The function TryRunCommand() uses an exponential backoff,
which is good, but it's inconsistent and only used in a couple
of places.
Remove its usage in the token.go#UpdateOrCreateTokens()
and switch to using the standard function used in other places -
PollUntilContextTimeout().
Remove wait.go#TryRunCommand(), as there are no other usages.
The function wait.go#WaitForKubeletAndFunc() has been used in
a number of places in kubeadm. It starts a go routine to wait for
the kubelet /healthz and in parallel starts another go routine
to wait for an custom function.
This logic is problematic. If kubeadm is waiting for the kubelet
in parallel with something that requires the kubelet, the right
solution would be to first wait for the kubelet in serial and only
then proceed with the other action. The parallelism here particularly
during "init" required a unwanted "initial timeout" of 40s, before
the kubelet waiting even starts. In most cases, this makes the kubelet
waiter to not even start, while the main point of waiting becomes
the "other action".
- Remove the function WaitForKubeletAndFunc() from the Waiter interface.
- Rename the function WaitForHealthyKubelet() to just WaitForKubelet()
to be consistent with the naming WaitForAPI().
- Update WaitForKubelet() to not use TryRunCommand() and instead
use PollUntilContextTimeout().
- Remove the "initial timeout" of 40s in WaitForKubelet().
- Make both WaitForKubelet() and WaitForAPI() use similar error
handling and output.
- Update all usage of WaitForKubelet() to be a serial call before
any other action, such as another wait* call.
- Make the default wait timeout for the kubelet
/healthz to be 1 minute (kubeadmconstants.DefaultKubeletTimeout).
- Apply updates to all implementations of the Waiter interface.
Add v1beta4.ClusterConfiguration.EncryptionAlgorithm field (string)
and allow the user to configure the cluster asymetric encryption
algorithm to be either "RSA" (default, 2048 pkey size) or "ECDSA" (P-256).
Add validation and fuzzing. Conversion from v1beta3 is not required
because an empty field value is accepted and defaulted to RSA if needed.
Leverage the existing configuration option (feature gate) PublicKeysECDSA
but rename the backend fields, arguments, function names to be more
generic - EncryptionAlgorithm instead of PublicKeyAlgorithm.
That is because once the feature gate is enabled the algorithm
configuration also applies to private keys. It also uses the kubeadm API
type (string) instead of the x509.PublicKeyAlgorithm enum (int).
Deprecate the PublicKeysECDSA feature gate with a message.
It should be removed with the release of v1beta4 or maximum one release
later (it is an alpha FG).
I moved a simpler condition to the beginning of the function (when the error == nil). This has substantially streamlined the function for readability and comprehension of its logic flow.
In all places map[string]string compounds were used directly
for extra args. Modify said locations to use []Arg
and the new utilities Get/SetArgValue(), ArgumentsTo/FromCommand().
Use []kubeadm.Arg instead of map[string]string when
validating ExtraArgs in the API.
Add new GetArgValue() and SetArgValue() utilities
and tests in apis/kubeadm.
Add new utils for constucting commands from and to
a []kubeadm.Arg slice.
