- Changes the following KubeletConfiguration fields from `string` to
`map[string]string`:
- `EvictionHard`
- `EvictionSoft`
- `EvictionSoftGracePeriod`
- `EvictionMinimumReclaim`
- Adds flag parsing shims to maintain Kubelet's public flags API, while
enabling structured input in the file API.
- Also removes `kubeletconfig.ConfigurationMap`, which was an ad-hoc flag
parsing shim living in the kubeletconfig API group, and replaces it
with the `MapStringString` shim introduced in this PR. Flag parsing
shims belong in a common place, not in the kubeletconfig API.
I manually audited these to ensure that this wouldn't cause errors
parsing the command line for syntax that would have previously been
error free (`kubeletconfig.ConfigurationMap` was unique in that it
allowed keys to be provided on the CLI without values. I believe this was
done in `flags.ConfigurationMap` to facilitate the `--node-labels` flag,
which rightfully accepts value-free keys, and that this shim was then
just copied to `kubeletconfig`). Fortunately, the affected fields
(`ExperimentalQOSReserved`, `SystemReserved`, and `KubeReserved`) expect
non-empty strings in the values of the map, and as a result passing the
empty string is already an error. Thus requiring keys shouldn't break
anyone's scripts.
- Updates code and tests accordingly.
Regarding eviction operators, directionality is already implicit in the
signal type (for a given signal, the decision to evict will be made when
crossing the threshold from either above or below, never both). There is
no need to expose an operator, such as `<`, in the API. By changing
`EvictionHard` and `EvictionSoft` to `map[string]string`, this PR
simplifies the experience of working with these fields via the
`KubeletConfiguration` type. Again, flags stay the same.
Other things:
- There is another flag parsing shim, `flags.ConfigurationMap`, from the
shared flag utility. The `NodeLabels` field still uses
`flags.ConfigurationMap`. This PR moves the allocation of the
`map[string]string` for the `NodeLabels` field from
`AddKubeletConfigFlags` to the defaulter for the external
`KubeletConfiguration` type. Flags are layered on top of an internal
object that has undergone conversion from a defaulted external object,
which means that previously the mere registration of flags would have
overwritten any previously-defined defaults for `NodeLabels` (fortunately
there were none).
This refactor removes the legacy KubeletConfig object and adds a new
KubeletDeps object, which contains injected runtime objects and
separates them from static config. It also reduces NewMainKubelet to two
arguments: a KubeletConfiguration and a KubeletDeps.
Some mesos and kubemark code was affected by this change, and has been
modified accordingly.
And a few final notes:
KubeletDeps:
KubeletDeps will be a temporary bin for things we might consider
"injected dependencies", until we have a better dependency injection
story for the Kubelet. We will have to discuss this eventually.
RunOnce:
We will likely not pull new KubeletConfiguration from the API server
when in runonce mode, so it doesn't make sense to make this something
that can be configured centrally. We will leave it as a flag-only option
for now. Additionally, it is increasingly looking like nobody actually uses the
Kubelet's runonce mode anymore, so it may be a candidate for deprecation
and removal.
This patch adds the --exit-on-lock-contention flag, which must be used
in conjunction with the --lock-file flag. When provided, it causes the
kubelet to wait for inotify events for that lock file. When an 'open'
event is received, the kubelet will exit.
Covered values:
- negative quantity value: error expected
- invalid quantity unit: error expected
- valid quantity: error not expected
Running go test with -v, returned error are logged as well for more information:
=== RUN TestValueOfAllocatableResources
--- PASS: TestValueOfAllocatableResources (0.00s)
server_test.go:47: negative quantity value: resource quantity for \"memory\" cannot be negative: -150G
server_test.go:47: invalid quantity unit: unable to parse quantity's suffix
PASS
ok k8s.io/kubernetes/cmd/kubelet/app 0.020s