Refactor multifilesystem

radicale/storage/multifilesystem/lock.py

@@ -0,0 +1,72 @@
+# This file is part of Radicale Server - Calendar Server
+# Copyright © 2014 Jean-Marc Martins
+# 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/>.
+
+import contextlib
+import logging
+import os
+import shlex
+import subprocess
+
+from radicale import pathutils
+from radicale.log import logger
+
+
+class CollectionLockMixin:
+    @classmethod
+    def static_init(cls):
+        super().static_init()
+        folder = os.path.expanduser(cls.configuration.get(
+            "storage", "filesystem_folder"))
+        lock_path = os.path.join(folder, ".Radicale.lock")
+        cls._lock = pathutils.RwLock(lock_path)
+
+    def _acquire_cache_lock(self, ns=""):
+        if self._lock.locked == "w":
+            return contextlib.ExitStack()
+        cache_folder = os.path.join(self._filesystem_path, ".Radicale.cache")
+        self._makedirs_synced(cache_folder)
+        lock_path = os.path.join(cache_folder,
+                                 ".Radicale.lock" + (".%s" % ns if ns else ""))
+        lock = pathutils.RwLock(lock_path)
+        return lock.acquire("w")
+
+    @classmethod
+    @contextlib.contextmanager
+    def acquire_lock(cls, mode, user=None):
+        with cls._lock.acquire(mode):
+            yield
+            # execute hook
+            hook = cls.configuration.get("storage", "hook")
+            if mode == "w" and hook:
+                folder = os.path.expanduser(cls.configuration.get(
+                    "storage", "filesystem_folder"))
+                logger.debug("Running hook")
+                debug = logger.isEnabledFor(logging.DEBUG)
+                p = subprocess.Popen(
+                    hook % {"user": shlex.quote(user or "Anonymous")},
+                    stdin=subprocess.DEVNULL,
+                    stdout=subprocess.PIPE if debug else subprocess.DEVNULL,
+                    stderr=subprocess.PIPE if debug else subprocess.DEVNULL,
+                    shell=True, universal_newlines=True, cwd=folder)
+                stdout_data, stderr_data = p.communicate()
+                if stdout_data:
+                    logger.debug("Captured stdout hook:\n%s", stdout_data)
+                if stderr_data:
+                    logger.debug("Captured stderr hook:\n%s", stderr_data)
+                if p.returncode != 0:
+                    raise subprocess.CalledProcessError(p.returncode, p.args)