bugfix: deprecated asyncio usage since python 3.9

[mattia-lecci]

See #583 . Reported here:

Specs

• System: Windows 10
• Python: 3.10.5
• pyshark: 0.5.3
• Environment: venv

Origins of the issue

The issues seems to be related to this update.

The asyncio module has received many new features, usability and performance improvements. Notable changes include:

[...]
The new asyncio.current_task() function returns the currently running Task instance, and the new asyncio.all_tasks() function returns a set of all existing Task instances in a given loop. The Task.current_task() and Task.all_tasks() methods have been deprecated. (Contributed by Andrew Svetlov in bpo-32250.)

From asyncio doc:

Deprecated since version 3.7, will be removed in version 3.9: Do not call this as a task method. Use the asyncio.all_tasks() function instead.

Working fix

Modified pyshark\capture\capture.py:176 in my local .venv from:

if asyncio.Task.all_tasks():

to

if asyncio.all_tasks():

[amitesh-c]

Have you verified the fix on windows with jupyter notebook ? It seems to throw below error. Any ideas ?

RuntimeError Traceback (most recent call last)
c:\my_projects\23_pyshark_snoop.ipynb Cell 1 in 8
4 # filename = 'data/CIS_TIMEOUT_with_uuids.pcapng'
5 # filename = 'data/test.cap'
7 cap = pyshark.FileCapture(filename)
----> 8 print(cap[0])

hand edited the fix to capture.py

File ~\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\pyshark\capture\file_capture.py:72, in FileCapture.getitem(self, packet_index)
70 while packet_index >= len(self._packets):
71 try:
---> 72 self.next()
73 except StopIteration:
74 # We read the whole file, and there's still not such packet.
75 raise KeyError("Packet of index %d does not exist in capture" % packet_index)

File ~\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\pyshark\capture\file_capture.py:62, in FileCapture.next(self)
60 return self._packet_generator.send(None)
61 elif self._current_packet >= len(self._packets):
...
578 if events._get_running_loop() is not None:
--> 579 raise RuntimeError(
580 'Cannot run the event loop while another loop is running')

[mattia-lecci]

i had the same problem when running it into a jupyter notebook.
In #542 they say that it is expected and pyshark is not supported by jupyter notebooks.
Running it from a normal python script works for me, have you tried that?

[amitesh-c]

Indeed the issue looks related to asyncio event loop by pyshark conflicts with jupyter notebook. It would be nice to have a solution to this. Normal script works fine. Thanks for the prompt response.

[KimiNewt]

Note that this drops compatibility with Python 3.5/6. Since we're way past the EoL for those I'm fine with it, but I'm gonna make the appropriate changes to denote that