commands: driver management command stubs

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

commands/ls.go

@@ -0,0 +1,48 @@
+package commands
+
+import (
+	"fmt"
+
+	"github.com/docker/cli/cli"
+	"github.com/docker/cli/cli/command"
+	"github.com/spf13/cobra"
+)
+
+type lsOptions struct {
+}
+
+func runLs(dockerCli command.Cli, in lsOptions) error {
+	fmt.Printf("current config file: %+v\n", dockerCli.ConfigFile().Filename)
+	fmt.Printf("current context: %+v\n", dockerCli.CurrentContext())
+
+	list, err := dockerCli.ContextStore().ListContexts()
+	if err != nil {
+		return err
+	}
+	for i, l := range list {
+		fmt.Printf("context%d: %+v\n", i, l)
+	}
+
+	return nil
+}
+
+func lsCmd(dockerCli command.Cli) *cobra.Command {
+	var options lsOptions
+
+	cmd := &cobra.Command{
+		Use:   "ls",
+		Short: "List builder instances",
+		Args:  cli.ExactArgs(0),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runLs(dockerCli, options)
+		},
+	}
+
+	flags := cmd.Flags()
+
+	// flags.StringArrayVarP(&options.outputs, "output", "o", []string{}, "Output destination (format: type=local,dest=path)")
+
+	_ = flags
+
+	return cmd
+}