Moving the registry into its own package will avoid dependency cycles in future
PRs.
Creating loggers through a factory instead of storing pre-created instances
will make it possible to create the loggers differently depending on
configuration parameters.
The factory can also be used to provide additional meta data before creating
instances.
The name concatenation and ownership check were originally considered small
enough to not warrant dedicated functions, but the intent of the code is more
readable with them.
enhance client-go DebugURLTiming roundtripper using golang httptrace
to provide timing statistics for:
- dns lookup
- tcp dialing
- tls handshake
- time to get a connection from the pool
- time to process a request
Upstream klog continues to support all of its flags, but in Kubernetes only
some will be supported going format (-v, -vmodule). With this change,
the kubelet flags now look like this:
$ go run ./cmd/kubelet --help | grep -e --log-dir -e '--v ' -e --vmodule -e --logging-format
--log-dir string If non-empty, write log files in this directory (DEPRECATED: will be removed in a future release, see https://github.com/kubernetes/enhancements/tree/master/keps/sig-instrumentation/2845-deprecate-klog-specific-flags-in-k8s-components)
--logging-format string Sets the log format. Permitted formats: "json", "text".
Non-default formats don't honor these flags: --add_dir_header, --alsologtostderr, --log_backtrace_at, --log_dir, --log_file, --log_file_max_size, --logtostderr, --one_output, --skip_headers, --skip_log_headers, --stderrthreshold, --vmodule, --log-flush-frequency, --add_dir_header, --alsologtostderr, --log_backtrace_at, --log_dir, --log_file, --log_file_max_size, --logtostderr, --one_output, --skip_headers, --skip_log_headers, --stderrthreshold, --vmodule.
-v, --v Level number for the log level verbosity
--vmodule moduleSpec comma-separated list of pattern=N settings for file-filtered logging
The recommendation from #sig-cli was to print usage, then the error. Extra care
is taken to only print the usage instruction when the error really was about
flag parsing.
Taking kube-scheduler as example:
$ _output/bin/kube-scheduler
I0929 09:42:42.289039 149029 serving.go:348] Generated self-signed cert in-memory
...
W0929 09:42:42.489255 149029 client_config.go:620] error creating inClusterConfig, falling back to default config: unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined
E0929 09:42:42.489366 149029 run.go:98] "command failed" err="invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable"
$ _output/bin/kube-scheduler --xxx
Usage:
kube-scheduler [flags]
...
--vmodule moduleSpec
comma-separated list of pattern=N settings for file-filtered logging
Error: unknown flag: --xxx
The kubectl behavior doesn't change:
$ _output/bin/kubectl get nodes
Unable to connect to the server: dial tcp: lookup xxxx: No address associated with hostname
$ _output/bin/kubectl --xxx
Error: unknown flag: --xxx
See 'kubectl --help' for usage.
All Kubernetes commands should show flags with hyphens in their help text even
when the flag originally was defined with underscore. Converting a command to
this style is not breaking its command line API because the old-style parameter
with underscore is accepted as alias.
The easiest solution to achieve this is to set normalization shortly before
running the command in the new central cli.Run or the few places where that
function isn't used yet.
There may be some texts which depends on normalization at flag definition time,
like the --logging-format usage warning. Those get generated assuming that
hyphens will be used.
