Restructure crawling and auth related modules

PFERD/auth/tfa.py

@@ -0,0 +1,36 @@
+from typing import Tuple
+
+from ..config import Config
+from ..logging import log
+from ..utils import ainput
+from .authenticator import Authenticator, AuthException, AuthSection
+
+
+class TfaAuthenticator(Authenticator):
+    def __init__(
+            self,
+            name: str,
+            section: AuthSection,
+            config: Config,
+    ) -> None:
+        super().__init__(name, section, config)
+
+    async def username(self) -> str:
+        raise AuthException("TFA authenticator does not support usernames")
+
+    async def password(self) -> str:
+        async with log.exclusive_output():
+            code = await ainput("TFA code: ")
+            return code
+
+    async def credentials(self) -> Tuple[str, str]:
+        raise AuthException("TFA authenticator does not support usernames")
+
+    def invalidate_username(self) -> None:
+        raise AuthException("TFA authenticator does not support usernames")
+
+    def invalidate_password(self) -> None:
+        pass
+
+    def invalidate_credentials(self) -> None:
+        pass