I am currently learning MVC pattern and I have a problem with understanding how to pass data from controller to model and then from model to view.
My structure looks like this
/controllers
index.php
/libs
controller.php
main.php
view.php
/models
index_model.php
/views
index.php
.htaccess
index.php
First I always create an main object and include files that i need
include 'libs/Main.php';
require 'libs/Controller.php';
require 'libs/view.php';
$main = new Main();
then in main class i reroute the url so correct controller is called
class Main {
public function __construct() {
$url = (isset($_GET['url']) ? $_GET['url'] : null);
$url = rtrim($url, '/');
$url = explode('/', $url);
if(empty($url[0])){
require'controllers/index.php';
$controller = new Index();
}else{
$file = 'controllers/'. $url[0] .'.php';
if(file_exists($file)){
require $file;
} else
die("Error");
}
}
}
This is the controller for index page
class Index extends Controller{
public function __construct() {
parent::__construct(); //Creates new view object from parents class
$this->model = parent::loadModel('index');
//there should probably exists some method that will pass the data to model
$this->view->render('index'); //renders view, but also it should have another argument that contains data, i think
if(isset($_POST['SubmitCosmonautForm'])){
var_dump($_POST);
}
}
}
This is main controller that every other controller will inherit, so all have created view object
class Controller {
public function __construct(){
$this->view = new view();
}
protected function loadModel($name){
$path = 'models/'.$name.'_model.php';
if(file_exists($path)){
require $path;
$modelName = $name.'_model';
$this->model = new modelName();
}else{
echo "Model for" .$name."doesn't exists";
}
}
}
and this is the view in library, which contains render function so far
class View{
public function render($name){
require 'views/' .$name. '.php';
}
}
For example i want to save form data to database, so when i am thinking about it i should probably pass only data to model, and inside that model i should call methods that will handle saving/loading/changing DB, these methods that operates over DB could be in database class. Is this the right approach ? i read about mvc last 2 hours but i don't know if i understand it correctly.
Related
I am trying to build a loader to load various controller with their methods (as needed) within a controller. I sketched out a simple code on my home controller to call the LeftController (now a dummy controller but I intend to use this controller as menu).
require 'controller/LeftController.php';
$LeftController = new LeftController();
$LeftController->index();
This works within the HomeController. It loads the LeftController controller and displays the method index().
Basing my Loader on the above code this is what I have done till now
class Loader
{
public function controller($controller)
{
$file = 'controller/' . $controller . '.php';
$class = $controller;
if (file_exists($file)) {
require($file); // require 'controller/LeftController.php';
$controller = new $class(); //$LeftController = new LeftController();
var_dump($controller);
}
}
}
This works too and the controller is instantiated. I see result using the var_dump().
Now, I need to call the method, as we see at the top most code $LeftController->index(); but on the Loader class this time.
One way of doing this is if I add $controller->index() right after the $controller = new $class(); but this will always call the index() method of the controller.
How do I code this method part as such that I can call any method associated with the controller and not just the index().
You can pass a method argument with your controller:
public function controller($controller, $method)
and then call it on your newly created object:
$controller->$method()
However,
it seems you are trying to reinvent the wheel. The part where you verify if a files exists, include it and instantiate the class, is called autoloading.
The code could look like this:
public function controller($controller, $method)
{
$instance = new $controller();
return $instance->$method();
}
While the autoloading part makes use of spl_autoload_register() to manage finding and including files.
The spl_autoload_register() function registers any number of autoloaders, enabling for classes and interfaces to be automatically loaded if they are currently not defined.
So you can use the code you already have, and abstract it from the action of instantiating the class:
spl_autoload_register(function autoloader($controller) {
$file = 'controller/' . $controller . '.php';
if (file_exists($file)) { require($file); }
});
I've done quite a bit of reading on this and a lot of people are saying I should be using a singleton class. I was thinking of writing a "Config" class which would include a "config.php" file on __construct and loop through the $config array values and place them into $this->values...
But then I read more and more about how singletons should never be used. So my question is - what is the best approach for this? I want to have a configuration file, for organization purposes, that contains all of my $config variables. I do not want to be hardcoding things such as database usernames and passwords directly into methods, for the purpose of flexibility and whatnot.
