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>
Currently kubeadm supports a couple of configuration versions - v1alpha3 and
v1beta1. The former is deprecated, but still supported.
To discourage users from using it and to speedup conversion to newer versions,
we disable the loading of deprecated configurations by all kubeadm
sub-commands, but "kubeadm config migrate".
v1alpha3 is still present and supported at source level, but cannot be used
directly with kubeadm and some of its internal APIs.
The added benefit to this is, that users won't need to lookup for an old
kubeadm binary after upgrade, just because they were stuck with a deprecated
config version for too long.
To achieve this, the following was done:
- ValidateSupportedVersion now has an allowDeprecated boolean parameter, that
controls if the function should return an error upon detecting deprecated
config version. Currently the only deprecated version is v1alpha3.
- ValidateSupportedVersion is made package private, because it's not used
outside of the package anyway.
- BytesToInitConfiguration and LoadJoinConfigurationFromFile are modified to
disallow loading of deprecated kubeadm config versions. An error message,
that points users to kubeadm config migrate is returned.
- MigrateOldConfig is still allowed to load deprecated kubeadm config versions.
- A bunch of tests were fixed to not expect success if v1alpha3 config is
supplied.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
MigrateOldConfigFromFile is a function, whose purpose is to migrate one config
into another. It is working OK for now, but it has some issues:
- It is incredibly inefficient. It can reload and re-parse a single config file
for up to 3 times.
- Because of the reloads, it has to take a file containing the configuration
(not a byte slice as most of the rest config functions). However, it returns
the migrated config in a byte slice (rather asymmetric from the input
method).
- Due to the above points it's difficult to implement a proper interface for
deprecated kubeadm config versions.
To fix the issues of MigrateOldConfigFromFile, the following is done:
- Re-implement the function by removing the calls to file loading package
public APIs and replacing them with newly extracted package private APIs that
do the job with pre-provided input data in the form of
map[GroupVersionKind][]byte.
- Take a byte slice of the input configuration as an argument. This makes the
function input symmetric to its output. Also, it's now renamed to
MigrateOldConfig to represent the change from config file path as an input
to byte slice.
- As a bonus (actually forgotten from a previous change) BytesToInternalConfig
is renamed to the more descriptive BytesToInitConfiguration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
Currently JoinConfigFileAndDefaultsToInternalConfig is doing a couple of
different things depending on its parameters. It:
- loads a versioned JoinConfiguration from an YAML file.
- returns defaulted JoinConfiguration allowing for some overrides.
In order to make code more manageable, the following steps are taken:
- Introduce LoadJoinConfigurationFromFile, which loads a versioned
JoinConfiguration from an YAML file, defaults it (both dynamically and
statically), converts it to internal JoinConfiguration and validates it.
- Introduce DefaultedJoinConfiguration, which returns defaulted (both
dynamically and statically) and verified internal JoinConfiguration.
The possibility of overwriting defaults via versioned JoinConfiguration is
retained.
- Re-implement JoinConfigFileAndDefaultsToInternalConfig to use
LoadJoinConfigurationFromFile and DefaultedJoinConfiguration.
- Replace some calls to JoinConfigFileAndDefaultsToInternalConfig with calls to
either LoadJoinConfigurationFromFile or DefaultedJoinConfiguration where
appropriate.
- Rename JoinConfigFileAndDefaultsToInternalConfig to the more appropriate name
LoadOrDefaultJoinConfiguration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
DetectUnsupportedVersion is somewhat uncomfortable, complex and inefficient
function to use. It takes an entire YAML document as bytes, splits it up to
byte slices of the different YAML sub-documents and group-version-kinds and
searches through those to detect an unsupported kubeadm config. If such config
is detected, the function returns an error, if it is not (i.e. the normal
function operation) everything done so far is discarded.
This could have been acceptable, if not the fact, that in all cases that this
function is called, the YAML document bytes are split up and an iteration on
GVK map is performed yet again. Hence, we don't need DetectUnsupportedVersion
in its current form as it's inefficient, complex and takes only YAML document
bytes.
This change replaces DetectUnsupportedVersion with ValidateSupportedVersion,
which takes a GroupVersion argument and checks if it is on the list of
unsupported config versions. In that case an error is returned.
ValidateSupportedVersion relies on the caller to read and split the YAML
document and then iterate on its GVK map checking if the particular
GroupVersion is supported or not.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
When golint is run against kubeadm it reports severel warnings like
redundant if ...; err != nil check, just return error instead.
Fix the warnings by just returning error.
- Move from the old github.com/golang/glog to k8s.io/klog
- klog as explicit InitFlags() so we add them as necessary
- we update the other repositories that we vendor that made a similar
change from glog to klog
* github.com/kubernetes/repo-infra
* k8s.io/gengo/
* k8s.io/kube-openapi/
* github.com/google/cadvisor
- Entirely remove all references to glog
- Fix some tests by explicit InitFlags in their init() methods
Change-Id: I92db545ff36fcec83afe98f550c9e630098b3135
