试用期系统连同订阅 - PHP 和 MySQL

Question

I built a trial period system using PHP and Mysql and it is working completely fine. But what I'm trying to achieve is that it should automatically update the time period, once the user buys the subscription. For example, if a user signs up for 30 days subscription, then it should increase by 30 days.

I'm not expecting someone to write the code for me. Just want to know how it could be done. Because this is the first time I'm building such a thing. Need your guidance on it!

and I know code is vulnerable to SQL Injection. You can ignore it because this is just for testing purpose

<?php 

session_start();

include 'db-connection.php';

   $user_email = mysqli_real_escape_string($connection, $_POST['user_email']);
   $user_pass = mysqli_real_escape_string($connection, $_POST['user_pass']);
   
   $select_user = "select * from users where user_email='$user_email'";
   $select_user_query = mysqli_query($connection, $select_user);
   $user_email_count = mysqli_num_rows($select_user_query);

   if($user_email_count) {
       $user_result_array = mysqli_fetch_array($select_user_query);
       $user_db_pass = $user_result_array['user_pass'];
       $user_id = $user_result_array['user_id'];
       $user_name = $user_result_array['user_name'];
       
     
       
       if($user_pass === $user_db_pass ) {
           $_SESSION['user_id'] = $user_id;
           $_SESSION['user_name'] = $user_name;
           
       $user_registration_date = new DateTime($user_result_array['user_registration']); // This fetch the user registration date from database
       $today_date = new DateTime();
       $trial_period = 7;
       $date_diff = date_diff($user_registration_date,$today_date);
       $date_difference = $date_diff->format('%d days');
           
           if($date_difference >= $trial_period){
             echo "Trial period is over";
           } else {
             echo "<span class='alert alert-success'>Login Successful</span>";
           }
       
       } else {
           echo "<span class='alert alert-danger'>You have entered wrong password</span>";
       }
       
   } else {
       echo "<span class='alert alert-danger'>No Record Found</span>";
   }

?>

Once the trial period is over, it would redirect the user to the trial.php page where the user would be asked to do the payment.

Once the payment is made, it should increase the time period (this is the step which I don't know how to achieve)

User Table

User_id | user_registration | user_name | user_email | user_pass | user_phone

Answer 1

1. Add expiry_date column in user table (which will be added auto after registration.. like current_date + 30 days . Plus add one more column fees_paid=0 .

2. If you are using payment gateway for payment, then send auto email with payment link to user before trial period expires . If user make payment, update database expiry_date with registartion_date + 60 days (or XX Days, you want to add) and fees_paid=1 alogn with other payment details like payment date, payment_id etc... via webhook response along with payment details.

3. If you are not using payment gateway and collecting payment via neft / cash etc., then via your admin panel, activate user's account by adding desired days in registration_date of user.

In database, you can add some columns like fees_paid = 0 / fees_paid = 1 (0 for not paid and 1 for paid), order_number= random_generated_unique_string , payment_date , payment_id etc for saving payment details.