Error controller class. Extends Controller class which is doesn't have authentication/authorization behavior but can be executed directly. The class represents full page load and ajax methods to work with Error class instances and implements methodology of thin controller. Please, implement all business logic code the appropriate service classes.
Located at controllers/error.php
Constructor initializes services properties to manipulate with business logic. Those instances of service objects are created automatically by core logic and passed to the constructor by using the hints. If you want to add another services to you controller just add appropriate property and variable with class hint to the constructor definition. Be sure that you keep all business logic inside service classes in order to better supporting development process and testing.
Page: Handles the error page as partial view that will be shown when a page is not found. Method URL: Will be executed in specific page context. It means that original URL will be kept.