object NoneType can't be used in 'await' expression

[dmkusner]

Whenever I try to use adlfs version 2024.4.1 (only version I've ever used) my code works but on exit/cleanup it generates the following stack trace:

Traceback (most recent call last):
File "/usr/lib/python3.10/weakref.py", line 667, in _exitfunc
f()
File "/usr/lib/python3.10/weakref.py", line 591, in call
return info.func(*info.args, **(info.kwargs or {}))
File "/home/david_kusner/dmk_python/lib/python3.10/site-packages/fsspec/asyn.py", line 103, in sync
raise return_result
File "/home/david_kusner/dmk_python/lib/python3.10/site-packages/fsspec/asyn.py", line 56, in _runner
result[0] = await coro
File "/home/david_kusner/dmk_python/lib/python3.10/site-packages/adlfs/utils.py", line 78, in close_credential
await file_obj.credential.close()
TypeError: object NoneType can't be used in 'await' expression

Here is some sample code that exhibits this issue. It also happens if I acquire an AzureBlobFileSystem and work with that. Note that code works -- I can read the file and print out its contents. The stack trace occurs immediately afterwards. I haven't found any way to supress it. I'm not using any async here, so not sure why an 'await' is involved.

import fsspec
from azure.identity import AzureCliCredential
from adlfs import AzureBlobFileSystem

creds = AzureCliCredential()
storage_options = {"credential": creds}

adlFile = "abfss://[email protected]/work/dkusner/foo.txt"

with fsspec.open(adlFile, **storage_options) as f:
print(f.read())

[dmkusner]

Saw a suggestion to use azure.identity.aio library in issue #431, which I did with success. Stack trace no longer happens with async AzureCliCredential.

[mhtrinh]

I am no expert to async, but when removing the await here:

adlfs/adlfs/utils.py

Line 78 in 5c24b2e

await file_obj.credential.close()

it solved the issue ...

[TomAugspurger]

Closing in favor of #431.