Allow specifying additional tenants for sharing OpenStack images.

[clstokes]

When building an OpenStack image using Packer, the resulting image is available only to the tenant (or project) that was specified in the builder. Additional tenant ids should be able to be set (optionally) to share the resulting image with multiple tenants. This is functionally equivalent to the ami_users option for the amazon-ebs builder.

[rickard-von-essen]

@varikin Do you know if this requires Glance support?

[varikin]

@rickard-von-essen I would assume so, but I am haven't looked at that functionality. We are happy with just making images public to all projects (tenants).

[mwhooker]

looks like the API is here https://github.com/rackspace/gophercloud/blob/HEAD/openstack/imageservice/v2/members/requests.go

which is an api call against glance, so it would be required. It's been a few years since I've worked with openstack, so I'm not sure if glance is common to all infrastructures.

we'll have to update the library at a minimum. The version we're using has been deprecated, so it might be worth taking a look at the new version (https://github.com/gophercloud/gophercloud/) and seeing if it's drop-in replaceable.

[mwhooker]

@clstokes 0.12.0 will come out next week and we'll get this in immediately after in 0.12.1 before 1.0

[clstokes]

Thanks Matt!

[rickard-von-essen]

@mwhooker Could you also look into throwing in a option for visibility, private or public. See
https://github.com/rackspace/gophercloud/blob/master/openstack/imageservice/v2/images/requests.go

[mwhooker]

There's a PR for upgrading the library here, but it looks like some functionality will be lost #4211