* The linkerd proxy does not work with headless services (i.e. endpoints not referencing a pod).
Changed endpoints_watcher to also return endpoints with no targetref.
Fixes#3308
Signed-off-by: Johannes Hansen <johannesh1980@gmail.com>
* Fix panic in endpoint_translator
Signed-off-by: Johannes Hansen <johannesh1980@gmail.com>
* Avoid the dashboard requesting stats when not needed
Create an alternative to `urlsForResource` called
`urlsForResourceNoStats` that makes use of the `skip_stats` parameter in
the stats API (created in #1871) that doesn't query Prometheus when not needed.
When testing using the dashboard looking at the linkerd namespace,
queries per second went down from 2874 to 2756, a 4% decrease.
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
* Have the proxy-injector emit events upon injection/skipping injection
Fixes#3253
Have the proxy-injector emit an event whenever a injection happens, or
when injection is skipped for some reason (also added that reason into
the proxy-injector logs). The level is associated to the parent workload
(it can't be associated to the pod because at this point the pod hasn't
been persisted).
The event recorder was setup at the `webhook/server.go` level and passed
to the proxy-injector's `Inject` function. The sp-validator thus also
has access to the event recorder, but for now it's not using it.
Related changes:
- Refactored `api.GetOwnerKindAndName()` to have it return a more
generic object.
- Refactored `report.Injectable()` to also have it return the reason why
a workload is not injectable.
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
Fixes https://github.com/linkerd/linkerd2/issues/2800#issuecomment-513740498
When the Linkerd proxy sends a query for a Kubernetes external name service to the destination service, the destination service returns `NoEndpoints: exists=false` because an external name service has no endpoints resource. Due to a change in the proxy's fallback logic, this no longer causes the proxy to fallback to either DNS or SO_ORIG_DST and instead fails the request. The net effect is that Linkerd fails all requests to external name services.
We change the destination service to instead return `InvalidArgument` for external name services. This causes the proxy to fallback to SO_ORIG_DST instead of failing the request.
Signed-off-by: Alex Leong <alex@buoyant.io>
The destination service's endpoints watcher assumed every `Endpoints`
object contained a `TargetRef`. This field is optional, and in cases
such as the default `ep/kubernetes` object, `TargetRef` is nil, causing
a nil pointer dereference.
Fix endpoints watcher to check for `TargetRef` prior to dereferencing.
Signed-off-by: Andrew Seigner <siggy@buoyant.io>
We add support for looking up individual pods in a stateful set with the destination service. This allows Linkerd to correctly proxy requests which address individual pods. The authority structure for such a request is `<pod-name>.<service>.<namespace>.svc.cluster.local:<port>`.
Fixes#2266
Signed-off-by: Alex Leong <alex@buoyant.io>
To give better visibility into the inner workings of the kubernetes watchers in the destination service, we add some prometheus metrics.
Signed-off-by: Alex Leong <alex@buoyant.io>
* Have `GetOwnerKindAndName` be able to skip the cache
Refactored `GetOwnerKindAndName` so it can optionally skip the
shared informer cache and instead hit the k8s API directly.
Useful for the proxy injector, when the pod's replicaset got just
created and might not be in ready in the cache yet.
Fixes#2738
Signed-off-by: Alejandro Pedraza <alejandro@buoyant.io>
This is a major refactor of the destination service. The goals of this refactor are to simplify the code for improved maintainability. In particular:
* Remove the "resolver" interfaces. These were a holdover from when our decision tree was more complex about how to handle different kinds of authorities. The current implementation only accepts fully qualified kubernetes service names and thus this was an unnecessary level of indirection.
* Moved the endpoints and profile watchers into their own package for a more clear separation of concerns. These watchers deal only in Kubernetes primitives and are agnostic to how they are used. This allows a cleaner layering when we use them from our gRPC service.
* Renamed the "listener" types to "translator" to make it more clear that the function of these structs is to translate kubernetes updates from the watcher to gRPC messages.
Signed-off-by: Alex Leong <alex@buoyant.io>