PHP - Register User Before Downloading File

[johnny_v]

I would like to do the following:

• Provide PDF documents to visitors
• Require visitors to provide email address
• Prevent visitors from directly access download link. If they did not provide their email address, redirect them to do so.

I am not sure how to do this. Should I place the PDF's outside of the webroot directory? I am using Lighttpd on Debian.

Almost all the websites I see have this functionality implemented.

Thank you for any help.

[NogDog]

You can place the PDF outside of the web root directory tree, then have them submit their email via a form input. The form-handler it calls would then process the email address as desired and then serve up the PDF, e.g.:

<?php
if(!empty($_POST['email'])) {
   // save email in DB or whatever you want to do with it
   header("Content-Type:  application/pdf");
   readfile("../path/to/pdf/file.pdf");
   exit; // make sure no extraneous bytes get sent
}
else {
   // whatever you want to do if email not supplied
}

[johnny_v]

NogDog,

First off, thank you very much for your informative response.

When learning something, it is hard to articulate what exactly you are looking for and what you need help with.

Thank you for your script and not the normal response of "google it or it has already been answered"

Here is what I have:

<?php

$errors = array();
if(isset($_POST['email']) && !empty($_POST['email'])) 
{ 
   $_REQUEST['email'] = trim($_REQUEST['email']);
   
   if(substr_count($_POST['email'],"@") != 1 || stristr($_POST['email']," "))
   {
   		$errors[] = "Email address is invalid";
   		foreach($errors as $value){print "$value<br>";}
   		exit;
   }
   
   // save email in DB or whatever you want to do with it 
   header("Content-Type:  application/pdf");
   header('Content-Disposition: attachment; filename="downloaded.pdf"');
   readfile("../files/test.pdf"); 
   exit; // make sure no extraneous bytes get sent 
} 
else { 
   // whatever you want to do if email not supplied 
   exit;
}
?>

I can download the file via the form. However, I can also go via the URL and download the file.

How can I prevent direct access to the PDF, or am I doing something wrong?

Thank you.