Project: mesos
Issue MESOS-3208: Fetch checksum files to inform fetcher cache use
This is the first part of phase 1 as described in the comments for MESOS-2073. We add a field to CommandInfo::URI that contains the URI of a checksum file. When this file has new content, then the contents of the associated value URI needs to be refreshed in the fetcher cache. In this implementation step, we just add the above basic functionality (download, checksum comparison). In later steps, we will add more control flow to cover corner cases and thus make this feature more useful.
Story points: 3