[Engine-devel] FeatureSupported and compatibility versions

Hi all, The current mechanism in oVirt to check whether a feature is supported in a particular compatibility version is to use the FeatureSupported class. e.g. FeatureSupported.networkLinking(getVm().getVdsGroupCompatibilityVersion()) Checks whether the "network linking" feature is supported for the the VM's cluster compatibility version. This internally checks whether the value of the corresponding config (NetworkLinkingSupported) for the given compatibility version is true/false. I'm not sure if this is a good idea, since a feature is typically supported "from" a particular version. E.g. Gluster support was introduced in 3.1, and it continues to be available in all subsequent versions. So I see no point in adding configuration for every version indicating whether the feature is supported in that version or not. I suggest to use either of the following options: 1) Instead of using a boolean config for each version, use a single string config that indicates the "supported from" version e.g. GlusterSupportedFrom = 3.1. There could be rare cases where a feature, for some reason, is removed in some release. In such cases, we could use one additional config for the "supported to" version. 2) Continue with the boolean approach, but do not have entries for every version; rather make use of the "default value" for majority of cases, and add the explicit version mapping for the minority e.g. GlusterSupported = true by default, and false in case of 3.0 (only one config required for 3.0) Thoughts? Regards, Shireesh