In this tutorial you will learn about the CodeIgniter Application Architecture and its application with practical example.
CodeIgniter Application Architecture
The following picture depicts the codeigniter application architecture or request flow for any client request that comes to it –
index.php:- The index.php works as the application front controller, that initializes or load the base resources required for application.
Router:- The Router examines the incoming request and decide what should be done next, whether to pass this request to caching or to pass it to security.
Caching:- If a cache file exists corresponding to incoming request, it is sent directly to the browser, ignoring the further processing.
Security:- Before request is routed to application controller, the request and submitted data is examined for security check.
Application Controller:- The Application Controller loads all of the required Models, Libraries, Helpers, Plugins, Scripts and any other resources required for processing the specific request.
View:- The finalized output is incorporated into View is sent to the web browser. If View is not cached then it will be cached first for subsequent requests.