Refine commandline help messages

[jiangliu]

Refine commandline help messages.

Signed-off-by: Jiang Liu gerry@linux.alibaba.com

root@91435c1ca697:/nydus# bin/containerd-nydus-grpc -h
NAME:
   containerd-nydus-grpc - Nydus remote snapshotter for containerd

USAGE:
   containerd-nydus-grpc [global options] command [command options] [arguments...]

VERSION:
   da88d96

COMMANDS:
   help, h  Shows a list of commands or help for one command

GLOBAL OPTIONS:
   --address PATH                               set PATH for gRPC socket (default: "/run/containerd-nydus/containerd-nydus-grpc.sock")
   --cache-dir DIRECTORY, -C DIRECTORY          set DIRECTORY to store/cache downloaded image data
   --cleanup-on-close                           whether to clean up on exit (default: false)
   --config-path FILE, -c FILE, --config FILE   path to the configuration FILE
   --convert-vpc-registry                       whether to automatically convert the image to vpc registry to accelerate image pulling (default: false)
   --daemon-mode MODE, -M MODE                  set daemon working MODE, one of "multiple", "shared" or "none" (default: "multiple")
   --disable-cache-manager                      whether to disable blob cache manager (default: false)
   --enable-metrics                             whether to collect metrics (default: false)
   --enable-nydus-overlayfs                     whether to enable nydus-overlayfs (default: false)
   --enable-stargz                              whether to enable support of estargz image (experimental) (default: false)
   --fs-driver DRIVER, --daemon-backend DRIVER  backend DRIVER to serve the filesystem, one of "fusedev", "fscache" (default: "fusedev")
   --gc-period INTERVAL                         blob cache garbage collection INTERVAL, duration string(for example, 1m, 2h) (default: "24h")
   --log-dir DIRECTORY, -L DIRECTORY            set DIRECTORY to store log files
   --log-level LEVEL, -l LEVEL                  set the logging LEVEL [trace, debug, info, warn, error, fatal, panic] (default: "info")
   --log-to-stdout                              log messages to standard out rather than files. (default: false)
   --metrics-file FILE                          path to the metrics output FILE
   --nydus-image PATH, --nydusimg-path PATH     set PATH to the nydus-image binary, default to lookup nydus-image in $PATH
   --nydusd PATH, --nydusd-path PATH            set PATH to the nydusd binary, default to lookup nydusd in $PATH
   --nydusd-thread-num value                    set worker thread number for nydusd, default to the number of CPUs (default: 0)
   --publickey-file FILE                        path to the publickey FILE for signature validation (default: "/signing/nydus-image-signing-public.key")
   --root DIRECTORY, -R DIRECTORY               set DIRECTORY to store snapshotter working state (default: "/var/lib/containerd-nydus-grpc")
   --shared-daemon                              Deprecated, equivalent to "--daemon-mode shared" (default: false)
   --sync-remove                                whether to clean up snapshots in synchronous mode, default to asynchronous mode (default: false)
   --validate-signature                         whether to validate integrity of image bootstrap (default: false)
   --help, -h                                   show help (default: false)
   --version, -v                                print the version (default: false)

[codecov-commenter]

Codecov Report

Merging #95 (da88d96) into main (542d7e7) will increase coverage by 0.18%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #95      +/-   ##
==========================================
+ Coverage   28.66%   28.85%   +0.18%     
==========================================
  Files          17       17              
  Lines        1528     1532       +4     
==========================================
+ Hits          438      442       +4     
  Misses       1026     1026              
  Partials       64       64              

Impacted Files	Coverage Δ
cmd/containerd-nydus-grpc/pkg/command/flags.go	78.19% <100.00%> (+0.47%)	⬆️

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[imeoer]

LGTM!