I'm trying to do a simple CMS with PHP from scratch using MVC structure.

Yesterday I posted this, which is a login system using PHP and it works but it has a handful of problems regarding the OOP aspects of it.

This is kind of the version 2. It doesn't have the login functionality, it's just a "routing system" that will support different request methods and supports dynamic routing (URL parameters and query strings).

This is the project structure:

.
+-- classes
|   +-- Database.php
|   +-- Route.php
+-- controllers
|   +-- AboutUs.php
|   +-- Controller.php
+-- views
|   +-- about-us.php
+-- .htaccess
+-- index.php
+-- routes.php

I'm gonna write here what I have in each file:

Database.php

<?php

class Database{

    public static $host = 'localhost';
    public static $dbName = 'cms';
    public static $username = 'root';
    public static $password = '';

    private static function connect(){
        $pdo = new PDO('mysql:host='.self::$host.';dbname='.self::$dbName.';charset=utf8', self::$username, self::$password);
        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        return $pdo;
    }

    public static function query($query, $params = array()){
        $statement = self::connect()->prepare($query);
        $statement->execute($params);
        if(explode(' ', $query)[0] == 'SELECT'){
            $data = $statement->fetchAll();
            return $data;
        }
    }
}

?>

Route.php - this is where I made the most work

<?php

class Route {
    public static function get($route, $function){
        //get method, don't continue if method is not the 
        $method = $_SERVER['REQUEST_METHOD'];
        if($method !== 'GET'){ return; }

        //check the structure of the url
        $struct = self::checkStructure($route, $_SERVER['REQUEST_URI']);

        //if the requested url matches the one from the route
        //get the url params and run the callback passing the params
        if($struct){
            $params = self::getParams($route, $_SERVER['REQUEST_URI']);
            $function->__invoke($params);

            //prevent checking all other routes
            die();
        }
    }

    public static function urlToArray($url1, $url2){
        //convert route and requested url to an array
        //remove empty values caused by slashes
        //and refresh the indexes of the array
        $a = array_values(array_filter(explode('/', $url1), function($val){ return $val !== ''; }));
        $b = array_values(array_filter(explode('/', $url2), function($val){ return $val !== ''; }));

        //debug mode for development
        if(true) array_shift($b);
        return array($a, $b);
    }

    public static function checkStructure($url1, $url2){
        list($a, $b) = self::urlToArray($url1, $url2);

        //if the sizes of the arrays don't match, their structures don't match either
        if(sizeof($a) !== sizeof($b)){
            return false;
        }

        //for each value from the route
        foreach ($a as $key => $value){

            //if the static values from the url don't match
            // or the dynamic values start with a '?' character
            //their structures don't match
            if($value[0] !== ':' && $value !== $b[$key] || $value[0] === ':' && $b[$key][0] === '?'){
                return false;
            }
        }

        //else, their structures match
        return true;
    }

    public static function getParams($url1, $url2){
        list($a, $b) = self::urlToArray($url1, $url2);

        $params = array('params' => array(), 'query' => array());

        //foreach value from the route
        foreach($a as $key => $value){
            //if it's a dynamic value
            if($value[0] == ':'){
                //get the value from the requested url and throw away the query string (if any)
                $param = explode('?', $b[$key])[0];
                $params['params'][substr($value, 1)] = $param;
            }
        }

        //get the last item from the request url and parse the query string from it (if any)
        $queryString = explode('?', end($b))[1];
        parse_str($queryString, $params['query']);

        return $params;
    }
}

?>

AboutUs.php - This is just a blank class extending the controller, for testing purposes.

<?php

class AboutUs extends Controller{
    
}

?>

Controller.php

<?php

class Controller extends Database{

    public static function CreateView($viewName, $urlParams = null){
        require_once('./views/'.$viewName.'.php');
    }
}

?>

about-us.php - This is the view, has nothing but a heading, just for testing

<h1>About Us</h1>

.htaccess

RewriteEngine On

RewriteRule ^([^/]+)/? index.php?url=$1 [L,QSA]

index.php - Autoloading all the classes and requiring the routes file

<?php

    function loadClasses($class_name){
        $classesPath = './classes/'.$class_name.'.php';
        $controllersPath = './controllers/'.$class_name.'.php';

        if(file_exists($classesPath)){
            require_once($classesPath);
        }else if(file_exists($controllersPath)){
            require_once($controllersPath);
        }   
    }

    spl_autoload_register(loadClasses);

    require_once('routes.php');
?>

routes.php - All the routes will be here

<?php

Route::get('/about-us', function(){
    AboutUs::CreateView('about-us');
});

?>

Basically the routing system works like this.

1. First, it checks the request method, if it matches, it continues to test the structure of the URLs.

The structure of the route I set on the routes.php should match the structure of the route the user is accessing.

2. If this is the case, it parses the requested URL and looks for URL parameters and query strings, using the route URL as a base.

3. Then it invokes the callback function passing the URL parameters with an associative array.

4. Then I use a die() statement to stop executing the code. I made this because when I have multiple routes, it will check for the structure of everyone even if one just matched.

BTW, I have only the GET method right now but then when I add more, I'll probably put this into a function and use that in every request method:

//check the structure of the url
$struct = self::checkStructure($route, $_SERVER['REQUEST_URI']);

//if the requested url matches the one from the route
//get the url params and run the callback passing the params
if($struct){
    $params = self::getParams($route, $_SERVER['REQUEST_URI']);
    $function->__invoke($params);

    //prevent checking all other routes
    die();
}

Examples from the routing:

Routes:

/users/:username
/users/:username/photos
/users/:username/photos/:photoId
/users/:username/photos/:photoId?showComments=false

Requested URLS:

/users/jake1990
/users/jake1990/photos
/users/jake1990/photos/931280134
/users/jake1990/photos/931280134?showComments=false

Callback $urlParams:

Array -> [params => [username => jake1990], query: []];
Array -> [params => [username => jake1990], query: []];
Array -> [params => [username => jake1990, photoId => 931280134], query: []];
Array -> [params => [username => jake1990, photoId => 931280134], query: [showComments => false]];

A few things to point out:

1. I just coded the GET method in the Route class but implementing the other ones (POST, PUT, DELETE) should be easy.
2. I don't know if the code from the routing covers all the cases but I'm trying to achieve that, so if there is a case where it doesn't work and it should, please point it out.
3. If there's any bad practice or antipattern in my code, please tell because I'm striving to follow the best practices to make the code flexible and easy to maintain.
4. It's the first time I do MVC so it's probably full of errors or unnecessary stuff.