Download file one time only for auth user (Suggestion needed) I have a website has a books &amp; categorize each book to unites, each units has a download link.. 

when user have a role, he can download file just 1 time .. no more for each unit ..

for example:

Book1 --> unit1 --> download --> if(user NOT download) else { Remove Link }

Book1 --> unit2 --> download --> this link was removed since you download a file

Book1 --> unit3 --> download --> if(user NOT download) else { Remove Link }

Book2 --> unit1 --> download --> if(user NOT download) else { Remove Link }

Book2 --> unit2 --> download --> if(user NOT download) else { Remove Link }

Note: books &amp; unit is term, units are child in books. 

my idea for solve this issue is create a normal text field and set user id if he click on download link..

Any suggestion for solve a problem, way, or module, field setting ...
thanks every body
Please use the modules tag if you're looking for a module hosted at Drupal.org.

There exist a module named Deep Link.  With 13 installs and no full release in sight, I wouldn't have high hopes for the usefulness of this, but the project page says:


  Deep link module allows the direct access to a specific item of content under certain circumstances and limitations. Such as one-off or time-limited deeplinks.


There is also Expiring Private File Link.

It says:


  This module was created when the need arose to offer a downloadable file to users of a site, without revealing the actual URL of the file itself. It also allows through the permissions system a method of allowing the file to only be available for download to registered users. If enabled, anonymous users will see the same dynamic link as registered users, but when they click on it they are presented with a login dialog informing them they must register to have access to the file.


This is a sandbox for Drupal 7, so its usefulness is even more questionable, but you may still want to check it out.