'Private' uploaded files (PDFs, images, etc.) will normally be only included in private posts and pages. But the files themselves can still be accessed by anyone if they know the corresponding URLs.
For example, a PDF file's URL might be
http://example.com/wp-content/uploads/minutes-20160924.pdf
and anyone could download that file because WordPress does not get a chance to check their authorisation.
The solution that the Private Uploads plugin uses involves moving any private files to a separate folder, and then configuring the web server to ask WordPress to authenticate access to files in that folder.
So the file's URL might now be
http://example.com/wp-content/uploads/private/minutes-20160924.pdf
and an HTTP server rewrite rule will convert this to
http://example.com/?pucd-folder=private&pucd-file=minutes-20160924.pdf
The Private Uploads plugin will intercept that URL and reject it with a 403 status code.
This plugin is more efficient than some similar ones because it only has to run when serving files in the private folder(s): the web server handles other uploaded files (ones not in the private folders) directly.
Install the plugin in the usual way and activate it.
Move your private uploads (PDFs, images, or whatever) into a separate sub-folder within the WordPress uploads folder (usually /wp-content/uploads). One way of creating such a folder and moving the private files is by means of the
Media Organiser plugin.
Then configure your web server as follows:
Nginx
Include a line like this in the server section of the Nginx configuration:
rewrite ^/wp-content/uploads/(private)/(.*)$ /?pucd-folder=$1&pucd-file=$2 break;
The folder name 'private' can be anything you like -- it just has to match the name of the folder where your private files are kept, and be enclosed in parentheses in the rewrite statement.
More than one private folder can be configured by adding more lines of the same form, for example:
rewrite ^/wp-content/uploads/(2017/secure)/(.*)$ /?pucd-folder=$1&pucd-file=$2 break;
Apache
Enchiridion has supplied the following configuration for Apache. Thank you.
Here's an equivalent rule for Apache to add to your existing rules:
RewriteRule ^wp-content/uploads/(private)/(.*)$ /?pucd-folder=$1&pucd-file=$2 [L]
Or you can copy/paste this entire block into your
.htaccess file. Add before the
# BEGIN WordPress block:
RewriteEngine On
RewriteBase /
Block unauthenticated user access to the /private/ uploads folder
RewriteRule ^wp-content/uploads/(private)/(.*)$ /?pucd-folder=$1&pucd-file=$2 [L]
Other web servers
are left as an exercise for the reader.
0.1.1
Tested with WordPress 5. Documentation tidied up.
0.1.0