how to organize testing of classes with HTTP-requests

I have a concrete task to organize testing of my php-classes' methods using HTTP-requests in Python (function's parameters I get with $_POST).

For example, I have two classes:

File A.php:

class A {
    public function a(array $params) {
        return "Class A params:<br><pre>".print_r($params, TRUE)."</pre>";
    }
}

File B.php:

class B {
    public function b(string $param) {
        return "Class b: $param";
    }
}

My idea is to create directory test with the file structure:

|     index.php
|     style.css
|
|-----classA
|          index.php
|
|-----classB
|          index.php

I think to send python HTTP-requests to main index.php where I search for parameters and then do something like:

if ( isset($_POST['classA']['method_a']) ) {
    $a_obj = new A();
    $params = $_POST['classA']['method_a'];
    $a_obj->a($params);
}

if ( isset($_POST['classB']['method_b']) ) {
    $b_obj = new B();
    $param = $_POST['classB']['method_b'];
    $b_obj->b($param);
}

So, my question. I think my idea is not correct beacuse it seems strange, does it? Also I thought to create no index-file in test root but send request for special folder (like classA/classB folders above). But in that case I get a lot of URLs (it's not very well), so I don't know what to do. I'm confused.

Can somebody advise me a decision?