kubernetes/cmd/kube-scheduler
Patrick Ohly 1957fb6508 command lines: harmonize command line parse error handling
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.
2021-09-30 13:46:49 +02:00
..
app command lines: harmonize command line parse error handling 2021-09-30 13:46:49 +02:00
OWNERS delete all duplicate empty blanks 2019-02-23 10:28:04 +08:00
scheduler.go command lines: always show flags with hyphens 2021-09-30 13:46:49 +02:00