During rendering, RenderableNodes are created by Map funcs, which take only
NodeMetadata. Previously, it was simply assumed that the relevant keys for a
given Map func would be present in the metadata. If that implicit invariant
failed, the returned RenderableNode would be invalid, with e.g. an ID of
"hostid::". That, in turn, would trigger undefined behavior later on in the
rendering workflow.
This bug was detected by creating a partial node metadata for a non-local
endpoint node. That node was detected during the first phase of rendering, and
given an invalid renderable node ID of "myhostname::", which prevented it from
attaching to TheInternet pseudonode. It eventually got removed from the set
of valid nodes, which meant nodes that were adjacent to it suddenly became
orphans, and got filtered out by the FilterUnconnected step of the rendering
pipeline.
With this change, every map func checks for the presence of mandatory fields,
i.e. the fields that compose the resulting renderable node's ID.
Also,
- Add unit tests for LeafMapFuncs
- Topology Validate checks NodeMetadatas must not have nil Metadata
NewNodeMetadata -> MakeNodeMetadata. It doesn't return a pointer, so
Make is more idiomatic.
Invoke MakeNodeMetadata when necessary. The zero value for a
NodeMetadata is no longer valid.
Split MakeNodeMetadata to two constructors. MakeNodeMetadata when you
don't have anything to prepopulate; MakeNodeMetadataWith when you do.
Also, a fix to the tests in app. We unmarshal a RenderableNode struct,
which has a JSON-ignored NodeMetadata field. The zero value is invalid,
so we need to fix that before performing comparisons.
This fixes the regression where process names weren't appearing for
Darwin probes. Makes testing easier.
Also, changes the process walker to operate on value types. There's no
performance advantage to using reference types for something of this
size, and there appeared to be a data race in the Darwin port that
caused nodes to gain and lose process names over time.
Also, restructures how to enable docker scraping. Default false when run
manually, and enabled via --probe.docker true in the scope script.
- Make poll take interfaces, do diff on error
- Use poll in TestRegistryEvents
- Improve the locking to prevent deadlocks and data races in registry_test.go
