什么是最好的PHP函数来隐藏在后端的文件？

Question

I have files in different formats: ePub/mobi/pdf/etc.

But I don't want anyone to access those files and certain files cannot be access by some users. So I cannot use HTTP to protect the folder that contains the files because it might give access to one user to all the files...

So is there a PHP function that can get a file from a folder that cannot be access publicly to then send it back to the user?

Thanks in advance!

Answer 1

Just store the file out of the root directory that holds all of your front-facing files. So assuming your directory structure is as such:

root
-- public_html
-- -- access_book.php
-- -- index.php
-- -- ...
-- books
-- -- mobi_dick.pdf
-- -- ...

Then, just grab your file with a relative path (here is an example pulled from readfile):

<?php
    // Replace this with the path to the actual file
    $file = '../books/mobi_dick.pdf';

    if (file_exists($file)) {
        header('Content-Description: File Transfer');
        header('Content-Type: application/octet-stream');
        header('Content-Disposition: attachment; filename='.basename($file));
        header('Content-Transfer-Encoding: binary');
        header('Expires: 0');
        header('Cache-Control: must-revalidate');
        header('Pragma: public');
        header('Content-Length: ' . filesize($file));

        ob_clean();
        flush();
        readfile($file);
        exit;
    }
?>

You may have to configure open_basedir for PHP to open a file outside of the web root.