[Libguestfs] Shebang sh plugins (was: Re: [PATCH nbdkit v2 03/10] python: Implement nbdkit API version 2.)

[Richard W.M. Jones]

On Sun, Nov 24, 2019 at 03:31:35PM +0200, Nir Soffer wrote:
> But the imageio plugin is not a script you can run, and if you want to
> make it a standalone tool it needs a lot of work that is not related to virt-v2v
> like adding command line parsing or dealing with file formats.
> 
> Such tool mostly already exists in ovirt sdk examples:
> https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/upload_disk.py
> 
> So for rhv-upload there is no use case for standalone script.

Sure, not right now, but what I'm saying is that a standalone imageio
plugin would be possible.

> > So that's the use case (which to be fair is not actually used much
> > today at all).  The context above is I can't think of a way to extend
> > this feature to nbdkit-sh-plugin.
> 
> But today we require the plugin name in nbdkit command line:
> 
>     ./nbdkit -f -v python zero.py
> 
> It could be nice to be able to do:
> 
>     ./nbdkit -f -v zero.py

No need because with shebang scripts you can do:

  ./zero.py [-f] [-v] [params ...]

and for Python plugins this works today.  (It doesn't work with
nbdkit-sh-plugin.)

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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