Message value has payload argument that causes ide warning

[PGryllos]

Description

The returned Kafka messages value method expects an argument payload
that makes the ide mark the calling of the method as problematic. It's not a real issue but
I wonder where it stems from.

for instance

msg = consumer.poll()
process_msg_value(msg.value())

will give a warning in pycharm as if I am missing an input on the value method.

The method I find is the following

    def value(self, payload): # real signature unknown; restored from __doc__
        """
        :returns: message value (payload) or None if not available.
          :rtype: str|bytes or None
        """
        pass

How to reproduce

On pycharm (my version 2017.1) call msg.value()

Checklist

Please provide the following information:

• confluent-kafka-python and librdkafka version (confluent_kafka.version() and confluent_kafka.libversion()): 0.9.2
• Apache Kafka broker version:
• Client configuration: {...}
• Operating system: MacOS
• Provide client logs (with 'debug': '..' as necessary)
• Provide broker log excerpts
• Critical issue

[edenhill]

msg.value() is a CPython function and does not have a payload argument.
I'm not sure where you are seeing that Python method definition?

[PGryllos]

The ide finds an abstract definition of the consumer in confluent_kafka/cimpl.py

[edenhill]

Okay, I'm not sure what to make of it.
As far as I can tell the confluent_kafka module does not export a method with that signature.

[PGryllos]

My bad, the full path is

/Users/user/Library/Caches/PyCharmCE2017.1/python_stubs/160944109/confluent_kafka/cimpl.py

I am also not sure what to make out of it because I cannot find the value method signature but probably it's an pycharm error

[ShukujiNeel13]

I'm facing the exact same issue.
Python: 3.7
Package: confluent-kafka, version: 1.3.0

In fact when I navigate to the function definition (as pointed by PGryllos ) above
at the file Path /Library/Caches/PyCharm2019.2/python_stubs/-2090162168/confluent_kafka/cimpl.py
the functions in this file have a comment on the side: "real signature unknown"
Also, this particular function has more to the comment: "; restored from doc"

It seems it is specific to the IDE, since it is using an IDE specific cached file for this package...

[Lakritsbiten]

I'm facing the exact same issue.
Python: 3.7.4
Package: confluent-kafka, version: 1.5.0

[edenhill]

@Lakritsbiten What IDE are you using? Can you paste a screenshot or provide some kind of output?

[Lakritsbiten]

Sure, I am using PyCharm 2020.2.1

[debradley]

This may be a bug or limitation in PyCharm's parsing of the C source code into binary skeletons where it is forced to rely on inline docs and gets the details wrong.

[jpuskar]

This problem still exists with:

• PyCharm 2023.1.3 (Community Edition) Build #PC-231.9161.41, built on June 20, 2023
• On ARM (MacOS 12.6.5 (21G531)).
• Using confluent-kafka 2.1.1.
• Using Python 3.9.

@debradley appears to be correct per this: