如何将独立的 PHP 文件转换为 Magento 的 MVC

I am including the php file that I need to convert to Magento MVC. So it will be easier for you to understand..

<?php header('content-type: application/json; charset=utf-8');
$link = mysqli_connect("localhost", "db_username", "password", "db_dbname");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s
", mysqli_connect_error());
    exit();
}

$pid = $_REQUEST['prodid'];

/* Select queries return a resultset */

$result = mysqli_query($link, "SELECT round(rating_summary / 20) AS search_rating FROM review_entity_summary where store_id = 1 and entity_pk_value=" . $pid);

// printf("Select returned %d rows.
" . "<br>
", mysqli_num_rows($result)) . "<br>
";
//$string = $_REQUEST['varname'];
    $rows = array();
  /*  while ($row = $result->fetch_row()) {
                printf("%s
", $row[0]);
            }*/
//while($r = mysql_fetch_assoc($result)) {
while ($r = mysqli_fetch_assoc($result)) {
    $rows = $r;
//print_r ($rows) . "<br>
";
}
$json_data = json_encode($rows);
print_r ($json_data);
    /* free result set */
   // mysqli_free_result($result)

mysqli_close($link);
?>

那么我怎样才能把这个文件转换成 Magento 的 MVC 风格呢??是否需要将此文件转换为 magento MVC?

require_once 'path/to/magento'. "/Mage.php";
umask(0);
Mage::app("default");
....

appcodelocalMyNamespace

appcodelocalMyNamespaceAppname

appcodelocalMyNamespaceAppnameBlock

appcodelocalMyNamespaceAppnamecontrollers

appcodelocalMyNamespaceAppname etc

appcodelocalMyNamespaceAppnameHelper

 appcodelocalMyNamespaceAppnameModel

 appcodelocalMyNamespaceAppnamesql

 etcmodules