Switch vs Classes for flow control in PHP

Question

Recently, I wrote a simple web application. I currently have.

• A static page which serves the html markup and the resources I need
• A javascript routing handling mechanism which communicate with the server and render responses on the client.

For each object I need to manipulate, the server provides a php script at /app/object.php which accepts POST data and return JSON results.

Eg (not actual responses):

POST /app/comments.php?a=add&page_id=43&author=A&text=Some%20Text
{"s":"OK"}

POST /app/comments.php?a=list&page_id=43
[{ "author": 'A', "text": "Some text"}, { "author": "B", "text": "Other text"}]

POST /app/users.php?a=list
["A", "B", "C"]

Under the hood the JSON api is implemented like that:

//comments.php
require('init.php'); 
// start sessions, open database connections with data in config.php

switch(POST('a')){
case "list":
    //.... retrieving data
    echo json_encode($data)
break;
case "add":
    //.... inserting data
    echo '{"s":"OK"}';
break;
}

The largest object has 7 methods and 200 (well-indented, not compressed) LOC, while the average is roughly 3 methods per object.

A developer friend of mine is suggesting to replace the switch with objects, to make it "simpler", "more extensible" and "more maintainable".

I frankly don't see how a system like that could get any simpler (especially by using objects) but I'd love to know other developers' opinions.

Ignoring the performance hit of using objects in PHP, should I use a class-based approach?

If yes, how can I structure my JSON API in order to use objects, without adding too much code (and thus decreasing the maintainability of the project)?

Answer 1

<?php

class Controller {
  protected $post;
  public function __construct() {
     $this->post = $post;
  }
  public function __call($name, $arguments) {
    if(!method_exists($this, $name)) {
      die("Unknown action!");
    }
  }
  public function whatever() {
    echo json_encode($this->post['page_id']);
  }
  public function data() {
    echo '{"s":"OK"}';
  }
  // new action? just add another method
}


$controller = new Controller();
$controller->{$_POST('a')}(); // example 1

$controller->data(); // you can't do it using switch

1. Easy to add new methods
2. Easy to maintance
3. You can fire your methods whenever your want
4. Code is tidy
5. It's really common practice