Use system keyring service for password auth

LICENSE

@@ -1,4 +1,8 @@
+<<<<<<< HEAD
 Copyright 2019-2020 Garmelon, I-Al-Istannen, danstooamerican, pavelzw, TheChristophe
+=======
+Copyright 2019-2020 Garmelon, I-Al-Istannen, danstooamerican, pavelzw, Scriptim
+>>>>>>> f89226c (Use system keyring service for password auth)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in

PFERD/authenticators.py

@@ -3,8 +3,19 @@ General authenticators useful in many situations
 """
 
 import getpass
+import logging
 from typing import Optional, Tuple
 
+from .logging import PrettyLogger
+
+LOGGER = logging.getLogger(__name__)
+PRETTY = PrettyLogger(LOGGER)
+
+try:
+    import keyring
+except ImportError:
+    PRETTY.warning("Keyring module not found, KeyringAuthenticator won't work!")
+
 
 class TfaAuthenticator:
     # pylint: disable=too-few-public-methods
@@ -123,3 +134,81 @@ class UserPassAuthenticator:
         if self._given_username is not None and self._given_password is not None:
             self._given_username = None
             self._given_password = None
+
+
+class KeyringAuthenticator(UserPassAuthenticator):
+    """
+    An authenticator for username-password combinations that stores the
+    password using the system keyring service and prompts the user for missing
+    information.
+    """
+
+    def get_credentials(self) -> Tuple[str, str]:
+        """
+        Returns a tuple (username, password). Prompts user for username or
+        password when necessary.
+        """
+
+        if self._username is None and self._given_username is not None:
+            self._username = self._given_username
+
+        if self._password is None and self._given_password is not None:
+            self._password = self._given_password
+
+        if self._username is not None and self._password is None:
+            self._load_password()
+
+        if self._username is None or self._password is None:
+            print(f"Enter credentials ({self._reason})")
+
+        username: str
+        if self._username is None:
+            username = input("Username: ")
+            self._username = username
+        else:
+            username = self._username
+
+        if self._password is None:
+            self._load_password()
+
+        password: str
+        if self._password is None:
+            password = getpass.getpass(prompt="Password: ")
+            self._password = password
+            self._save_password()
+        else:
+            password = self._password
+
+        return (username, password)
+
+    def _load_password(self) -> None:
+        """
+        Loads the saved password associated with self._username from the system
+        keyring service (or None if not password has been saved yet) and stores
+        it in self._password.
+        """
+        self._password = keyring.get_password("pferd-ilias", self._username)
+
+    def _save_password(self) -> None:
+        """
+        Saves self._password to the system keyring service and associates it
+        with self._username.
+        """
+        keyring.set_password("pferd-ilias", self._username, self._password)
+
+    def invalidate_credentials(self) -> None:
+        """
+        Marks the credentials as invalid. If only a username was supplied in
+        the constructor, assumes that the username is valid and only the
+        password is invalid. If only a password was supplied in the
+        constructor, assumes that the password is valid and only the username
+        is invalid. Otherwise, assumes that username and password are both
+        invalid.
+        """
+
+        try:
+            keyring.delete_password("pferd-ilias", self._username)
+        except keyring.errors.PasswordDeleteError:
+            pass
+
+        super().invalidate_credentials()

PFERD/ilias/__init__.py

@@ -2,7 +2,8 @@
 Synchronizing files from ILIAS instances (https://www.ilias.de/).
 """
 
-from .authenticators import IliasAuthenticator, KitShibbolethAuthenticator
+from .authenticators import (IliasAuthenticator, KitShibbolethAuthenticator,
+                             KeyringKitShibbolethAuthenticator)
 from .crawler import (IliasCrawler, IliasCrawlerEntry, IliasDirectoryFilter,
                       IliasElementType)
 from .downloader import (IliasDownloader, IliasDownloadInfo,

PFERD/ilias/authenticators.py

@@ -37,8 +37,12 @@ class KitShibbolethAuthenticator(IliasAuthenticator):
     Authenticate via KIT's shibboleth system.
     """
 
