Improve the plugin's behavior when multiple OVAs are detected: powered off OVAs

[wjun]

@wjun commented on Thu Aug 23 2018

For 1.4.3, do not attempt to connect to OVAs which are not powered on. Display a clear error message if OVAs are present, but none are powered on.

This involves changes to the plugin's OVA lookup logic, changes to the plugin's error handling, and additional tests.

[zjs]

Marking serious as this may also affect upgrade workflows, where an old, powered off OVA may still exist.

[zhoumeina]

@lweitzman , could you please design this?

[zjs]

Marking as need info: we need to confirm whether this is required for 1.4.3.

[wjun]

@zjs According to the sorting algorithm at https://github.com/vmware/vic-ui/blob/586ed3f14d95bdd302baebcfd8911c56ecfe0b3a/h5c/vic-service/src/main/java/com/vmware/vic/PropFetcher.java#L451 UI will put the latest build number in the list and use it. So it should be fine leave it out of 1.4.3, and depending on the use cases, we may prioritize if using a select list in the future release.

[zjs]

@wjun: Ah, I see. The sorting algorithm suffers from the same issue as some of our other code that looks at version numbers: it assumes a build with a higher drone job number is a newer version than a build with a lower drone job number. (Which isn't always true.) However, it should be an acceptable assumption for released builds for now; customers who use only released builds shouldn't be able to encounter the issue that I hit.