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Python API and shell utilities to monitor file system events.
Example API Usage
A simple program that uses watchdog to monitor directories specified
as command-line arguments and logs events generated::
import sys
import time
from watchdog.observers import Observer
from import LoggingEventHandler
if __name__ == "__main__":
path = sys.argv[1]
event_handler = LoggingEventHandler()
observer = Observer()
observer.schedule(event_handler, path, recursive=True)
while True:
except KeyboardInterrupt:
Shell Utilities
Watchdog comes with a utility script called ``watchmedo``.
Please type ``watchmedo --help`` at the shell prompt to
know more about this tool.
Here is how you can log the current directory recursively
for events related only to ``*.py`` and ``*.txt`` files while
ignoring all directory events::
watchmedo log \
--patterns="*.py;*.txt" \
--ignore-directories \
--recursive \
You can use the ``shell-command`` subcommand to execute shell commands in
response to events::
watchmedo shell-command \
--patterns="*.py;*.txt" \
--recursive \
--command='echo "${watch_src_path}"' \
Please see the help information for these commands by typing::
watchmedo [command] --help
About ``watchmedo`` Tricks
``watchmedo`` can read ``tricks.yaml`` files and execute tricks within them in
response to file system events. Tricks are actually event handlers that
subclass ``watchdog.tricks.Trick`` and are written by plugin authors. Trick
classes are augmented with a few additional features that regular event handlers
don't need.
An example ``tricks.yaml`` file::
- watchdog.tricks.LoggerTrick:
patterns: ["*.py", "*.js"]
- watchmedo_webtricks.GoogleClosureTrick:
patterns: ['*.js']
hash_names: true
mappings_format: json # json|yaml|python
mappings_module: app/javascript_mappings
suffix: .min.js
compilation_level: advanced # simple|advanced
source_directory: app/static/js/
destination_directory: app/public/js/
- app/static/js/vendor/jquery*.js
- app/static/js/base.js
- app/static/js/index-page.js
- app/static/js/vendor/jquery*.js
- app/static/js/base.js
- app/static/js/about-page/**/*.js
The directory containing the ``tricks.yaml`` file will be monitored. Each trick
class is initialized with its corresponding keys in the ``tricks.yaml`` file as
arguments and events are fed to an instance of this class as they arrive.
Tricks will be included in the 0.5.0 release. I need community input about them.
Please file enhancement requests at the `issue tracker`_.
Installing from PyPI using ``pip``::
pip install watchdog
Installing from PyPI using ``easy_install``::
easy_install watchdog
Installing from source::
python install
Installation Caveats
The ``watchmedo`` script depends on PyYAML_ which links with LibYAML_.
On Mac OS X, you can use homebrew_ to install LibYAML::
brew install libyaml
On Linux, use your favorite package manager to install LibYAML. Here's how you
do it on Ubuntu::
sudo aptitude install libyaml-dev
On Windows, please install PyYAML_ using the binaries they provide.
You can browse the latest release documentation_ online.
Supported Platforms
* Linux 2.6 (inotify)
* Mac OS X (FSEvents, kqueue)
* FreeBSD/BSD (kqueue)
* Windows (ReadDirectoryChangesW with I/O completion ports;
ReadDirectoryChangesW worker threads)
* OS-independent (polling the disk for directory snapshots and comparing them
periodically; slow and not recommended)
1. Python 2.5 or above.
2. XCode_ (only on Mac OS X)
3. PyYAML_
4. argh_
5. select_backport_ (select.kqueue replacement for Python2.5/2.6 on BSD/Mac OS X)
6. pathtools_
7. Brownie_
Watchdog is licensed under the terms of the `MIT License`_.
Copyright (C) 2010 `Gora Khargosh`_ and the Watchdog authors.
Project `source code`_ is available at Github. Please report bugs and file
enhancement requests at the `issue tracker`_.
Why Watchdog?
Too many people tried to do the same thing and none did what I needed Python
to do:
* pnotify_
* `unison fsmonitor`_
* fsmonitor_
* guard_
* pyinotify_
* `inotify-tools`_
* jnotify_
* treewalker_
* `file.monitor`_
* pyfilesystem_
.. links:
.. _Gora Khargosh:
.. _source code:
.. _issue tracker:
.. _MIT License:
.. _documentation:
.. _homebrew:
.. _select_backport:
.. _argh:
.. _PyYAML:
.. _XCode:
.. _LibYAML:
.. _pathtools:
.. _Brownie:
.. _pnotify:
.. _unison fsmonitor:
.. _fsmonitor:
.. _guard:
.. _pyinotify:
.. _inotify-tools:
.. _jnotify:
.. _treewalker:
.. _file.monitor:
.. _pyfilesystem:
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