modified 1.01

Python file modification tracker

Summary

modified tracks the files of the currently running application and facilitates restart if any files have changed. By default it will track all Python files, including all modules loaded by the app. If there are additional files you need to track such as config files, templates, etc., you can add those using a glob pattern.

The simplest usage is to simply run the hup_hook. By default, this will build a dict of all currently loaded code files with their timestamps and register a handler for signal.SIGHUP. When the application receives signal.SIGHUP, the hook will check to see if any of the files have been modified, and issue signal.SIGTERM, if so.

IMPORTANT: If a file ends in .pyc, modified will attempt to retrieve the timestamp from the .py file instead.

>>> import modified
>>> modified.hup_hook()

Installation

$> pip install modified

Functions

files()

Scan all modules in the currently running app to create a dict of all files and their modified time.

The scan only occurs the first time this function is called. Subsequent calls simply return the global dict.

>>> import modified
>>> modified.files()
{'.../env32/lib/python3.2/copyreg.py': 1368477498.0,
 '.../env32/lib/python3.2/_weakrefset.py': 1368477497.0,
 '.../env32/lib/python3.2/os.py': 1368477498.0,
 'modified.py': 1384228495.0,
 '.../env32/lib/python3.2/genericpath.py': 1368477498.0,
 '.../env32/lib/python3.2/abc.py': 1368477497.0,
 '.../env32/lib/python3.2/posixpath.py': 1368477498.0,
 '.../env32/lib/python3.2/stat.py': 1368477498.0,
 '.../env32/lib/python3.2/_abcoll.py': 1368477497.0}

module_files(module, dependencies_dict=None)

Scan a module and its entire dependency tree to create a dict of all files and their modified time.

Pass an existing dict to add only unscanned files or None to create a new file dict

>>> import modified
>>> import sh
>>> modified.module_files(sh)
{'.../env32/lib/python3.2/site-packages/sh-1.09-py3.2.egg/sh.py': 1384230023.0}

modified()

Return the list of files modified since the initial scan.

>>> import modified
>>> modified.files()
{'.../env32/lib/python3.2/copyreg.py': 1368477498.0,
 '.../env32/lib/python3.2/_weakrefset.py': 1368477497.0,
 '.../env32/lib/python3.2/os.py': 1368477498.0,
 'modified.py': 1384228495.0,
 '.../env32/lib/python3.2/genericpath.py': 1368477498.0,
 '.../env32/lib/python3.2/abc.py': 1368477497.0,
 '.../env32/lib/python3.2/posixpath.py': 1368477498.0,
 '.../env32/lib/python3.2/stat.py': 1368477498.0,
 '.../env32/lib/python3.2/_abcoll.py': 1368477497.0}
>>> open('modified.py', 'a+').close()
>>> modified.modified()
['modified.py']

track(*args)

Track additional files. It is often useful to use glob.glob here. For instance:

>>> import modified
>>> import glob
>>> modified.track('config.ini', glob.glob('templates/*.pt'), glob.glob('db/*.db'))

hup_hook(signal_or_callable=signal.SIGTERM, verbose=False)

Register a signal handler for signal.SIGHUP that checks for modified files and only acts if at least one modified file is found.

You can pass either a signal or a callable for signal_or_callable. The signal can be specified by name or number. If specifying by name, the ‘SIG’ portion is optional. For example, valid values for SIGINT include ‘INT’, ‘SIGINT’ and signal.SIGINT.

Alternatively, you can pass a callable that will be called with the list of changed files. So the call signature should be func(list). The return value of the callable is ignored.

The verbose parameter can be True, False or a callable. True indicates that a message should be printed. A callable will be called with the message to print.

>>> import modified
>>> import logging
>>> modified.hup_hook('INT', logging.info)
...
Sending SIGINT because modified.py and 3 other files changed.

With a callable:

>>> import modified
>>> import logging
>>> shutting_down = False
>>> def set_shutdown():
...     global shutting_down
...     shutting_down = True
>>> modified.hup_hook(set_shutdown)
...
Calling set_shutdown because modified.py and 3 other files changed.