AuthenticationDriver.py

# TODO: Exceptions Different Error Classes?
# - Card not present / token_id not found
# - Transport Error (try again)
# - Key Error (retry is futile?)
# - Unknown Token Error

class AuthenticationDriver(object):
	def __init__(self, slot=4):
		self.slot = slot
	
	def detect(self):
		"""Scans for Authentication Tokens, returns Token ID on success"""
		return
		
	def check(self, token_id, transport_key, known_secret):
		"""Connect and read the token, verify against known secret
		Returns True when auth token seems valid"""
		return False
		
	def withdraw(self, token_id, transport_key):
		"""Invalidate a token (by overwriting secret with garbage)"""
		return False
		
	def assign(self, token_id, transport_key)
		"""Initialize a new token with given parameters"""
		return False