Python API and shell utilities to monitor file system events.
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 watchdog.events import LoggingEventHandler
if __name__ == "__main__":
path = sys.argv[1]
event_handler = LoggingEventHandler()
observer = Observer()
observer.schedule(event_handler, path, recursive=True)
observer.start()
try:
while True:
time.sleep(1)
except KeyboardInterrupt:
observer.stop()
observer.join()
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
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:
tricks:
- 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/
files:
index-page:
- app/static/js/vendor/jquery*.js
- app/static/js/base.js
- app/static/js/index-page.js
about-page:
- 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 setup.py install
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.
- 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)
- Python 2.5 or above.
- XCode (only on Mac OS X)
- PyYAML
- argh
- select_backport (select.kqueue replacement for Python2.5/2.6 on BSD/Mac OS X)
- pathtools
- 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.
Too many people tried to do the same thing and none did what I needed Python to do: