Empty string doesn't set fields when using ini-config:localrc_set

[Michael Turek]

This could be intended behavior but I figured I'd still open the bug.

If an empty string is passed as the value of a field, it does not indicate such in the local.conf

For example:

localrc_set /home/stack/devstack/local.conf ML2_L3_PLUGIN ''

cat /home/stack/devstack/local.conf | grep ML2_L3_PLUGIN

The value isn't there. A workaround is to use ' ' as the argument. Let me know if you'd like more info.

[Dr. Jens Harbott (j-harbott)]

It looks to me as if this is working as designed, please explain your use case in more detail if you think otherwise.

[Michael Turek (mjturek)]

Hello j-harbott,

So it's obviously been a while since we hit this, but I believe the rationale was that we were trying to override the default value of the ML2_L3_PLUGIN to be empty as we did not want to load any ML2 plugin. It was causing the creation of some neutron resources that we didn't want [0].

So we decided to use localrc_set in our pre-test-hook to wipe out the value. An empty string seemed like an appropriate value to do this, but instead we needed a single space.

Let me know if you need more info. Thanks!

[0] https://etherpad.openstack.org/p/IronicThirdPartyGateDebugging

[Dr. Jens Harbott (j-harbott)]

The reason for this seems that there is this guard against empty arguments here:

http://git.openstack.org/cgit/openstack-dev/devstack/tree/inc/ini-config#n406

So from looking at that code this is the expected behaviour. Is there some problem with using a space or similar value as parameter? Or do you just think that this behaviour should be better documented?

[Dr. Jens Harbott (j-harbott)]

Actually I think that we could place a check into localrc_set to generate a warning or maybe an error there.

[Michael Turek (mjturek)]

Sounds good to me! But unless what we did was not valid (empty value for an option), I would like if there was a documented way of providing empty values for options.

Thanks!