server.php

<?php
header('Access-Control-Allow-Origin: *');
header('Content-Type: application/json');

if(!isset($_POST)) die();

session_start();

$response = [];

$con = mysqli_connect('localhost', 'root', '', 'vocational training institute');

$username = mysqli_real_escape_string($con, $_POST['username']);
$password = mysqli_real_escape_string($con, $_POST['password']);



$query = "SELECT * FROM `user_tbl` WHERE Username='$username' AND Password='$password'";

$result = mysqli_query($con, $query);
$row = mysqli_fetch_array($result);
if(mysqli_num_rows($result) > 0) {
    $response['status'] = 'loggedin';
    $response['user'] = $username;
    $response['Type'] = $row[3];
    $response['useruniqueid'] = md5(uniqid());
    $_SESSION['useruniqueid'] = $response['useruniqueid'];
}else{
    $response['status'] = 'error';
}


echo json_encode($response);