Function PluginRunCommand

cli-plugins/manager/manager.go:177–227

PluginRunCommand returns an [os/exec.Cmd] which when [os/exec.Cmd.Run] will execute the named plugin. The rootcmd argument is referenced to determine the set of builtin commands in order to detect conflicts. The error returned satisfies the [errdefs.IsNotFound] predicate if no plugin was found or if

(dockerCli config.Provider, name string, rootcmd *cobra.Command)

// The rootcmd argument is referenced to determine the set of builtin commands in order to detect conflicts.
// The error returned satisfies the [errdefs.IsNotFound] predicate if no plugin was found or if the first candidate plugin was invalid somehow.
func PluginRunCommand(dockerCli config.Provider, name string, rootcmd *cobra.Command) (*exec.Cmd, error) {
	// This uses the full original args, not the args which may
	// have been provided by cobra to our caller. This is because
	// they lack e.g. global options which we must propagate here.
	args := os.Args[1:]
	if !isValidPluginName(name) {
		// We treat this as "not found" so that callers will
		// fallback to their "invalid" command path.
		return nil, errPluginNotFound(name)
	}
	exename := addExeSuffix(metadata.NamePrefix + name)
	pluginDirs := getPluginDirs(dockerCli.ConfigFile())

	for _, d := range pluginDirs {
		path := filepath.Join(d, exename)

		// We stat here rather than letting the exec tell us
		// ENOENT because the latter does not distinguish a
		// file not existing from its dynamic loader or one of
		// its libraries not existing.
		if _, err := os.Stat(path); os.IsNotExist(err) {
			continue
		}

		c := &candidate{path: path}
		plugin, err := newPlugin(c, rootcmd.Commands())
		if err != nil {
			return nil, err
		}
		if plugin.Err != nil {
			// TODO: why are we not returning plugin.Err?
			return nil, errPluginNotFound(name)
		}
		cmd := exec.Command(plugin.Path, args...) // #nosec G204 -- ignore "Subprocess launched with a potential tainted input or cmd arguments"

		// Using dockerCli.{In,Out,Err}() here results in a hang until something is input.
		// See: - https://github.com/golang/go/issues/10338
		//      - https://github.com/golang/go/commit/d000e8742a173aa0659584aa01b7ba2834ba28ab
		// os.Stdin is a *os.File which avoids this behaviour. We don't need the functionality
		// of the wrappers here anyway.
		cmd.Stdin = os.Stdin
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr

		cmd.Env = append(cmd.Environ(), metadata.ReexecEnvvar+"="+os.Args[0])
		cmd.Env = appendPluginResourceAttributesEnvvar(cmd.Env, rootcmd, plugin)

		return cmd, nil
	}
	return nil, errPluginNotFound(name)
}

// IsPluginCommand checks if the given cmd is a plugin-stub.
func IsPluginCommand(cmd *cobra.Command) bool {