For example, I use the following code in an MVC project I am working on:
public/index.php
<?php
include '../app/bootstrap.php';
?>
app/bootstrap.php
<?php
session_start();
function __autoload ($class) {
$file = '../app/'.str_replace('_', '/', strtolower($class)).'.php';
if (file_exists($file)) {
include $file;
}
else {
die($file.' not found');
}
}
$router = new lib_router();
?>
app/lib/router.php
<?php
class lib_router {
private $controller = 'controller_home'; // default controller
private $method = 'index'; // default method
private $params = array();
public function __construct () {
$this->getUrl()->route();
}
private function getUrl () {
if (isset($_GET['url'])) {
$url = trim($_GET['url'], '/');
$url = filter_var($url, FILTER_SANITIZE_URL);
$url = explode('/', $url);
$this->controller = isset($url[0]) ? 'controller_'.ucwords($url[0]) : $this->controller;
$this->method = isset($url[1]) ? $url[1] : $this->method;
unset($url[0], $url[1]);
$this->params = array_values($url);
}
return $this;
}
public function route () {
if (class_exists($this->controller)) {
if (method_exists($this->controller, $this->method)) {
call_user_func(array(new $this->controller, $this->method), $this->params);
}
else {
die('Method '.$this->method.' does not exist');
}
}
else {
die('Class '.$this->controller.' does not exist');
}
}
}
?>
Now let's say I visit http://localhost/myproject/lead/test
It is going to call the controller_lead class and the test method within.
Here is the code for app/controller/lead
<?php
class controller_lead extends controller_base {
public function test ($params) {
echo "lead test works!";
}
}
?>
app/controller/base
<?php
class controller_base {
private $db;
private $model;
public function __construct () {
$this->connect()->getModel();
}
private function connect () {
//$this->db = new PDO($config['db_type'] . ':host=' . $config['db_host'] . ';dbname=' . $config['db_name']. ', $config['db_user'], $config['db_pass'], $options);
return $this;
}
private function getModel () {
$model = str_replace('controller', 'model', get_class($this));
$this->model = new $model($this->db);
}
}
?>
This is where I run into the issue. As you can see, the connect method is going to try and create a new PDO object. Now how am I going to inject this $config variable, given all the other code I just provided?
My options appear to be:
Use a singleton (bad)
Use a global (worse)
Include config.php in bootstrap.php, and inject it throughout multiple classes (Why should I inject this into my lib_router class when lib_router has absolutely nothing to do with the database? This sounds like terrible practice.)
What other option do I have? I don't want to do any of those 3 things...
Any help would be greatly appreciated.
I ended up including a config file in my bootstrap which simply contained constants, and used the constants.
I ended up including a config file in my bootstrap which simply contained constants, and used the constants.
That was the same case for me - required the file in Model. The file based approach was the best fit since it has some benefits: you can .gitignore, set custom permission set, all your parameters are stored centrally, etc.
However, If the config file contains DB connection parameters only, I prefered to require the config file in Model only. Maybe, you could also break down into multiple, more specific config files and require them where necessary.
public function __construct()
{
if (self::$handle === FALSE)
{
$db = array();
require APP_DIR.DIR_SEP.'system'.DIR_SEP.'config'.DIR_SEP.'Database.php';
if (!empty($db))
{
$this->connect($db['db_host'], $db['db_user'], $db['db_password'], $db['db_name']);
}
else
{
Error::throw_error('Abimo Model : No database config found');
}
}
}
My question is how to dynamically include and call the model and view classes in a simple MVC model? I have no problem calling the controller, I have found various ways to do that, but I can't find a good solution for calling and passing in the model and view.
I have setup a .htaccess file to read the url as "www.domain.com/controller/method/id".
I was previously trying to do a check if a file exists for the model and view the same way I am doing the controller using the $cont variable, and then trying to load the model and pass it into the controller, then the view. The issue I had is that all the includes are using the $cont variable to call instantiate their classes and could not tell each other apart. I tried adding a suffic $cont . 'Controller', but then I couldn't load the class at all, let alone pass in the model or view.
Here is my latest example without model or view.
<?php
//===============================================
// Debug
//===============================================
ini_set('display_errors','On');
error_reporting(E_ALL);
//===============================================
// Includes
//===============================================
require('coremvc.php');
//===============================================
// Constants & Globals
//===============================================
define('BASE_PATH', dirname(realpath(__FILE__)));
$GLOBALS['var'] = "";
//===============================================
// Session
//===============================================
session_start();
//===============================================
// Router
//===============================================
if ($_SERVER['REQUEST_URI'] !== '/') {
$uri = $_SERVER['REQUEST_URI'];
$uri = ltrim($uri, '/');
$request = explode('/', $uri);
foreach ($request as $key => $val) {
if(empty($request[$key])) {
unset($request[$key]);
}
}
$request = array_values($request);
if (isset($request[0])) {
$cont = $request[0];
}
if (isset($request[1])) {
$action = $request[1];
}
} else {
$cont = "home";
}
if (FILE_EXISTS('/controllers/' . $cont . 'Controller.php')) {
require '/controllers/' . $cont . 'Controller.php';
} else {
$cont = "home";
require '/controllers/homeController.php';
}
//===============================================
// Start the controller
//===============================================
$controller = new $cont;
I have made the following changes to the example above, posted it below, as well as my super easy bake oven simple controller.
