cli: refactor to allow definition of subcommands next to their implementation

client/configcheck.go

@@ -1,8 +1,36 @@
 package client
 
-import "github.com/zrepl/zrepl/config"
+import (
+	"encoding/json"
+	"github.com/kr/pretty"
+	"github.com/spf13/pflag"
+	"github.com/zrepl/yaml-config"
+	"github.com/zrepl/zrepl/cli"
+	"os"
+)
 
-func RunConfigcheck(conf *config.Config, args []string) error {
-	// TODO: do the 'build' steps, e.g. build the jobs and see if that fails
-	return nil
+var configcheckArgs struct {
+	format string
 }
+
+var ConfigcheckCmd = &cli.Subcommand{
+	Use: "configcheck",
+	Short: "check if config can be parsed without errors",
+	SetupFlags: func(f *pflag.FlagSet) {
+		f.StringVar(&configcheckArgs.format, "format", "", "dump parsed config object [pretty|yaml|json]")
+	},
+	Run: func(subcommand *cli.Subcommand, args []string) error {
+		switch configcheckArgs.format {
+		case "pretty":
+			_, err := pretty.Println(subcommand.Config())
+			return err
+		case "json":
+			return json.NewEncoder(os.Stdout).Encode(subcommand.Config())
+		case "yaml":
+			return yaml.NewEncoder(os.Stdout).Encode(subcommand.Config())
+		default: // no output
+		}
+		return nil
+	},
+}
+