Re: [linux-lvm] Tagging LVs with Python Bindings

[Tony Asleson <tasleson@redhat.com>]

On 04/06/2015 12:08 PM, Michael Schmidt wrote:
> Hi all,
> 
> While working with the Python bindings and attempting to add tags to
> logical volume lvm_vg_write seems not to be called. This means if add_tag
> is called and the virtual group handle is closed the tags disappear. 

Thanks for reporting this!

> The
> action in _liblvm_lvm_vg_add_tag solves this by calling lvm_vg_write on the
> handle itself. Since the lv handle does not seem to have access to it's vg
> handle I added a method to the vg just to trigger a write:

The python bindings were written with the expectation that the state
changes would be saved automatically.  So adding a call for the user to
issue a write on the vg goes against the overall design.

...

> My question is: is there a better way to accomplish this?

In this case we should issue the lvm_vg_write in the add/remove tag
calls for the lv.  The lv structure has a pointer to the parent vg in
the python binding.

I submitted a patch which does this and improves the unit test to test
for this.

Any bugzilla submitted for this?

Regards,
Tony