<?php
if (FILE_EXISTS('/controllers/' . $cont . 'Controller.php')) {
require '/controllers/' . $cont . 'Controller.php';
} else {
$cont = "home";
$cont = ucfirst($cont) . 'Controller';
require '/controllers/homeController.php';
}
//===============================================
// Start the controller
//===============================================
$controller = new $cont('World');
$controller->world();
Controller, it is just extending an empty class which I was thinking I could use if I wanted to extend a common method to every class. That is what the coremvc.php is in the index.php above.
<?php
Class HomeController extends Controller
{
function __construct($world) {
echo "Hello ";
$this->world = $world;
}
function world() {
echo $this->world;
}
}
You want to load and call classes easily. I dynamically load classes that end in ".class.php". This makes things easy for me.
I put this in my index.php... where /app/ is where I have my php classes:
<?php
define('CLASS_DIR', '/app/');
set_include_path(get_include_path() . PATH_SEPARATOR . dirname(__FILE__) . CLASS_DIR);
spl_autoload_extensions('.class.php');
spl_autoload_register();
Next, I require my routes:
require 'rte/myroute.php';
I let my routes (controllers) direct my traffic to my models, albeit some parsing, etc.
I typically develop REST based APIs in PHP, so the "view" is just a JSON response.
The HTML / JavaScript client consumes the responses.
A good framework that I like is SlimPHP. I load it up using Composer.
http://www.slimframework.com/
https://getcomposer.org/
Here's an example of calling a class as an instance and statically, since you auto-loaded, you don't need to include anything at the top:
<?php
$param1 = 1;
$param2 = 2;
MyClass::myFunc($param1);
$myObj = new MyClass;
$myObj->myFunc2($param2);
As it is already say you can have a look to use the spl_autoload_register which will require all your files in the given path. You can change this function to improve the load.
Concerning the Model with your current code you can implement it as follow:
$controllerPath = "/controllers/{$cont}Controller.php";
$modelPath = "/model/{$cont}Model.php";
if (FILE_EXISTS($controllerPath)) {
require $controllerPath;
if (FILE_EXISTS($modelPath)) {
require $modelPath;
}
else {
throw new \LogicException(
sprintf("Your controller must implement a model. No model found: %s", $modelPath)
);
}
} else {
$cont = "home";
require "/controllers/{$cont}Controller.php";
require "/model/{$cont}Model.php";
}
//===============================================
// Start the controller
//===============================================
$controller = new $cont($cont);
In this sample of code, $cont is the name of the page like home. Which require the homeController and homeModel. Then in your __construct($modelName) just set the model.
However, I don't recommand you tu use this because your controller can load many Models. Then, your controller could look like this:
<?php
namespace \App\Controller; // If you use namespace
use App\Model\homeModel, // If you use namespace
App\Model\productModel; // If you use namespace
Class HomeController extends Controller
{
private $model;
/* If this function is common to all controllers just move it
in the parent Controller class( one more time, I don't recommend to set
the model using this way). */
public function __construct($model) {
$this->model= $model;
}
public function login() {
$homeModel = new homeModel(); // If you use namespace
// Example to call the view
$myValue = 'Hello world';
$this->render(array("myVariableName" => $myValue))
}
}
In this second example $this->render can be a method in your Controller class (which by the way should be an abstract class). I'll give a last sample of code for the logic of the abstract controller.
<?php
namespace \App\Controller;
abstract class AbstractController {
/* Common code for all controllers */
public function __construct() {
}
/* View renderer */
protected function render($parameters) {
/* Call the view here maybe an another class which manage the View*/
}
}
To conclude, you can implement this MVC in many way, this code is just a suggestion and maybe its not the best way. I advise you to have a look with the spl_autoload that I put at the beginning of my answer.
I'm trying to build a CMS using the MVC pattern. The structure of my CMS is as follows:
->index.php: entry point. Contains the appropriate includes and creates the frontController which takes a router as it's parameter:
$frontController = new FrontController(new Router);
echo $frontController->output();
->router.php: analyses the URL and defines what the names of each Model,View and Controller will be. By default they are preceded by home, but if the url is of the form http://localhost/index.php?route=Register the MVC classes will be named RegisterModel, RegisterView and Register Controller.
if(isset ( $_GET ['route'] ))
{
$this->URL = explode ( "/", $_GET ['route'] );
$this->route = $_GET ['route'];
$this->model = ucfirst($this->URL [0] . "Model");
$this->view = ucfirst($this->URL [0] . "View");
$this->controller = ucfirst($this->URL [0] . "Controller");
}
else
{
$this->model = "HomeModel";
$this->view = "HomeView";
$this->controller = "HomeController";
$this->route = "Home";
}
->frontController.php: This is where I am stuck. When I go to the homepage, it can be visualised correctly because I already have the default HomeModel,HomeView and HomeController classes created. But I created a link that points to register (localhost/index.php?route=Register) but the PHP log indicates that the appropriate Register classes weren't created by the frontController class.
