Support python3; refactor asynchat to use aiofile.

[yetab]

Hi there!

Awesome work! I found python3 not working, so I did some patch work here.

I have updated the library to use python3 and refactored to use aiofile to resolve some compatibility issues.
I ran the unittests and they all passed.

If there is any issue, please let me know. Thanks.

[johnjohndoe]

It would be great if pidcat would also be fixed for Python3.

[marshall]

@yetab thanks so much for the PR!

I haven't thought about this codebase in quite some time.. and was pleasantly surprised people are still interested in contributing :)

the code looks sane, and I'd be happy to merge, but I tried running the tests locally in a python3 venv, and saw these two errors. any chance you can take a look?

❯ ADB=/Users/marshall/Library/Android/sdk/platform-tools/adb ./test.py
............/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/subprocess.py:1137: ResourceWarning: subprocess 93469 is still running
  _warn("subprocess %s is still running" % self.pid,
ResourceWarning: Enable tracemalloc to get the object allocation traceback
/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/subprocess.py:829: ResourceWarning: unclosed file <_io.BufferedReader name=6>
  _cleanup()
ResourceWarning: Enable tracemalloc to get the object allocation traceback
/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/subprocess.py:1137: ResourceWarning: subprocess 93470 is still running
  _warn("subprocess %s is still running" % self.pid,
ResourceWarning: Enable tracemalloc to get the object allocation traceback
E...F......
======================================================================
ERROR: test_stay_connected (logcat_color_test.LogcatColorAsyncTest.test_stay_connected)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/asyncio/base_events.py", line 720, in run_until_complete
    return future.result()
           ~~~~~~~~~~~~~^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/test/logcat_color_test.py", line 190, in test_stay_connected
    await self.lc.loop()
  File "/Users/marshall/Code/github.com/marshall/logcat-color/logcat-color", line 284, in loop
    await self.start()
  File "/Users/marshall/Code/github.com/marshall/logcat-color/logcat-color", line 280, in start
    await self.init_reader()
  File "/Users/marshall/Code/github.com/marshall/logcat-color/logcat-color", line 261, in init_reader
    line = await afp.readline()
           ^^^^^^^^^^^^^^^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/aiofile/utils.py", line 247, in readline
    chunk = await self.__read(self._READLINE_CHUNK_SIZE)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/aiofile/utils.py", line 227, in __read
    data = await self.file.read_bytes(length, self._offset)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/aiofile/aio.py", line 233, in read_bytes
    return await self.__context.read(size, self.fileno(), offset)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/caio/asyncio_base.py", line 58, in submit
    return op.get_value()
           ~~~~~~~~~~~~^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/caio/python_aio.py", line 241, in get_value
    raise self.exception
  File "/opt/homebrew/Cellar/[email protected]/3.13.1/Frameworks/Python.framework/Versions/3.13/lib/python3.13/multiprocessing/pool.py", line 125, in worker
    result = (True, func(*args, **kwds))
                    ~~~~^^^^^^^^^^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/caio/python_aio.py", line 98, in _handle_read
    self.__pread(
    ~~~~~~~~~~~~^
        operation.fileno,
        ^^^^^^^^^^^^^^^^^
        operation.nbytes,
        ^^^^^^^^^^^^^^^^^
        operation.offset,
        ^^^^^^^^^^^^^^^^^
    ),
    ^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/.venv/lib/python3.13/site-packages/caio/python_aio.py", line 79, in __pread
    return os.pread(fd, size, offset)
           ~~~~~~~~^^^^^^^^^^^^^^^^^^
OSError: [Errno 29] Illegal seek

======================================================================
FAIL: test_piped_input (logcat_color_test.LogcatColorTest.test_piped_input)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/marshall/Code/github.com/marshall/logcat-color/test/logcat_color_test.py", line 19, in wrapped
    fn(self)
    ~~^^^^^^
  File "/Users/marshall/Code/github.com/marshall/logcat-color/test/logcat_color_test.py", line 84, in test_piped_input
    self.assertEqual(self.proc.returncode, 0)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: 1 != 0

----------------------------------------------------------------------
Ran 23 tests in 0.689s

FAILED (failures=1, errors=1)

[zcattacz]

Using the above fork, I am missing a lot of messages, packages filter seldom work since ActiveityManager's Proc start message seldom got received. Below adjustment got it fixed:
in logcat-color L267:

        async with async_open(self.input, 'r', context=linux_ctx) as afp:
            async for line in afp:
                self.reader.process_line(line)

also maybe Profile.include() should check for tag==ActivityManager before process_new_pid() to save some function calls.

Anyway thank you all for making a working filterable logcat for python3. It makes the development outside of Android Studio easier.

[zcattacz]

The test.py showed all pass

...
----------------------------------------------------------------------
Ran 23 tests in 1.911s

OK

There is another issue, the adb path in config is not picked up correctly,
logcat-color L174

    def get_adb_prog(self):
        adb = "adb" # Let the system find adb on the PATH
        if "ADB" in os.environ:
            adb = os.environ["ADB"]
            return adb
        # `get_adb_devices()` also calls this but doesn't process config.
        # moved from `get_adb_args()`
        if config_adb:
            adb = config_adb
        return abd

[zcattacz]

This is not py3 related, there is another thing that's acting weird, the filters seem to get first fail win.

    def include(...):
        ...
        for filter in self.filters:
            if not filter(data):
                return False

        return True

[zcattacz]

This is not py3 related, the format is used as layout, and passed to logcat on the commandline, it seem impossible to filter by package/pid and use tag layout at the same time.