A while back we added a "StatsReporter" argument to `controller.NewImpl`,
but in serving every callsite of this is passing:
```
controller.NewImpl(r, logger, "my-string", MustNewStatsReporter("my-string", logger))
```
Where `MustNewStatsReporter` is just a form of knative/pkg's `controller.NewStatsReporter`
that logs fatally when an error is returned. It is notable that Serving's logic has been
duplicated to both Build and Eventing.
There are a handful of changes here:
1. Move MustNewStatsReporter into knative/pkg
2. Expose the current interface as NewImplWithStats
3. Drop the StatsReporter from NewImpl and default to `MustNewStatsReporter()`
This is a breaking change for downstream repositories, but should make their callsites universally simpler.
In serving we have `reconciler.Handler` that wraps a handler function
(e.g. `Enqueue`) in the `cache.ResourceEventHandlerFuncs`. This pattern
was becoming pervasive, so this simpler handler dramatically reduced our
boilerplate.
This is needed for the positive handoff, so that we can enqueue
the KPA after we received the positive answer from the activator
but still want to have buffer time to make sure the network
changes propagate everywhere.
* Add a version of GlobalResync that calls an event handler.
This allows impl to apply filtering and queuing logic of their own,
instead of calling Enqueue() for everything.
* Fix typo in doc comment.
I was hoping to switch from a simple string key to a struct to include additional metadata into our workqueue item (in particular the time at which it was queued), but the great unit tests here reminded me that this would not properly deduplicate keys (they would have different queue times!), so I'm settling for simplifying the loop in a few ways:
1. Keys can only be strings, so remove some error checking and a test.
1. We were wrapping a block in a `func` because it contained `defer`, but the outer function had nothing in it.
I'd still like to try and find a way to track queue times for keys, so that we can surface two interesting metrics:
1. How long are things spending queued?
1. How long between events being observed and us responding? (above + reconcile latency)
* Prepare for global resync on ConfigMap changes
- Add GlobalResync(cache.SharedInformer) method to *controller.Impl
- Move UntypedStore from serving/pkg/config to pkg/configmap
- Add onAfterStore callbacks to UntypedStore
- Add TypeFilter to enable composable construction of such callbacks
* Address review
- Unit test GlobalResync()
- Reimpl GlobalResync() using ListKeys()
* Update comments
* Add test for onAfterStore
* Update godoc comment for Logger
The rate limiting queue makes the sleep necessary. Locally I see 0-2 failures when this is run with -count=10000. This bumps the sleep slightly to reduce this further.
Fixes: https://github.com/knative/pkg/issues/56
The `controller.go` is from: https://github.com/knative/serving/pull/1770, however, this adds 100% coverage of `controller.go`, which we have been missing in `knative/serving`.
This also adds a `context.Context` to the `Reconcile` signature, to enable better sharing of logger setup across controllers.
Fixes: https://github.com/knative/pkg/issues/8