Over the course of recent development of the `componentconfigs` package,
it became evident that most of the tests in this package cannot be implemented without
using a component config. As all of the currently supported component configs are
external to the kubeadm project (kubelet and kube-proxy), practically all of the tests
in this package are now dependent on external code.
This is not desirable, because other component's configs may change frequently and
without much of a notice. In particular many configs add new fields without bumping their
versions. In addition to that, some components may be deprecated in the future and many
tests may use their configs as a place holder of a component config just to test some
common functionality.
To top that, there are many tests that test the same common functionality several times
(for each different component config).
Thus a kubeadm managed replacement and a fake test environment are introduced.
The new test environment uses kubeadm's very own `ClusterConfiguration`.
ClusterConfiguration is normally not managed by the `componentconfigs` package.
It's only used, because of the following:
- It's a versioned API that is under the control of kubeadm maintainers. This enables us to test
the componentconfigs package more thoroughly without having to have full and always up to date
knowledge about the config of another component.
- Other components often introduce new fields in their configs without bumping up the config version.
This, often times, requires that the PR that introduces such new fields to touch kubeadm test code.
Doing so, requires more work on the part of developers and reviewers. When kubeadm moves out of k/k
this would allow for more sporadic breaks in kubeadm tests as PRs that merge in k/k and introduce
new fields won't be able to fix the tests in kubeadm.
- If we implement tests for all common functionality using the config of another component and it gets
deprecated and/or we stop supporting it in production, we'll have to focus on a massive test refactoring
or just continue importing this config just for test use.
Thus, to reduce maintenance costs without sacrificing test coverage, we introduce this mini-framework
and set of tests here which replace the normal component configs with a single one (`ClusterConfiguration`)
and test the component config independent logic of this package.
As a result of this, many of the older test cases are refactored and greatly simplified to reflect
on the new change as well. The old tests that are strictly tied to specific component configs
(like the defaulting tests) are left unchanged.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
This change enables kubeadm upgrade plan to print a state table with
information regarding known component config API groups. Most importantly this
information includes current and preferred version for each group and an
indication if a manual user upgrade is required.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Until now, users were always asked to manually convert a component config to a
version supported by kubeadm, if kubeadm is not supporting its version.
This is true even for configs generated with older kubeadm versions, hence
getting users to make manual conversions on kubeadm generated configs.
This is not appropriate and user friendly, although, it tends to be the most
common case. Hence, we sign kubeadm generated component configs stored in
config maps with a SHA256 checksum. If a configs is loaded by kubeadm from a
config map and has a valid signature it's considered "kubeadm generated" and if
a version migration is required, this config is automatically discarded and a
new one is generated.
If there is no checksum or the checksum is not matching, the config is
considered as "user supplied" and, if a version migration is required, kubeadm
will bail out with an error, requiring manual config migration (as it's today).
The behavior when supplying component configs on the kubeadm command line
does not change. Kubeadm would still bail out with an error requiring migration
if it can recognize their groups but not versions.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
kubeadm's current implementation of component config support is "kind" centric.
This has its downsides. Namely:
- Kind names and numbers can change between config versions.
Newer kinds can be ignored. Therefore, detection of a version change is
considerably harder.
- A component config can have only one kind that is managed by kubeadm.
Thus a more appropriate way to identify component configs is required.
Probably the best solution identified so far is a config group.
A group name is unlikely to change between versions, while the kind names and
structure can.
Tracking component configs by group name allows us to:
- Spot more easily config version changes and manage alternate versions.
- Support more than one kind in a config group/version.
- Abstract component configs by hiding their exact structure.
Hence, this change rips off the old kind based support for component configs
and replaces it with a group name based one. This also has the following
extra benefits:
- More tests were added.
- kubeadm now errors out if an unsupported version of a known component group
is used.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
This change removes dependencies on the internal types of the kubelet and
kube-proxy component configs. Along with that defaulting and validation is
removed as well. kubeadm will display a warning, that it did not verify the
component config upon load.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Whenever kubeadm needs to fetch its configuration from the cluster, it gets
the component configuration of all supported components (currently only kubelet
and kube-proxy). However, kube-proxy is deemed an optional component and its
installation may be skipped (by skipping the addon/kube-proxy phase on init).
When kube-proxy's installation is skipped, its config map is not created and
all kubeadm operations, that fetch the config from the cluster, are bound to
fail with "not found" or "forbidden" (because of missing RBAC rules) errors.
To fix this issue, we have to ignore the 403 and 404 errors, returned on an
attempt to fetch kube-proxy's component config from the cluster.
The `GetFromKubeProxyConfigMap` function now supports returning nil for both
error and object to indicate just such a case.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
progagates the kubeadm FG to the individual k8scomponents
on the control-plane node.
* Note: Users who want to join worker nodes to the cluster
will have to specify the dual-stack FG to kubelet using the
nodeRegistration.kubeletExtraArgs option as part of their
join config. Alternatively, they can use KUBELET_EXTRA_ARGS.
kubeadm FG: kubernetes/kubeadm#1612
During the control plane joins, sometimes the control plane returns an
expected error when trying to download the `kubeadm-config` ConfigMap.
This is a workaround for this issue until the root cause is completely
identified and fixed.
Ideally, this commit should be reverted in the near future.
Automatic merge from submit-queue (batch tested with PRs 63011, 68089, 67944, 68132). If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.
Kubeadm upload and fetch of kubeam config v1alpha3
**What this PR does / why we need it**:
This PR implements upload and fetch of kubeam config v1alpha3 from cluster.
More in detail:
In upload, `kubeadm-config` gets
- `ClusterConfiguration` (without components config which are already stored in separated ConfigMaps)
- `ClusterStatus`(initialised or updated with the API endpoint of the current node)
During fetch `InitConfiguration` is composed with:
- `ClusterConfiguration` from `kubeadm-config`
- The `APIEndpoint` of the current node from `ClusterStatus` in `kubeadm-config`
- Component configs from corresponding ConfigMaps
**Which issue(s) this PR fixes** :
refs https://github.com/kubernetes/kubeadm/issues/911, refs https://github.com/kubernetes/kubeadm/issues/963
**Special notes for your reviewer**:
In order to implement this it was necessary to extend current component config management with a new GetFromConfigMap operation. This is implemented in a separated commit "
implement component configs GetFromConfigMap".
The real change build on this (commi "upload and fetch kubeadm v1alpha3")
**Release note**:
```release-note
NONE
```
/cc @kubernetes/sig-cluster-lifecycle-pr-reviews
/sig cluster-lifecycle
/area kubeadm
/kind enhancement
/assign @luxas
/assign @timothysc
/cc @chuckha @rosti @neolit123 @liztio
