- Name the function GetConfigMapWithShortRetry to be
easier to understand that the function is with a very short timeout.
Add note that this function should be used in cases there is a
fallback to local config.
- Apply custom hardcoded interval of 50ms and timeout of 350ms to it.
Previously the fucntion used exp backoff with 5 steps up to ~340ms.
Switch to PollUntilContextTimeout() everywhere to allow
usage of the exposed timeouts in the kubeadm API. Exponential backoff
options are more difficult to expose in this regard and a bit too
detailed for the common user - i.e. have "steps", "factor" and so on.
Replace the usage of the deprecated wait.Poll() and
wait.PollImmediate() functions with wait.PollUntilContextTimeout().
Since we don't have piping of context around kubeadm,
use context.Background() everywhere.
Some wait.Poll() functions were converted to "immediate" as there
is no point for them to not be. This is done for consistency.
Replace the only instance of wait.JitterUntil with
wait.PollUntilContextTimeout. JitterUntil is not deprecated
but this is also done for consistency.
Currently, timeouts are only accessible if a kubeadm runtime.Object{}
like InitConfiguration is passed around.
Any time a config is loaded or defaulted, store the Timeouts
structure in a thread-safe way in the main kubeadm API package
with SetActiveTimeouts(). Optionally, a deep-copy can be
performed before calling SetActiveTimeouts(). Make this struct
accessible with GetActiveTimeouts(). Ensure these functions
are thread safe.
On init() make sure the struct is defaulted, so that unit
tests can work with these values.
When upconverting from v1beta3 to v1beta4, it appears there is no
easy way to migrate some of the timeout values such as:
ClusterConfiguration.APIServer.TimeoutForControlPlane
to a new location:
InitConfiguration.Timeouts.<some-timeout-field>
Yes, the internal InitConfiguratio does embed a ClusterConfiguration,
but during conversion the ClusterConfiguration is converted from an
empty source.
K8s' API machinery has ways to register custom conversion functions,
such as v1beta3.ClusterConfiguration -> internal.InitConfiguration,
but these must be triggered explicitly with a decoder.
The overall migration of fields seems very awkward.
There might be hacks around that, such as storing intermediate state,
while trying to make the fuzzer rountrip happy, but instead
mutation functions can be implemented for the internal types when
calling kubeadm's migrate code. This seems much cleaner.
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.
