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Crashes when trying to read from STDIN

See original GitHub issue

Problem Description

Always crashes when trying to read from STDIN.

Steps to reproduce the behavior:

  1. Create an empty file empty, i.e. touch empty.
  2. tail -f ./empty | mitmproxy --rfile - -n

What happens:

$ tail -f ./empty | mitmproxy --rfile - -n
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/mitmproxy/master.py", line 86, in run_loop
    loop()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/usr/local/lib/python3.7/dist-packages/urwid/compat.py", line 55, in reraise
    value = tp()
TypeError: 'NoneType' object is not callable

mitmproxy has crashed!
Please lodge a bug report at:
	https://github.com/mitmproxy/mitmproxy

$ tail -f ./empty | mitmproxy --rfile empty -n
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/mitmproxy/master.py", line 86, in run_loop
    loop()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/usr/local/lib/python3.7/dist-packages/urwid/compat.py", line 58, in reraise
    raise value
  File "/usr/lib/python3.7/asyncio/events.py", line 88, in _run
    self._context.run(self._callback, *self._args)
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 404, in <lambda>
    event_loop, callback, self.get_available_raw_input())
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 436, in get_available_raw_input
    codes = self._get_gpm_codes() + self._get_keyboard_codes()
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 510, in _get_keyboard_codes
    code = self._getch_nodelay()
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 644, in _getch_nodelay
    return self._getch(0)
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 554, in _getch
    return ord(os.read(self._term_input_file.fileno(), 1))
TypeError: ord() expected a character, but string of length 0 found

mitmproxy has crashed!
Please lodge a bug report at:
	https://github.com/mitmproxy/mitmproxy

Important: If you load the file directly, it always works!

Also, with a real-life file, the errors vary. It always takes a long time showing nothing and then crashes:

$ tail -f ./mitmproxy-flow.cap | mitmproxy --rfile - -n

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/mitmproxy/master.py", line 86, in run_loop
    loop()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/usr/local/lib/python3.7/dist-packages/urwid/compat.py", line 55, in reraise
    value = tp()
TypeError: 'NoneType' object is not callable

mitmproxy has crashed!
Please lodge a bug report at:
	https://github.com/mitmproxy/mitmproxy
sys:1: RuntimeWarning: coroutine 'Master._shutdown' was never awaited
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

$ tail -f ./mitmproxy-flow.cap | mitmproxy --rfile - -n
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/mitmproxy/master.py", line 86, in run_loop
    loop()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/usr/local/lib/python3.7/dist-packages/urwid/compat.py", line 55, in reraise
    value = tp()
TypeError: 'NoneType' object is not callable

mitmproxy has crashed!
Please lodge a bug report at:
	https://github.com/mitmproxy/mitmproxy
sys:1: RuntimeWarning: coroutine 'Master._shutdown' was never awaited
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

I’ve also tried to not write into the file simoultaneously, and avoid using the -f command with tail. Nothing prevents the crashes.

$ tail ./empty | mitmproxy --rfile - -n
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/mitmproxy/master.py", line 86, in run_loop
    loop()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/usr/local/lib/python3.7/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/usr/local/lib/python3.7/dist-packages/urwid/compat.py", line 58, in reraise
    raise value
  File "/usr/lib/python3.7/asyncio/events.py", line 88, in _run
    self._context.run(self._callback, *self._args)
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 404, in <lambda>
    event_loop, callback, self.get_available_raw_input())
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 436, in get_available_raw_input
    codes = self._get_gpm_codes() + self._get_keyboard_codes()
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 510, in _get_keyboard_codes
    code = self._getch_nodelay()
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 644, in _getch_nodelay
    return self._getch(0)
  File "/usr/local/lib/python3.7/dist-packages/urwid/raw_display.py", line 554, in _getch
    return ord(os.read(self._term_input_file.fileno(), 1))
TypeError: ord() expected a character, but string of length 0 found

mitmproxy has crashed!
Please lodge a bug report at:
	https://github.com/mitmproxy/mitmproxy

Important: When loading the file directly (not from STDIN), it works without any problem, even for an empty file!

Previous crashes/information: https://github.com/mitmproxy/mitmproxy/issues/1002#issuecomment-665169972

System Information

$ mitmproxy --version
Mitmproxy: 5.2
Python:    3.7.3
OpenSSL:   OpenSSL 1.1.1d  10 Sep 2019
Platform:  Linux-5.4.51-v7l+-armv7l-with-debian-10.4

Issue Analytics

  • State:closed
  • Created 3 years ago
  • Comments:9 (9 by maintainers)

github_iconTop GitHub Comments

1reaction
rugkcommented, Jul 29, 2020
0reactions
mhilscommented, Jul 29, 2020

pipx works just as well, it’s just a more user-friendly wrapper around virtualenvs. Please feel free to report this upstream, urwid shouldn’t crash if you provide a file as stdin. That being said, you don’t want to pipe into mitmproxy, that doesn’t work well because you need stdin for keyboard input.

As a general comment, you have posted a serious double-digit number of comments over the last two days on our issue tracker. We appreciate feedback, but can’t cope with that. Please tune down your volume considerably and try to be more helpful than demanding. Thanks.

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