While I'm not sure if there is any RSS reader that can actually support restricted feeds, you could actually make it work with Feedly something like the following.
In your app.yaml
you should not require login or anything for the rss URL so it will look something like this:
- url: /rss/.*
script: main.rss
And then you should simply generate some unique keys (uuid
for example) and only if that is on some list responding with the actual feed, otherwise return the access denied.
Your URL will look something like this:
http://www.my-company.com/rss/550e8400-e29b-41d4-a716-446655440000
Which is public and not easily guessable. On regular basis you could even reset that key, or have it auto generated per user, which is a better option in my opinion.