DockerCLI/cli
Sebastiaan van Stijn d738e7c489
docker info: skip API connection if possible
The docker info output contains both "local" and "remote" (daemon-side) information.
The API endpoint to collect daemon information (`/info`) is known to be "heavy",
and (depending on what information is needed) not needed.

This patch checks if the template (`--format`) used requires information from the
daemon, and if not, omits making an API request.

This will improve performance if (for example), the current "context" is requested
from `docker info` or if only plugin information is requested.

Before:

    time docker info --format '{{range  .ClientInfo.Plugins}}Plugin: {{.Name}}, {{end}}'
    Plugin: buildx, Plugin: compose, Plugin: scan,

    ________________________________________________________
    Executed in  301.91 millis    fish           external
       usr time  168.64 millis   82.00 micros  168.56 millis
       sys time  113.72 millis  811.00 micros  112.91 millis

    time docker info --format '{{json .ClientInfo.Plugins}}'

    time docker info --format '{{.ClientInfo.Context}}'
    default

    ________________________________________________________
    Executed in  334.38 millis    fish           external
       usr time  177.23 millis   93.00 micros  177.13 millis
       sys time  124.90 millis  927.00 micros  123.97 millis

    docker context use remote-ssh-daemon
    time docker info --format '{{.ClientInfo.Context}}'
    remote-ssh-daemon

    ________________________________________________________
    Executed in    1.22 secs   fish           external
       usr time  116.93 millis  110.00 micros  116.82 millis
       sys time  144.36 millis  887.00 micros  143.47 millis

And daemon logs:

    Jul 06 12:42:12 remote-ssh-daemon dockerd[14377]: time="2021-07-06T12:42:12.139529947Z" level=debug msg="Calling HEAD /_ping"
    Jul 06 12:42:12 remote-ssh-daemon dockerd[14377]: time="2021-07-06T12:42:12.140772052Z" level=debug msg="Calling HEAD /_ping"
    Jul 06 12:42:12 remote-ssh-daemon dockerd[14377]: time="2021-07-06T12:42:12.163832016Z" level=debug msg="Calling GET /v1.41/info"

After:

    time ./build/docker info --format '{{range  .ClientInfo.Plugins}}Plugin: {{.Name}}, {{end}}'
    Plugin: buildx, Plugin: compose, Plugin: scan,

    ________________________________________________________
    Executed in  139.84 millis    fish           external
       usr time   76.53 millis   62.00 micros   76.46 millis
       sys time   69.25 millis  723.00 micros   68.53 millis

    time ./build/docker info --format '{{.ClientInfo.Context}}'
    default

    ________________________________________________________
    Executed in  136.94 millis    fish           external
       usr time   74.61 millis   74.00 micros   74.54 millis
       sys time   65.77 millis  858.00 micros   64.91 millis

    docker context use remote-ssh-daemon
    time ./build/docker info --format '{{.ClientInfo.Context}}'
    remote-ssh-daemon

    ________________________________________________________
    Executed in    1.02 secs   fish           external
       usr time   74.25 millis   76.00 micros   74.17 millis
       sys time   65.09 millis  643.00 micros   64.44 millis

And daemon logs:

    Jul 06 12:42:55 remote-ssh-daemon dockerd[14377]: time="2021-07-06T12:42:55.313654687Z" level=debug msg="Calling HEAD /_ping"
    Jul 06 12:42:55 remote-ssh-daemon dockerd[14377]: time="2021-07-06T12:42:55.314811624Z" level=debug msg="Calling HEAD /_ping"

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2021-07-06 17:04:34 +02:00
..
command docker info: skip API connection if possible 2021-07-06 17:04:34 +02:00
compose Support ulimits in docker stack deploy 2020-09-10 14:59:02 +02:00
config cli/config/configfile: various test cleanups 2021-04-30 10:03:51 +02:00
connhelper Use designated test domains (RFC2606) in tests 2021-04-30 10:03:45 +02:00
context context: Ensure context name is valid on import 2021-02-02 13:51:15 +01:00
debug updated vendoring 2017-09-01 19:41:06 -04:00
flags bump gotest.tools v3.0.1 for compatibility with Go 1.14 2020-02-23 00:28:55 +01:00
manifest bump gotest.tools v3.0.1 for compatibility with Go 1.14 2020-02-23 00:28:55 +01:00
registry/client vendor: github.com/docker/docker 25917217cab38eab40c3db0010b915258f4a8491 2021-06-22 10:16:54 +02:00
streams update docker, replace github.com/docker/pkg/term, github.com/docker/pkg/mount 2020-04-22 17:16:13 +02:00
trust bump gotest.tools v3.0.1 for compatibility with Go 1.14 2020-02-23 00:28:55 +01:00
version Move versioning variables to a separate package. 2019-01-29 11:26:40 +00:00
winresources update windows resources generation 2021-04-06 00:20:59 -07:00
cobra.go Help link: remove color, add "bold" style, and white-space 2020-12-14 14:28:29 +01:00
cobra_test.go bump gotest.tools v3.0.1 for compatibility with Go 1.14 2020-02-23 00:28:55 +01:00
error.go Import docker/docker/cli 2017-04-17 17:40:59 -04:00
required.go Disable unparam linter: cli/required.go:102:16: `pluralize` - `word` always receives `"argument"` (unparam) 2019-10-31 19:22:22 +01:00
required_test.go Replace deprecated Cobra command.SetOutput() with command.SetOut() 2020-05-07 14:25:59 +02:00