Panicing if not running in a test and if the component-base/version
variables are empty is not ideal. At some point sections
of kubeadm could be exposed as a library and if these sections
import the constants package, they would panic on the library
users unless they set the version information in component-base
with ldflags.
Instead:
- If the component-base version is empty, return a placeholder version
that should indicate to users that build kubeadm that something is not
right (e.g. they did not use 'make'). During library usage or unit
tests this version should not be relevant.
- Update unit tests to use hardcoded versions instead of the versions
from the constants package. Using the constants package for testing
is good but during unit tests these versions are already placeholders
since unit tests do not populate the actual component-base versions
(e.g. 1.23).
Tests under /app and /test would fail if the current/minimum k8s version
is dynamically populated from the version in the kubeadm binary.
Adapt the tests to support that.
Kubeadm requires manual version updates of its current supported k8s
control plane version and minimally supported k8s control plane and
kubelet versions every release cycle.
To avoid that, in constants.go:
- Add the helper function getSkewedKubernetesVersion() that can be
used to retrieve a MAJOR.(MINOR+n).0 version of k8s. It currently
uses the kubeadm version populated in "component-base/version" during
the kubeadm build process.
- Use the function to set existing version constants (variables).
Update util/config/common.go#NormalizeKubernetesVersion() to
tolerate the case where a k8s version in the ClusterConfiguration
is too old for the kubeadm binary to use during code freeze.
Include unit tests for the new utilities.
This change optimizes the kubeadm/etcd `AddMember` client-side function
by stopping early in the backoff loop when a peer conflict is found
(indicating the member has already been added to the etcd cluster). In
this situation, the function will stop early and relay a call to
`ListMembers` to fetch the current list of members to return. With this
optimization, front-loading a `ListMembers` call is no longer necessary,
as this functionally returns the equivalent response.
This helps reduce the amount of time taken in situational cases where an
initial client request to add a member is accepted by the server, but
fails client-side.
This situation is possible situationally, such as if network latency
causes the request to timeout after it was sent and accepted by the
cluster. In this situation, the following loop would occur and fail with
an `ErrPeerURLExist` response, and would be stuck until the backoff
timeout was met (roughly ~2min30sec currently).
Testing Done:
* Manual testing with an etcd cluster. Initial "AddMember` call was
successful, and the etcd manifest file was identical to prior version
of these files. Subsequent calls to add the same member succeeded
immediately (retaining idempotency), and the resulting manifest file
remains identical to previous version as well. The difference, this
time, is the call finished ~2min25sec faster in an identical test in
the environment tested with.
The purell package at github.com/PuerkitoBio/purell is no longer maintained and in k/k repo under kubeadm package its been used for normalizing the URL. This commit removes the dependency on this package and creates a local function for normalizing the URL within the preflight package under cmd/kubeadm.
Signed-off-by: gkarthiks <github.gkarthiks@gmail.com>
chore: add new line at end of the file
Signed-off-by: gkarthiks <github.gkarthiks@gmail.com>
fix: remove unused mod from vendor modules file
Signed-off-by: gkarthiks <github.gkarthiks@gmail.com>
During operations such as "upgrade", kubeadm fetches the
ClusterConfiguration object from the kubeadm ConfigMap.
However, due to requiring node specifics it wraps it in an
InitConfiguration object. The function responsible for that is:
app/util/config#FetchInitConfigurationFromCluster().
A problem with this function (and sub-calls) is that it ignores
the static defaults applied from versioned types
(e.g. v1beta3/defaults.go) and only applies dynamic defaults for:
- API endpoints
- node registration
- etc...
The introduction of Init|JoinConfiguration.ImagePullPolicy now
has static defaulting of the NodeRegistration object with a default
policy of "PullIfNotPresent". Respect this defaulting by constructing
a defaulted internal InitConfiguration from
FetchInitConfigurationFromCluster() and only then apply the dynamic
defaults over it.
This fixes a bug where "kubeadm upgrade ..." fails when pulling images
due to an empty ("") ImagePullPolicy. We could assume that empty
string means default policy on runtime in:
cmd/kubeadm/app/preflight/checks.go#ImagePullCheck()
but that might actually not be the user intent during "init" and "join",
due to e.g. a typo. Similarly, we don't allow empty tokens
on runtime and error out.
Instead of dynamically defaulting NodeRegistration.ImagePullPolicy,
which is common when doing defaulting depending on host state - e.g.
hostname, statically default it in v1beta3/defaults.go.
- Remove defaulting in checks.go
- Add one more unit test in checks_test.go
- Adapt v1beta2 conversion and fuzzer / round tripping tests
This also results in the default being visible when calling:
"kubeadm config print ...".
