- 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).
The syscall package is locked down and the comment in [1] advises to
switch code to use the corresponding package from golang.org/x/sys. Do
so and replace usage of package syscall with package
golang.org/x/sys/unix where applicable.
[1] https://github.com/golang/go/blob/master/src/syscall/syscall.go#L21-L24
This will also allow to get updates and fixes for syscall wrappers
without having to use a new go version.
Errno, Signal and SysProcAttr aren't changed as they haven't been
implemented in /x/sys/. Stat_t from syscall is used if standard library
packages (e.g. os) require it. syscall.SIGTERM is used for
cross-platform files.
Automatic merge from submit-queue
Moved qos to api.helpers.
**What this PR does / why we need it**:
The `GetPodQoS` is also used by other components, e.g. kube-scheduler and it's not bound to kubelet; moved it to api helpers so client-go.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #N/A
**Release note**:
```release-note-none
```