How to secure file access using Carrierwave + S3 hosted on Heroku

Rails
1

My site is hosted on Heroku and I am using Carrierwave to upload files
to Amazon.

How can i restrict file access based on roles? Is this possible?
Using Devise and CanCan.

2

Yes, it is possible. You need to look into query string request
authentication in the amazon s3 docs. It has been pretty much created
for
this use case.