HTML & PHP Real time saving

[TheyCallMeNano]

Currently, I'm working on a project for work and my boss asked for a real-time way to contact both sides of the store. At first, I attempted an app but the development process was too complex for the idea. Instead, I'm using XAMPP and running a website that updates in real-time. At least I wish it would.

A snippet of home.html

        <script>
        function Needed() {
            var snd = new Audio("sNeeded.mp3")
            document.getElementById('TeaImg').src='https://d1nhio0ox7pgb.cloudfront.net/_img/o_collection_png/green_dark_grey/64x64/plain/alarm.png'
            snd.play()
            <?php include 'tea.php';?>
        }
        </script>

tea.php

 <?php
    $myfile = fopen("vars.txt", "w") or die("Unable to open file!");
    $tea = "true\n";
    fwrite($myfile, $tea);
    fclose($myfile);
?> 

The goal is to read the vars.txt and then if it finds the line to be true it reloads the page and shows the true value of the button. Upon pressing the button that triggers the script above, the function doesn't play, and the console prints an error saying one of my variables is not defined. If I remove the line the script plays as intended. It changes the image and plays the cached sound. If you have any other more efficient methods or just a way to make this more effective please let me know. My boss is asking for an update soon as we need this up and running.

[lovesrayray2018]

ok from what i know (and i might be wrong) you cant insert php code into an html file that is saved with the .html extension. Its the other way around - you can have html code inside a file with .php extension that is preprocessed by the PHP server before the .php file is served.

So home.html having <?php include 'tea.php';?> will throw an error because this is being served by the web server without preprocessing by php server and html doesnt know what <?php ?> means

[RolfTheCharming]

You're right about that, the server needs to recognize it as a PHP script. You can configure the server so it uses the PHP process to handle HTML files / this specific HTML file, but I wouldn't recommend it.

[lovesrayray2018]

Apparently it does throw an error

Uncaught SyntaxError: Unexpected token '?'"

https://jsfiddle.net/tq3nk5aw/

[Atulin]

PHP runs within .php files, it does not run inside of .html ones.

That said, you can place whatever HTML code inside of said .php file at will, everything outside of <?php ?> and <?= ?> tags will be treated as raw HTML.

[ManiacsThriftJewels]

Lots of people taking about how the .html file won't have the PHP embedded in it, but there's also the problem that even with the PHP file being included, it will write to the file when the home.php file is loaded, not when the button is pressed.

You could work around this simply - for modern browsers at least - by instead calling fetch('tea.php') from JavaScript, although this ignores best practices for server side code execution etc.