refactor

radicale/rights/__init__.py

@@ -0,0 +1,84 @@
+# This file is part of Radicale Server - Calendar Server
+# Copyright © 2012-2017 Guillaume Ayoub
+# Copyright © 2017-2018 Unrud <unrud@outlook.com>
+#
+# This library is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Radicale.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Rights backends.
+
+This module loads the rights backend, according to the rights
+configuration.
+
+Default rights are based on a regex-based file whose name is specified in the
+config (section "right", key "file").
+
+Authentication login is matched against the "user" key, and collection's path
+is matched against the "collection" key. You can use Python's ConfigParser
+interpolation values %(login)s and %(path)s. You can also get groups from the
+user regex in the collection with {0}, {1}, etc.
+
+For example, for the "user" key, ".+" means "authenticated user" and ".*"
+means "anybody" (including anonymous users).
+
+Section names are only used for naming the rule.
+
+Leading or ending slashes are trimmed from collection's path.
+
+"""
+
+from importlib import import_module
+
+from radicale.log import logger
+
+INTERNAL_TYPES = ("authenticated", "owner_write", "owner_only", "from_file")
+
+
+def load(configuration):
+    """Load the rights manager chosen in configuration."""
+    rights_type = configuration.get("rights", "type")
+    if rights_type in INTERNAL_TYPES:
+        module = "radicale.rights.%s" % rights_type
+    else:
+        module = rights_type
+    try:
+        class_ = import_module(module).Rights
+    except Exception as e:
+        raise RuntimeError("Failed to load rights module %r: %s" %
+                           (rights_type, e)) from e
+    logger.info("Rights type is %r", rights_type)
+    return class_(configuration)
+
+
+def intersect_permissions(a, b="RrWw"):
+    return "".join(set(a).intersection(set(b)))
+
+
+class BaseRights:
+    def __init__(self, configuration):
+        self.configuration = configuration
+
+    def authorized(self, user, path, permissions):
+        """Check if the user is allowed to read or write the collection.
+
+        If ``user`` is empty, check for anonymous rights.
+
+        ``path`` is sanitized.
+
+        ``permissions`` can include "R", "r", "W", "w"
+
+        Returns granted rights.
+
+        """
+        raise NotImplementedError