class FrontController
{
private $controller;
private $view;
public function __construct(Router $router)
{
$modelName = $router->model;
$controllerName = $router->controller;
$viewName = $router->view;
$model = new $modelName ();
$this->controller = new $controllerName ( $model );
$this->view = new $viewName ( $router->getRoute(), $model );
if (! empty ( $_GET['action'] ))
$this->controller->{$_GET['action']} ();
}
public function output()
{
// This allows for some consistent layout generation code
return $this->view->output ();
}
}
At this moment I have no idea how to go about solving this issue. And even if I get the classes to be created in the frontController, is there a way to specify that the classes being dynamically generated should extend from a base Model,View,Controller class?
The default HomeView.php looks like this:
class HomeView
{
private $model;
private $route;
private $view_file;
public function __construct($route, HomeModel $model)
{
$this->view_file = "View/" . $route . "/template.php";
echo $this->view_file;
$this->route = $route;
$this->model = $model;
}
public function output()
{
require($this->view_file);
}
}
Any indications on anything that might help me get unstuck or a pointer in the right direction would be much appreciated.
EDIT1:
I forgot to add a summary of my two issues:
1. I would like to understand why the classes aren't being created in the FrontController class...
2. Once created how would I access those classes? Answer is in the comment section. Using the PHP spl_autoload_register function.
Thanks All!
I'm creating an mvc structure for learning/teaching purpouses and so far I could set up the structure and a controller plus twig as template system.
The structure is:
index.php
controllers/
error.php
inc/
controller_base.php
view_manager.php
views/
.cache/
error/
view.html
So:
index instantiate twig autoloader (and mvc autoloader by spl_register).
index instantiate error controller inheriting controller_base.
controller_base is holding the view_manager.
error call view_manager to display the error/view.html and the only thing I get on the browser is error/view.html.
No errors on the apache log. (error_reporting(E_ALL))
Twig cache files created correctly, but the content doesn't look good to me:
protected function doDisplay(array $context, array $blocks = array()) {
// line 1
echo "error/view.html";
}
Anyone knows why, and how can I print the actual view?
Thanks in advance.
Code:
index.php: Declaring autoloaders
function __autoload($class_name)
{
if(file_exists("controllers/$class_name.php")):
include strtolower("controllers/$class_name.php");
elseif(file_exists("models/$class_name.php")):
include strtolower("models/$class_name.php");
elseif(file_exists("inc/$class_name.php")):
include strtolower("inc/$class_name.php");
endif;
}
spl_autoload_register('__autoload');
require_once 'vendor/autoload.php';
Twig_Autoloader::register(); has been avoided cause Twig installation was done by composer.
Adding it doesn't bring any change.
error.php (controller): called method.
public function show($param)
{
$this->viewMng->display(get_class().$data['view'], array())
}
controller_base.php:
class base
{
protected $viewMng;
public function __construct()
{
$this->viewMng = new viewmanager();
}
}
viewmanager.php: whole class
class viewmanager {
private $twig;
protected $template_dir = 'views/';
protected $cache_dir = 'views/.cache';
// protected $vars = array();
public function __construct($template_dir = null) {
if ($template_dir !== null) {
// Check here whether this directory really exists
$this->template_dir = $template_dir;
}
$loader = new Twig_Loader_String($this->template_dir);
$this->twig = new Twig_Environment($loader, array(
'cache' => $this->cache_dir));
}
public function render($template_file, $data = array()) {
if (!file_exists($this->template_dir.$template_file)) {
throw new Exception('no template file ' . $template_file . ' present in directory ' . $this->template_dir);
}
return $this->twig->render($template_file, $data);
}
public function display($template_file, $data) {
if (!file_exists($this->template_dir.$template_file)) {
throw new Exception('no template file ' . $template_file . ' present in directory ' . $this->template_dir);
}
$tmpl = ($this->twig->loadTemplate($template_file));//print_r($tmpl);
$tmpl->display($data);
}
}
view.html:
<html><body> Hello </body></html>
The problem is based on the loader.
According to the Twig documentation:
Twig_Loader_String loads templates from strings. It's a dummy loader
as the template reference is the template source code This
loader should only be used for unit testing as it has severe
limitations: several tags, like extends or include do not make sense
to use as the reference to the template is the template source code
itself.
That's why it only prints the passed in string.
Twig_Loader_String, should be replaced by the proper loader.
In this case it works perfectly well Twig_Loader_Filesystem.
$loader = new Twig_Loader_Filesystem($this->template_dir);
This solve the problem and the MVC structure works completely fine.
Thanks taking a look, guys.