ddmee / polling2

Powerful polling utility in Python

polling2

Never write another polling function again!

Documentation available at Read the Docs

You can install the package from Pypi

Polling2 is a powerful python utility used to wait for a function to return a certain expected condition.

Some possible uses cases include:

• Wait for API response to return with code 200
• Wait for a file to exist (or not exist)
• Wait for a thread lock on a resource to expire

Polling2 is handy for getting rid of all that duplicated polling-code. Often, applications require retrying until the correct response is returned. Why re-implement the ability to poll again and again? Use Polling2!

Polling2 is a fork of the original polling. It was forked when the original maintainer failed to respond to issues or PRs.

Polling2 is under active development. Would you like to see a particular feature? Ask and thou shall recieve.

Installation

pip install polling2

Development installation

# install lib, but use system links from the repo into sitepackages.
python setup.py develop
# install test dependenices.
python setup.py test
# run the tests
pytest tests

Note, tox is also available, as well as pre-commit.

# install tox and run it
pip install tox
tox

Pre-commit performs auto-formatting and things of that nature before each commit.

pip install pre-commit
pre-commit install

Now pre-commit will run automatically on git commit.

Example:

# This call will wait until the file exists, checking every 0.1 seconds and stopping after 3 seconds have elapsed
file_handle = polling2.poll(
    lambda: open('/tmp/myfile.txt'),
    ignore_exceptions=(IOError,),
    timeout=3,
    step=0.1)

# Polling will return the value of your polling function, so you can now interact with it
file_handle.close()

There are more examples in the documentation.

API and user guide at Read the Docs