-    def __init__(self, username: Optional[str] = None, password: Optional[str] = None) -> None:
-        self._auth = UserPassAuthenticator("KIT ILIAS Shibboleth", username, password)
+    def __init__(self, authenticator: Optional[UserPassAuthenticator] = None) -> None:
+        if authenticator:
+            self._auth = authenticator
+        else:
+            self._auth = UserPassAuthenticator("KIT ILIAS Shibboleth")
+
         self._tfa_auth = TfaAuthenticator("KIT ILIAS Shibboleth")
 
     def authenticate(self, sess: requests.Session) -> None:

requirements.txt

@@ -1,3 +1,4 @@
 requests>=2.21.0
 beautifulsoup4>=4.7.1
 rich>=2.1.0
+keyring>=21.5.0

setup.py

@@ -7,7 +7,8 @@ setup(
     install_requires=[
         "requests>=2.21.0",
         "beautifulsoup4>=4.7.1",
-        "rich>=2.1.0"
+        "rich>=2.1.0",
+        "keyring>=21.5.0"
     ],
 )
 

sync_url.py

@@ -8,10 +8,11 @@ import argparse
 import logging
 import sys
 from pathlib import Path, PurePath
-from typing import Optional, Tuple
+from typing import Optional
 from urllib.parse import urlparse
 
 from PFERD import Pferd
+from PFERD.authenticators import KeyringAuthenticator, UserPassAuthenticator
 from PFERD.cookie_jar import CookieJar
 from PFERD.ilias import (IliasCrawler, IliasElementType,
                          KitShibbolethAuthenticator)
@@ -25,9 +26,9 @@ _LOGGER = logging.getLogger("sync_url")
 _PRETTY = PrettyLogger(_LOGGER)
 
 
-def _extract_credentials(file_path: Optional[str]) -> Tuple[Optional[str], Optional[str]]:
+def _extract_credentials(file_path: Optional[str]) -> UserPassAuthenticator:
     if not file_path:
-        return (None, None)
+        return UserPassAuthenticator("KIT ILIAS Shibboleth", None, None)
 
     if not Path(file_path).exists():
         _PRETTY.error("Credential file does not exist")
@@ -39,7 +40,7 @@ def _extract_credentials(file_path: Optional[str]) -> Tuple[Optional[str], Optio
 
         name = read_name if read_name else None
         password = read_password[0] if read_password else None
-        return (name, password)
+        return UserPassAuthenticator("KIT ILIAS Shibboleth", username=name, password=password)
 
 
 def _resolve_remote_first(_path: PurePath, _conflict: ConflictType) -> FileConflictResolution:
@@ -71,6 +72,8 @@ def main() -> None:
     parser.add_argument('--credential-file', nargs='?', default=None,
                         help="Path to a file containing credentials for Ilias. The file must have "
                         "one line in the following format: '<user>:<password>'")
+    parser.add_argument("-k", "--keyring", action="store_true",
+                        help="Use the system keyring service for authentication")
     parser.add_argument('--no-videos', nargs='?', default=None, help="Don't download videos")
     parser.add_argument('--local-first', action="store_true",
                         help="Don't prompt for confirmation, keep existing files")
@@ -85,10 +88,21 @@ def main() -> None:
     cookie_jar = CookieJar(to_path(args.cookies) if args.cookies else None)
     session = cookie_jar.create_session()
 
-    username, password = _extract_credentials(args.credential_file)
-    authenticator = KitShibbolethAuthenticator(username=username, password=password)
+    if args.keyring:
+        if not args.username:
+            _PRETTY.error("Keyring auth selected but no --username passed!")
+            return
+        inner_auth: UserPassAuthenticator = KeyringAuthenticator(
+            "KIT ILIAS Shibboleth", username=args.username, password=args.password
+        )
+    else:
+        inner_auth = _extract_credentials(args.credential_file)
+
+    username, password = inner_auth.get_credentials()
+    authenticator = KitShibbolethAuthenticator(inner_auth)
 
     url = urlparse(args.url)
+
     crawler = IliasCrawler(url.scheme + '://' + url.netloc, session,
                            authenticator, lambda x, y: True)
 
@@ -125,6 +139,7 @@ def main() -> None:
         file_confilict_resolver = resolve_prompt_user
 
     pferd.enable_logging()
+
     # fetch
     pferd.ilias_kit_folder(
         target=target,