Architecture

PrestaShop v1.6 Architecture

PrestaShop uses Model-View-Controller (MVC) for its software architecture, which is often used in web applications where webpages are dynamically generated. MVC isolates application logic from the input and presentation, so that they can be separately developed, tested and maintained.

A view provides the user interface presented to the customer in the browser. A controller receives input from the browser, decides what to do with it and then passes information to models that carry out specific tasks.

In PrestaShop 1.6, the models are in the classes directory, the views are in the themes directory and the controllers are in the controllers directory. The files in the root directory are the public interface used to call the controllers.

Everything passes through index.php in the root directory to improve sharing of code and make processing friendly URLs easier. There are also index.php files in all subdirectories of PrestaShop, but these are used only to prevent the contents of the directories from being displayed in browsers. Some subdirectories have an .htaccess file too to allow or block access to individual files.

All the models, views and controllers have a warning at the top of them to not modify the file if the website will be upgraded to a new version of PrestaShop in the future. This is because PrestaShop allows these files to be overridden.

Classes and controllers are overridden using the override directory. By overriding classes and controllers instead of modifying them, they can be safely overwritten by a new version of PrestaShop in the future without losing any changes that were made.

PrestaShop's modules also have the same warning, since they can be overridden in a theme by mirroring the module's directory inside the theme, e.g. themes/themename/modules/blockuserinfo/blockuserinfo.tpl.

Models

The models in the classes directory of PrestaShop are all PHP classes that extend the ObjectModel class. This class gives the models a unique ID and a table name and identifier to link them to a row in the database.

For example, in the Address model, the ID is a positive integer, the table name is address and the table identifier is id_address. The ObjectModel class also defines the model's field sizes and the functions in the Validate class that are used to validate fields.

It also links the model to the webservice feature and provides a cache. The model class names all end in Core so they can be overridden in the override/classes directory. Here is a description of each PrestaShop model:

Here's a description of the other PrestaShop classes that do not store data in the database:

Here's a description of the ObjectModel members:

Here's a description of the ObjectModel functions:

Here's a description of the validation functions:

Here's a list of useful static functions available in the Tools class:

Views

PrestaShop uses Smarty templating for its views, which supplements HTML with a flexible syntax to add variables, if statements, loops and other PHP code to the view. Here is a description of PrestaShop's default theme templates:

The following Smarty variables are accessible in all of the templates:

Controllers

Here's a list of PrestaShop's controllers and a description of what each of them do:

All controllers in PrestaShop extend the FrontController class. Here's a description of the FrontController members:

Here's a description of the controller functions in the order they are executed: