There are a couple of problems with regards to the `omitempty` in v1beta1:
- It is not applied to certain fields. This makes emitting YAML configuration
files in v1beta1 config format verbose by both kubeadm and third party Go
lang tools. Certain fields, that were never given an explicit value would
show up in the marshalled YAML document. This can cause confusion and even
misconfiguration.
- It can be used in inappropriate places. In this case it's used for fields,
that need to be always serialized. The only one such field at the moment is
`NodeRegistrationOptions.Taints`. If the `Taints` field is nil, then it's
defaulted to a slice containing a single control plane node taint. If it's
an empty slice, no taints are applied, thus, the cluster behaves differently.
With that in mind, a Go program, that uses v1beta1 with `omitempty` on the
`Taints` field has no way to specify an explicit empty slice of taints, as
this would get lost after marshalling to YAML.
To fix these issues the following is done in this change:
- A whole bunch of additional omitemptys are placed at many fields in v1beta2.
- `omitempty` is removed from `NodeRegistrationOptions.Taints`
- A test, that verifies the ability to specify empty slice value for `Taints`
is included.
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>
In the past the discovery configuration expected, that we can support multiple
API server endpoints. In practice, we always end up with a single API server
endpoint, because, even in HA setups, we use a load balancer scheme for API
servers.
Therefore, to reduce complexity and improve readability of the config, the
multiple API server endpoints support is removed from the bootstrap token
discovery join method and configuration.
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
This change splits out discovery fields from JoinConfiguration by performing
the following changes:
- Introduce a BootstrapTokenDiscovery structure, that houses configuration
options needed for bootstrap token based discovery.
- Introduce a FileDiscovery structure, that houses configuration options
(currently only a single option) needed for KubeConfig based discovery.
- Introduce a Discovery structure, that houses common options (such as
discovery timeout and TLS bootstrap token) as well as pointer to an instance
of either BootstrapTokenDiscovery or FileDiscovery structures.
- Replace the old discovery related JoinConfiguration members with a single
Discovery member.
This change is required in order to cleanup the code of unnecessary logic and
make the serialized JoinConfiguration more structured (and therefore, more
intuitive).
Signed-off-by: Rostislav M. Georgiev <rostislavg@vmware.com>
