bcit-ci/CodeIgniter

###################
Running via the CLI
###################

As well as calling an applications :doc:`Controllers <./controllers>`
via the URL in a browser they can also be loaded via the command-line
interface (CLI).

.. contents:: Page Contents

What is the CLI?
================

The command-line interface is a text-based method of interacting with
computers. For more information, check the `Wikipedia
article <https://en.wikipedia.org/wiki/Command-line_interface>`_.

Why run via the command-line?
=============================

There are many reasons for running CodeIgniter from the command-line,
but they are not always obvious.

-  Run your cron-jobs without needing to use *wget* or *curl*
-  Make your cron-jobs inaccessible from being loaded in the URL by
   checking the return value of :php:func:`is_cli()`.
-  Make interactive "tasks" that can do things like set permissions,
   prune cache folders, run backups, etc.
-  Integrate with other applications in other languages. For example, a
   random C++ script could call one command and run code in your models!

Let's try it: Hello World!
==========================

Let's create a simple controller so you can see it in action. Using your
text editor, create a file called Tools.php, and put the following code
in it::

    <?php
    class Tools extends CI_Controller {

        public function message($to = 'World')
        {
            echo "Hello {$to}!".PHP_EOL;
        }
    }

Then save the file to your *application/controllers/* folder.

Now normally you would visit the site using a URL similar to this::

    example.com/index.php/tools/message/to

Instead, we are going to open the terminal in Mac/Linux or go to Run > "cmd"
in Windows and navigate to our CodeIgniter project.

.. code-block:: bash

    $ cd /path/to/project;
    $ php index.php tools message

If you did it right, you should see *Hello World!* printed.

.. code-block:: bash

    $ php index.php tools message "John Smith"

Here we are passing it an argument in the same way that URL parameters
work. "John Smith" is passed as an argument and the output is::

    Hello John Smith!

That's it!
==========

That, in a nutshell, is all there is to know about controllers on the
command line. Remember that this is just a normal controller, so routing
and ``_remap()`` works fine.