I have a similar issue to this:
How can I skip Fabric connections that ask for a password?
which has no answer. I'm looking for a way to get Fabric to consider bad any host asking for a password instead of an SSH key login, since this means the user I'm connecting as doesn't have an account on the server (and I'm iterating through a large list of hosts). I've tried setting
env.password = None
env.password = 'none'
I believe env.abort_on_prompts will achieve what you need, i.e. fail if there is a need for any kind of user interaction, while working when public key authentication is possible.
According to the documentation, this option calls abort() which in turn make use of sys.exit, which raises SystemExit making it possible to detect and recover from inner calls to
abort by using
except SystemExit or similar.