Documentation is added in several areas:
1. `kubectl plugin` now prints a note that plugins are best discovered
with krew.dev and how to install it.
2. The kubectl book now has a new section about plugins, featuring
- a very brief introduction to the kubectl plugin mechanism
- a section about krew
We don't want to set the name directly because then starting the pod
can fail when the node is temporarily out of resources
(https://github.com/kubernetes/kubernetes/issues/87855).
For CSI driver deployments, we have three options:
- modify the pod spec with custom code, similar
to how the NodeSelection utility code does it
- add variants of SetNodeSelection and SetNodeAffinity which
work with a pod spec instead of a pod
- change their parameter from pod to pod spec and then use
them also when patching a pod spec
The last approach is used here because it seems more general. There
might be other cases in the future where there's only a pod spec that
needs to be modified.
A previous PR replaced the usage of Redis in the guestbook app test
with Agnhost. The replacement went well for Linux setups and Containers,
which is why the tests are green, but there is a network particularity on
Windows setups which won't allow the test to pass.
The issue was observed with another test hitting the same issue:
https://github.com/kubernetes/kubernetes/issues/83072
Here's exactly what happens during the test:
- frontend containers are created, having the /guestbook endpoint. Its main
purpose is to forward the call to either agnhost-master (cmd=set), or
agnhost-slave (cmd=get).
- agnhost-master container is created, having the /set endpoint, and the
/register endpoint, through which the agnhost-slave containers would
register to it. Its purpose is to propagate all data received through /set
to its clients.
- agnhost-slave containers are created, having the /set and /get endpoints.
They would register to agnhost-master, and then receive any and all updates
from it, which was then served through the /get endpoint.
For simplicity, all 3 types have the same agnhost subcommand (agnhost guestbook), being
able to satisfy its given purpose. For this, HTTP servers were being used, including
for the /register endpoints. agnhost-master would send its /set updates as /set HTTP
requests. However, because of the issue listed above, agnhost-master did not receive
the client's IP, but rather the container host's IP, resulting in the request being
sent to the wrong destination.
This PR updates the agnhost guestbook subcommand. Now, the agnhost subscriber nodes will
send their own IP to the /register endpoint (/endpoint?host=myip).
This commit removes AlgorithmSource from the v1alpha2 scheduler ComponentConfig api.
It also creates the necessary manual conversion functions and updates defaulting to accept the change.