This does not providepasscmd as a fallback tokey, in the configuration file, but only appears to replace it? Running this PR/branch with current zulip-termmain causes a crash, since my default zuliprc does not contain apasscmd, but only akey. You can reproduce this by entering the zulip-term virtual environment and installing the/zulip/ package folder in editable (-e) mode.

Also see my comment here:zulip/zulip-terminal#1581 (comment)
(while that comment applied to the documentation, this applies just as much to the code)

I'd suggest we don't need this to be a method that looks developer-facing, and it could likely be placed inline directly in the code above where it would be otherwise called.

That said:

• You're currently returningOptional[str], but I don't see where that can happen; it's unclear to me why the type-checker isn't complaining about that
• RuntimeError is a very broad exception; if we're to use an exception here, or differently if this is inlined, I'd suggest it should be more specific
• The returncode appears not to be portable across platforms;run can provide another solution, I believe?
• While we rely on a user to know what they are doing when using passcmd, I would suggest that the simpler commands we accept, and/or the more checking of the command we can do, the better.

now look at the changes and give the feedback

Minor: This seems used only for thepasscmd case, not all API key retrieval? If so, the name could be improved.

Note for later review: I'm unsure what behavior we want here, ie. whether we should allowpasscmd to overridekey in the config file.

have a look at thiszulip/zulip-terminal#1581 (comment) ,If either passcmd or api is present in the configuration file, the application will use whichever is available. This line specifically checks whether passcmd is present in the configuration.

Sure. The current change allows for both to be present in the file, and my point is whether only one or the other should be present, to make it clearer what the outcome should be.

I'll defer to Tim as to if we'll want apasscmd option to the initializer.

However, with the current code below, the behavior appears incorrect, if we intend to support this behavior.

Nit: This formatting looks strange and long.

the first block handles parsing the passcmd using shlex.split(), raising an APIKeyRetrievalError if parsing fails.

• It then runs the parsed command securely using subprocess.run() with error checking.
• If the command fails (non-zero return code), a descriptive APIKeyRetrievalError is raised with details.

What's the basis for this approach? Do you have a reference?

If passcmd contains any of these characters, it may lead to command injection, potentially resulting in unexpected behavior.

I understand that this is the intent, but if having something like this then it would be good to have a reference that these are a definitive list to use, or alternatively perform the inverse, ie. scan for what is expected to be valid.