Nrthugu

Ok, so now I'm building a VueJS + Laravel web application. My main function for the app is when it reaches a certain time(startTime), the user will be able to click a button and store the time difference between the time when user pressed the button and the startTime to the database. Note: there will be around 25users submitting at the same time, spamming the record button. Each user can only record once. The one with the shortest difference in time will win the competition.

Currently, I've thought of two ways,

(i) Use javascript Date.now() to get the current time and subtract by the start time and then send the timeDiff from front end to backend. It's fast but Date.now() depends on the client system time, which if the user changes its' system time, they can either draw earlier or later since it doesn't matter as long as the time matches the start time.

(ii) Everything is processed in the backend. A timestamp will be generated on the server every time a user press the record button. It doesn't have the issue (i) has but due to the performance of Laravel, it looks like the server is stalling the request thus making the timestamp not accurate at all.

Any suggestions or advices? I'm still new to all this and these are the 2 methods I can think of right now.

if(auth()->user()->recorded !== 1){ //check if recorded



        //create timestamp in epoch

        $pressTime = microtime(true)*1000; 

        $offTimeStart = $user->startTime;

        $offTimeEnd = $user->endTime;

        $pressedTime = $user->pressTime;//initially 999999999



       //prevent user spamming record btn

       if($pressTime > $pressedTime){ return something;}



        //check if still within the range

        if($pressTime >= $offTimeStart && $pressTime < $offTimeEnd){

            if($user != null){

                $user->update([

                    'pressTime' => $pressTime,

                    'recorded' => 1 

                ]);}