FB.event.subscribe comment.create acting without action from user [duplicate]

Question

This question already has an answer here:

• Calling a PHP Method from JavaScript [closed] 2 answers

OK, so here is my problem. I'm trying to get an email sent to the author of individual posts once a comments is made in facebook comments (to notify the author that comments have been made). The comment box is in a K2 item (in Joomla).

FB.event.subscribe comment.create is working, I've tried it with just alert('fired'); and that works fine. But when I enter the PHP it just starts sending emails to the first email given everytime someone enters the page. How do I get it to send email only when a comment is created or added?

<script>
    window.fbAsyncInit = function(){ 
        FB.Event.subscribe('comment.create', function(response){
            <?php
                if ($this->item->author->name = 'Author1'){
                    $to = "author1@mydomain.com";
                }else if ($this->item->author->name = 'author2'){
                    $to = "author2@mydomain.com";
                };
                $subject = "Test mail";
                $message = "Hello! This is a simple email message. live run";
                $from = "admin@mydomain.com";
                $headers = "From:" . $from;
                mail($to,$subject,$message,$headers);
            ?>;
        });
    };
</script>

EDIT Please follow this link PHP variable from external file? for a complete solution on this subject and what I was trying to accomplish here.

Answer 1

PHP is executed server-side. By the time the callback is fired, the PHP has already executed (when the page was requested).

Instead, you need to make an AJAX call inside of your callback to a PHP script that will do whatever it is that you need it to do:

window.fbAsyncInit = function(){ 
    FB.Event.subscribe('comment.create', function(response){
        $.post('/sendemail.php');
    });
};

Put the rest of your code in sendemail.php

This assumes you are using jQuery.

Note: This is a pretty bad idea considering that, without any validation, a user can just send repeated requests to sendemail.php and spam the heck out of someone's mailbox. Consider security, rate limiting, etc.