Is it possible to request posting rights from facebook only when an action is performed?

Question

Facebook

Good evening.

Given:
A website (webapp) with a Facebook login button. After authorization, a button appears that leaves an arbitrary message on the visitor's wall.

Found solution:
In the application's access rights, add the ability to leave publications on the user's wall. After authorization, you can pull the graph api (post /me/feed) and leave whatever you want.
As you wish:
When authorizing, do not request explicitly redundant posting rights at any time. And when you press a key, say "Leave an ad on your FB wall", does the user see a popup with a confirmation of a one-time publication on his wall?
Can this be done?
Vkontakte does this automatically, if you pull the wall.post method from the JS SDK, the user will see a post confirmation window ... The question is whether Facebook can do this ...