TCP port monitoring and discovery
.. image:: https://img.shields.io/pypi/v/portend.svg :target: https://pypi.org/project/portend
.. image:: https://img.shields.io/pypi/pyversions/portend.svg
.. image:: https://github.com/jaraco/portend/workflows/tests/badge.svg :target: https://github.com/jaraco/portend/actions?query=workflow%3A%22tests%22 :alt: tests
.. image:: https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/charliermarsh/ruff/main/assets/badge/v2.json :target: https://github.com/astral-sh/ruff :alt: Ruff
.. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/psf/black :alt: Code style: Black
.. image:: https://readthedocs.org/projects/portend/badge/?version=latest :target: https://portend.readthedocs.io/en/latest/?badge=latest
.. image:: https://img.shields.io/badge/skeleton-2023-informational :target: https://blog.jaraco.com/skeleton
por·tend pôrˈtend/ verb
be a sign or warning that (something, especially something momentous or calamitous) is likely to happen.
Use portend to monitor TCP ports for bound or unbound states.
For example, to wait for a port to be occupied, timing out after 3 seconds::
portend.occupied('www.google.com', 80, timeout=3)
Or to wait for a port to be free, timing out after 5 seconds::
portend.free('::1', 80, timeout=5)
The portend may also be executed directly. If the function succeeds, it returns nothing and exits with a status of 0. If it fails, it prints a message and exits with a status of 1. For example::
python -m portend localhost:31923 free
(exits immediately)
python -m portend -t 1 localhost:31923 occupied
(one second passes)
Port 31923 not bound on localhost.
Portend also exposes a find_available_local_port
for identifying
a suitable port for binding locally::
port = portend.find_available_local_port()
print(port, "is available for binding")
Portend additionally exposes the lower-level port checking functionality
in the Checker
class, which currently exposes only one public
method, assert_free
::
portend.Checker().assert_free('localhost', 31923)
If assert_free is passed a host/port combination that is occupied by
a bound listener (i.e. a TCP connection is established to that host/port),
assert_free will raise a PortNotFree
exception.