Re: [RFC/PATCH] shell: allow 'help' command to disable interactive shell

[Junio C Hamano <gitster@pobox.com>]

Jonathan Nieder <jrnieder@gmail.com> writes:

> Junio C Hamano wrote:
>
>> The purpose of the directory is to keep custom commands that are
>> allowed.  If the site administrator does not want any command, it
>> would be more natural to expect that the way to disable them would
>> be _not_ to have that directory which is a collection of allowed
>> commands.  Adding that directory and add a "help" that exits with
>> non-zero feels quite a roundabout and counter-intuitive way, no?
>
> I think it comes down to the reason the site admin doesn't want to
> allow interactive logins.  That reason seems to be mostly that
> presenting a
>
> 	git>
>
> prompt at which you can only ask for "help" or "exit" is a bit
> confusing and pointless.  I have sympathy for that, which is why I
> looked for a way for the admin to ask to avoid the prompt altogether
> in that case.

Yeah, the prompt does look pointless.

> I do not think the reason is "because I don't want a
> git-shell-commands directory".  I think it's good to have basically
> one kind of setup instead of significantly different ones with and
> without that special directory --- and it means that starting from a
> setup like this, one can easily drop in additional commands like
> set-head or create-repo without changing anything basic.  It's making
> the admin's later life easier.

I do not think I follow.  If the admin wants to eventually have
extra commands supported at the site, but not yet ready to do so,
isn't it more natural to start with a less elaborate configuration
(i.e. without the directory) now and then add the directory when the
site is ready for offering extra commands later?

> Maybe a better test than "help exits with special exit code" is "there
> are no other custom commands than help".  Would that be more sensible?
>
> From a "make it possible to emulate gitolite" point of view, that
> doesn't permit disabling the interactive mode when there are other
> commands available, so my hunch is that it wouldn't.

A paragraph I had in the message you are responding to before I sent
it out (but removed because it felt somewhat offtopic) said "if the
mechanism to disable weren't the magic 'help exited with failure'
but 'an interactive-disabled flag file exists there', I may find it
less strange to have the directory there", or something like that.

And that flag file could be a custom script that gives a custom
message.