John Davidson

Message:

I am building a website which requires users to purchase an access code to view a particular web page. I want to restrict the user from using one access code across multiple devices at the same time. One access code should be used on one device and one browser tab at a time. I have already tried to restrict this by storing a flag in database using ajax call when the access code is being used. It sets the flag to 1 when it is accessed and changes the flag to 0 when it detects the tab being closed using the javascript onbeforeunload and onunload functions. But these functions are not reliable as they do not trigger on multiple occasions and the flag remains 1 even after closing the tab. I can't seem to think of any other method to restrict this.

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My Answer:
One possible solution is to use session management to track the access code usage. When a user enters an access code, you can store the access code and the session ID in a database table. Then, whenever a user tries to access the webpage with the same access code from a different device or browser tab, you can check if the access code is already being used in another session. If it is, you can deny access to the webpage.

You can also consider using cookies to track the access code usage. When a user enters an access code, you can set a cookie with the access code and a unique identifier for the device or browser tab. Then, whenever a user tries to access the webpage with the same access code from a different device or browser tab, you can check if the cookie is already set. If it is, you can deny access to the webpage.

Overall, using session management or cookies to track access code usage can provide a more reliable way to restrict multiple access to a webpage at the same time.