when running integration tests without an external etcd, the framework
spawns an etcd instance executing it in its own process and killing
it once the test stops.
Instead of killing it directly, allow etcd to exit gracefully or kill
it after 5 seconds.
This provides a mechanism for overriding the forced increase of the klog
verbosity to 4 when starting the apiserver and uses that for the scheduler_perf
benchmark. Other tests run as before.
A global variable was used because adding an explicit parameter to several
helper functions would have caused a lot of code churn (test ->
integration/util.StartApiserver ->
integration/framework.RunAnAPIServerUsingServer ->
integration/framework.startAPIServerOrDie).
The apiserver may be configured to generate the Service
kubernetes.default and its endpoints addresses.
This service is single-stack, hence, the endpoints and the ClusterIP
must have the same IP family.
It wasn't documented that InitLogs already uses the log flush frequency, so
some commands have called it before parsing (for example, kubectl in the
original code for logs.go). The flag never had an effect in such commands.
Fixing this turned into a major refactoring of how commands set up flags and
run their Cobra command:
- component-base/logs: implicitely registering flags during package init is an
anti-pattern that makes it impossible to use the package in commands which
want full control over their command line. Logging flags must be added
explicitly now, something that the new cli.Run does automatically.
- component-base/logs: AddFlags would have crashed in kubectl-convert if it
had been called because it relied on the global pflag.CommandLine. This
has been fixed and kubectl-convert now has the same --log-flush-frequency
flag as other commands.
- component-base/logs/testinit: an exception are tests where flag.CommandLine has
to be used. This new package can be imported to add flags to that
once per test program.
- Normalization of the klog command line flags was inconsistent. Some commands
unintentionally didn't normalize to the recommended format with hyphens. This
gets fixed for sample programs, but not for production programs because
it would be a breaking change.
This refactoring has the following user-visible effects:
- The validation error for `go run ./cmd/kube-apiserver --logging-format=json
--add-dir-header` now references `add-dir-header` instead of `add_dir_header`.
- `staging/src/k8s.io/cloud-provider/sample` uses flags with hyphen instead of
underscore.
- `--log-flush-frequency` is not listed anymore in the --logging-format flag's
`non-default formats don't honor these flags` usage text because it will also
work for non-default formats once it is needed.
- `cmd/kubelet`: the description of `--logging-format` uses hyphens instead of
underscores for the flags, which now matches what the command is using.
- `staging/src/k8s.io/component-base/logs/example/cmd`: added logging flags.
- `apiextensions-apiserver` no longer prints a useless stack trace for `main`
when command line parsing raises an error.
By parsing flags in the test's main function before starting etcd we bail out
early without ever starting etcd when the test was invoked with -help.
Otherwise etcd must be available, gets started and then hangs because
flag.Parse itself exits when called by testing.go. This bypasses the code in
EtcdMain which normally stops etcd.
This is part of the goal for scheduling to remove dependencies on internal
packages for the scheduling framework. It also provides these functions in an
external location for other components and projects to import.
