process. Your ``my-new-project/`` directory should
look like this::

    |
    +-- cli/
    |   |
    |   +-- post-create-project/
    |   +-- router.php
    |   +-- server
    |   +-- server.php
    |   +-- vitya
    |   +-- vitya.php
    |
    +-- private/
    |   |
    |   +-- app/
    |   |   |
    |   |   +-- config/
    |   |   +-- src/
    |   |   +-- views/
    |   |   +-- bootstrap.php
    |   |   +-- routes.json
    |   |
    |   +-- cache/
    |   +-- data/
    |   +-- log/
    |   +-- sessions/
    |   +-- tmp/
    |
    +-- web/
    |   |
    |    +-- index.php
    |
    +-- .gitignore
    +-- composer.json
    +-- composer.lock

That's a lot of stuff! Let's explore the top level first:

* ``cli/`` mostly contains executable files. As you probably guessed, this is where you'll find all
  the command line utilities, such as the ``server`` command which you have just used to start the built-in web server. 

* ``private/`` contains... well, basically, your whole application. All your classes, controllers, views, PHP dependencies, config files
  will sit somewhere inside this directory.

* ``web/`` is the web root directory. This is the location you'll pass to the ``root`` directive in your Nginx config file,
  or the ``DirectoryRoot`` directive if you use Apache. It contains ``index.php``, aka the front controller, aka the script 
  to which every URL must be redirected.

* The ``.gitignore`` file specifies which files can be ignored when versioning your application. So, once your application template
  is installed, just type ``git init`` and relax. We tried to make the versioning process as effortless as possible. 
  Everything that needs to be present in your repository will be there, and the rest
  will be excluded.

* The ``composer.json`` and ``composer.lock`` files are used by the composer utility to describe all your application dependencies.



``cli/`` (the command line stuff)
---------------------------------

* ``cli/post-create-project/`` is only used by composer during the installation process. In fact, you can
  safely delete this directory once the installation is completed.

* The ``server`` command will start the built-in web server. It requires the ``server.php`` and ``router.php`` files to work properly.

* ``vitya`` is the main utility command. Don't worry too much about it now, we shall see how to use it really soon!



``private/`` (99% of your app probably reside here)
---------------------------------------------------

The ``private/`` directory really contains most of the files that compose your application. This could be 
a good way to think about the top-level directories:

* ``private/`` **is** the application.
* ``cli/`` is an entry point when using the application with the command line.
* ``web/`` is an entry point when using the application with a web browser.



``app/``
^^^^^^^^^^^^^^^^

This is where your own code will reside. As a rule of thumb, if you find yourself writing code outside of this directory, you
are probably doing something wrong.

* ``config/``: your config files. Yup.

* ``src/``: your PHP classes. Your mdels and controllers will go there. 

* ``views/``: your views (probably Twig templates).

* ``bootstrap.php``: this file will instantiate and return a ``Vitya\Application\Application`` object, 
  the service container that constitutes the very heart of your application.

* ``routes.json``: a file describing the routes of your application.



``cache/``, ``data/``, ``log/``, ``sessions/``, ``tmp/``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

You can probably guess what these are used for. Later in this tutorial, we'll explain
more precisely how they work.




``web/`` (the entry point for your web server) 
----------------------------------------------

Your web server (Nginx, Apache or the built-in server) will use this as a root directory.  In other words,
you can put there static assets such as images or CSS files, and they will be served directly by the web server.

It also contains the essential ``index.php`` file. Every URL that do not correspond to a static file should be
redirected to this script so that it's handled by Vitya.