Before this patch, output for invalid top-level and sub-commands differed.
For top-level commands, the CLI would print an error-message and a suggestion
to use `--help`. For missing *subcommands*, we would hit a different code-path,
and different output, which includes full "usage" / "help" output.
While it is a common convention to show usage output, and may have been
a nice gesture when docker was still young and only had a few commands
and options ("you did something wrong; here's an overview of what you
can use"), that's no longer the case, and many commands have a _very_
long output.
The result of this is that the error message, which is the relevant
information in this case - "You mis-typed something" - is lost in the
output, and hard to find (sometimes even requiring scrolling back).
The output is also confusing, because it _looks_ like something ran
successfully (most of the output is not about the error!).
Even further; the suggested resolution (try `--help` to see the correct
options) is rather redundant, because running teh command with `--help`
produces _exactly_ the same output as was just showh, baring the error
message. As a fun fact, due to the usage output being printed, the
output even contains not one, but _two_ "call to actions";
- `See 'docker volume --help'.` (under the erro message)
- `Run 'docker volume COMMAND --help' for more information on a command.`
(under the usage output)
In short; the output is too verbose, confusing, and doesn't provide
a good UX. Let's reduce the output produced so that the focus is on the
important information.
This patch:
- Changes the usage to the short-usage.
- Changes the error-message to mention the _full_ command instead of only
the command after `docker` (so `docker no-such-command` instead of
`no-such-command`).
- Prefixes the error message with the binary / root-command name
(usually `docker:`); this is something we can still decide on, but
it's a pattern we already use in some places. The motivation for this
is that `docker` commands can often produce output that's a combination
of output from the CLI itself, output from the daemon, and even output
from the container. The `docker:` prefix helps to distinguish where
the message originated from (the `docker` CLI in this case).
- Adds an empty line between the error-message and the "call to action"
(`Run 'docker volume --help'...` in the example below). This helps
separating the error message ("unkown flag") from the call-to-action.
Before this patch:
Unknown top-level command:
docker nosuchcommand foo
docker: 'nosuchcommand' is not a docker command.
See 'docker --help'
Unknown sub-command:
docker volume nosuchcommand foo
Usage: docker volume COMMAND
Manage volumes
Commands:
create Create a volume
inspect Display detailed information on one or more volumes
ls List volumes
prune Remove unused local volumes
rm Remove one or more volumes
update Update a volume (cluster volumes only)
Run 'docker volume COMMAND --help' for more information on a command.
After this patch:
Unknown top-level command:
docker nosuchcommand foo
docker: unknown command: docker nosuchcommand
Run 'docker --help' for more information
Unknown sub-command:
docker volume nosuchcommand foo
docker: unknown command: 'docker volume nosuchcommand'
Usage: docker volume COMMAND
Run 'docker volume --help' for more information
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
When a plugin is invoked, the docker cli will now set
`OTEL_RESOURCE_ATTRIBUTES` to pass OTEL resource attribute names to the
plugin as additional resource attributes. At the moment, the only
resource attribute passed is `cobra.command_path`.
All resource attributes passed by the CLI are prepended with the
namespace `docker.cli` to avoid clashing with existing ones the plugin
uses or ones defined by the user.
For aliased commands like the various builder commands, the command path
is overwritten to match with the original name (such as `docker
builder`) instead of the forwarded name (such as `docker buildx build`).
Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
We are currently loading plugin command stubs for every
invocation which still has a significant performance hit.
With this change we are doing this operation only if cobra
completion arg request is found.
- 20.10.23: `docker --version` takes ~15ms
- 23.0.1: `docker --version` takes ~93ms
With this change `docker --version` takes ~9ms
Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>
- The placement of the vendor is now in the end of the line.
- A '*' is now added as suffix of plugins' top level commands.
Signed-off-by: Ulysses Souza <ulysses.souza@docker.com>
They were listed twice in `docker --help` (but not `docker help`), since the
stubs were added in both `tryRunPluginHelp` and the `setHelpFunc` closure.
Calling `AddPluginStubCommands` earlier in `setHelpFunc` before the call to
`tryRunPluginHelp` is sufficient. Also it is no longer necessary to add just
valid plugins (`tryRunPluginHelp` handles invalid plugins correctly) so remove
that logic (which was in any case broken for e.g. `docker --help`).
Update the e2e test to check for duplicate entries and also to test `docker
--help` which was previously missed.
Signed-off-by: Ian Campbell <ijc@docker.com>
To do this we add a stub `cobra.Command` for each installed plugin (only when
invoking `help`, not for normal running).
This requires a function to list all available plugins so that is added here.
Signed-off-by: Ian Campbell <ijc@docker.com>
Sebastiaan van Stijn
Tonis Tiigi
Jonathan A. Sternberg
Kevin Alvarez
Nicolas De Loof
Ulysses Souza
Ian Campbell