* Separate observability API
Closes#5312
This is a preliminary step towards moving all the observability API into `/viz`, by first moving its protobuf into `viz/metrics-api`. This should facilitate review as the go files are not moved yet, which will happen in a followup PR. There are no user-facing changes here.
- Moved `proto/common/healthcheck.proto` to `viz/metrics-api/proto/healthcheck.prot`
- Moved the contents of `proto/public.proto` to `viz/metrics-api/proto/viz.proto` except for the `Version` Stuff.
- Merged `proto/controller/tap.proto` into `viz/metrics-api/proto/viz.proto`
- `grpc_server.go` now temporarily exposes `PublicAPIServer` and `VizAPIServer` interfaces to separate both APIs. This will get properly split in a followup.
- The web server provides handlers for both interfaces.
- `cli/cmd/public_api.go` and `pkg/healthcheck/healthcheck.go` temporarily now have methods to access both APIs.
- Most of the CLI commands will use the Viz API, except for `version`.
The other changes in the go files are just changes in the imports to point to the new protobufs.
Other minor changes:
- Removed `git add controller/gen` from `bin/protoc-go.sh`
Currently, Each new instance of `Checker` type have to manually
set all the fields with the `NewChecker()`, even though most
use-cases are fine with the defaults.
This branch makes this simpler by using the Builder pattern, so
that the users of `Checker` can override the defaults by using
specific field methods when needed. Thus simplifying the code.
This also removes some of the methods that were specific to tests,
and replaces them with the currently used ones.
Signed-off-by: Tarun Pothulapati <tarunpothulapati@outlook.com>
## What
This change moves the `linkerd check --multicluster` functionality under it's
own multicluster subcommand: `linkerd multicluster check`.
There should be no functional changes as a result of this change. `linkerd
check` no longer checks for anything multicluster related and the
`--multicluster` flag has been removed.
## Why
Closes#5208
The bulk of these changes are moving all the multicluster checks from
`pkg/healthcheck` into the multicluster package.
Doing this completely separates it from core Linkerd. It still uses
`pkg/healtcheck` when possible, but anything that is used only by `multicluster
check` has been moved.
**Note the the `kubernetes-api` and `linkerd-existence` checks are run.**
These checks are required for setting up the Linkerd health checker. They set
the health checker's `kubeAPI`, `linkerdConfig`, and `apiClient` fields.
These could be set manually so that the only check the user sees is
`linkerd-multicluster`, but I chose not to do this.
If any of the setting functions errors, it would just tell the user to run
`linkerd check` and ensure the installation is correct. I find the user error
handling to be better by including these required checks since they should be
run in the first place.
## How to test
Installing Linkerd and multicluster should result in a basic check output:
```
$ bin/linkerd install |kubectl apply -f -
..
$ bin/linkerd check
..
$ bin/linkerd multicluster install |kubectl apply -f -
..
$ bin/linkerd multicluster check
kubernetes-api
--------------
√ can initialize the client
√ can query the Kubernetes API
linkerd-existence
-----------------
√ 'linkerd-config' config map exists
√ heartbeat ServiceAccount exist
√ control plane replica sets are ready
√ no unschedulable pods
√ controller pod is running
√ can initialize the client
√ can query the control plane API
linkerd-multicluster
--------------------
√ Link CRD exists
Status check results are √
```
After linking a cluster:
```
$ bin/linkerd multicluster check
kubernetes-api
--------------
√ can initialize the client
√ can query the Kubernetes API
linkerd-existence
-----------------
√ 'linkerd-config' config map exists
√ heartbeat ServiceAccount exist
√ control plane replica sets are ready
√ no unschedulable pods
√ controller pod is running
√ can initialize the client
√ can query the control plane API
linkerd-multicluster
--------------------
√ Link CRD exists
√ Link resources are valid
* k3d-y
√ remote cluster access credentials are valid
* k3d-y
√ clusters share trust anchors
* k3d-y
√ service mirror controller has required permissions
* k3d-y
√ service mirror controllers are running
* k3d-y
× all gateway mirrors are healthy
probe-gateway-k3d-y.linkerd-multicluster mirrored from cluster [k3d-y] has no endpoints
see https://linkerd.io/checks/#l5d-multicluster-gateways-endpoints for hints
Status check results are ×
```
Signed-off-by: Kevin Leimkuhler <kevin@kleimkuhler.com>
Alejandro Pedraza
Tarun Pothulapati
Kevin Leimkuhler