platypush/platypush/backend/inotify.py
2020-09-09 02:16:13 +02:00

99 lines
4.2 KiB
Python

import os
from platypush.backend import Backend
from platypush.message.event.inotify import InotifyCreateEvent, InotifyDeleteEvent, \
InotifyOpenEvent, InotifyModifyEvent, InotifyCloseEvent, InotifyAccessEvent, InotifyMovedEvent
class InotifyBackend(Backend):
"""
(Linux only) This backend will listen for events on the filesystem (whether
a file/directory on a watch list is opened, modified, created, deleted,
closed or had its permissions changed) and will trigger a relevant event.
Triggers:
* :class:`platypush.message.event.inotify.InotifyCreateEvent` if a resource is created
* :class:`platypush.message.event.inotify.InotifyAccessEvent` if a resource is accessed
* :class:`platypush.message.event.inotify.InotifyOpenEvent` if a resource is opened
* :class:`platypush.message.event.inotify.InotifyModifyEvent` if a resource is modified
* :class:`platypush.message.event.inotify.InotifyPermissionsChangeEvent` if the permissions of a resource are changed
* :class:`platypush.message.event.inotify.InotifyCloseEvent` if a resource is closed
* :class:`platypush.message.event.inotify.InotifyDeleteEvent` if a resource is removed
Requires:
* **inotify** (``pip install inotify``)
"""
inotify_watch = None
def __init__(self, watch_paths=None, **kwargs):
"""
:param watch_paths: Filesystem resources to watch for events
:type watch_paths: str
"""
super().__init__(**kwargs)
self.watch_paths = set(map(
lambda path: os.path.abspath(os.path.expanduser(path)),
watch_paths if watch_paths else []))
def _cleanup(self):
if not self.inotify_watch:
return
for path in self.watch_paths:
self.inotify_watch.remove_watch(path)
self.inotify_watch = None
def run(self):
import inotify.adapters
super().run()
self.inotify_watch = inotify.adapters.Inotify()
for path in self.watch_paths:
self.inotify_watch.add_watch(path)
moved_file = None
self.logger.info('Initialized inotify file monitoring backend, monitored resources: {}'
.format(self.watch_paths))
try:
for inotify_event in self.inotify_watch.event_gen():
if inotify_event is not None:
(header, inotify_types, watch_path, filename) = inotify_event
event = None
resource_type = inotify_types[1] if len(inotify_types) > 1 else None
if moved_file:
new = filename if 'IN_MOVED_TO' in inotify_types else None
event = InotifyMovedEvent(path=watch_path, old=moved_file, new=new)
moved_file = None
if 'IN_OPEN' in inotify_types:
event = InotifyOpenEvent(path=watch_path, resource=filename, resource_type=resource_type)
elif 'IN_ACCESS' in inotify_types:
event = InotifyAccessEvent(path=watch_path, resource=filename, resource_type=resource_type)
elif 'IN_CREATE' in inotify_types:
event = InotifyCreateEvent(path=watch_path, resource=filename, resource_type=resource_type)
elif 'IN_MOVED_FROM' in inotify_types:
moved_file = filename
elif 'IN_MOVED_TO' in inotify_types and not moved_file:
event = InotifyMovedEvent(path=watch_path, old=None, new=filename)
elif 'IN_DELETE' in inotify_types:
event = InotifyDeleteEvent(path=watch_path, resource=filename, resource_type=resource_type)
elif 'IN_MODIFY' in inotify_types:
event = InotifyModifyEvent(path=watch_path, resource=filename, resource_type=resource_type)
elif 'IN_CLOSE_WRITE' in inotify_types or 'IN_CLOSE_NOWRITE' in inotify_types:
event = InotifyCloseEvent(path=watch_path, resource=filename, resource_type=resource_type)
if event:
self.bus.post(event)
finally:
self._cleanup()
# vim:sw=4:ts=4:et: