Using Composer

Even though this is not a necessary component when implementing the MVC pattern, Composer has been an indispensable tool for any PHP web application over the last few years. The main goal of this tool is to help you manage the dependencies of your application, that is, the third-party libraries (of code) that we need to use in our application. We can achieve that by just creating a configuration file that lists them, and by running a command in your command line.

You need to install Composer on your development machine (see Chapter 1, Setting Up the Environment). Make sure that you have it by executing the following command:

$ composer –version

This should return the version of your Composer installation. If it does not, return to the installation section to fix the problem.

Managing dependencies

As we stated earlier, the main goal of Composer is to manage dependencies. For example, we've already implemented our configuration reader, the Config class, but if we knew of someone...