- Move docker probe code into it's own module
- Put PIDTree behind and interface for mocking
- Disaggregate dockerTagger into a registry, tagger and reporter
- Similarly disaggregate tests
- Add mocks for docker container and registry
- Add test for docker events & stats
This makes container image details show the containers (and processes) correctly.
Also:
- introduces a 'test' package, moved Diff function there.
- adds some tests for this new rendered view.
We only want to scope (i.e. prefix with hostID) those addresses that are
deemed loopback, to disambiguate them. Otherwise, we want to leave
addresses in unscoped form, so they can be matched, and links between
communicating nodes properly made.
So, we make the isLoopback check in MakeAddressID, and omit hostID if
the address isn't loopback. So far so good.
But this breaks topology rendering, as we were relying on extracting
hostID from adjacency node IDs, to populate origin hosts in the rendered
node output. So we need another way to get origin host from an arbitrary
node.
A survey revealed no reliable way to get that information from IDs in
their new form. However, we have access to node metadata, so this
changeset introduces the OriginHostTagger, which tags each node with its
origin host, via the foreign-key semantics we'll use going forward.
