[Libguestfs] [PATCH] v2v: -o rhv-upload: decouple name of nbdkit python plugin

[Richard W.M. Jones]

On Thu, Dec 13, 2018 at 06:58:30PM +0100, Pino Toscano wrote:
> Do not assume that the Python plugin of nbdkit has the same name of the
> Python interpreter.
> 
> Use the default upstream name of nbdkit to identify it; downstream
> distributions must adjust this variable, in case they rename the Python
> plugin of nbdkit.

I'm not saying this is wrong, but it does break "out of the box" -o
rhv-upload.  It means that to get it to work on Fedora we _have_ to
patch:

> --- a/v2v/output_rhv_upload.ml
> +++ b/v2v/output_rhv_upload.ml
> @@ -78,6 +78,7 @@ let parse_output_options options =
>  
>    { rhv_cafile; rhv_cluster; rhv_direct; rhv_verifypeer }
>  
> +let nbdkit_python_plugin = "python"

to change this "python3" [1].

I would dearly love to drop Python 2 support everywhere, but I don't
think we can do that realisticly before the Python 2 EOL
(https://pythonclock.org/) which is another 12 months away.

I wonder if there's a better way we can solve this?  I don't have any
immediate ideas ...

Rich.


[1] By the way, the failure is weird, non-obvious and non-actionable,
so here it is:

nbdkit python '/home/rjones/d/libguestfs-master/tmp/v2v.xSFDLk/rhv-upload-plugin.py' --dump-plugin >/dev/null
  File "/home/rjones/d/libguestfs-master/tmp/v2v.xSFDLk/rhv-upload-plugin.py", line 3
SyntaxError: Non-ASCII character '\xe2' in file /home/rjones/d/libguestfs-master/tmp/v2v.xSFDLk/rhv-upload-plugin.py on line 3, but no encoding declared; see http://python.org/dev/peps/pep-0263/ for details
nbdkit: error: /home/rjones/d/libguestfs-master/tmp/v2v.xSFDLk/rhv-upload-plugin.py: error running this script
virt-v2v: error: nbdkit python plugin is not installed or not working.  It 
is required if you want to use ‘-o rhv-upload’.


-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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