Add support for -get in yggdrasilconf

contrib/config/yggdrasilconf.go

@@ -12,6 +12,8 @@ import (
 	"flag"
 	"fmt"
 	"io/ioutil"
+	"os"
+	"reflect"
 	"strconv"
 
 	"github.com/hjson/hjson-go"
@@ -25,6 +27,7 @@ type nodeConfig = config.NodeConfig
 func main() {
 	useconffile := flag.String("useconffile", "/etc/yggdrasil.conf", "update config at specified file path")
 	usejson := flag.Bool("json", false, "write out new config as JSON instead of HJSON")
+	get := flag.Bool("get", false, "get value instead of setting it")
 	flag.Parse()
 	cfg := nodeConfig{}
 	var config []byte
@@ -51,6 +54,35 @@ func main() {
 		panic(err)
 	}
 	json.Unmarshal(confJSON, &cfg)
+	if *get {
+		item := reflect.ValueOf(cfg)
+		for _, arg := range flag.Args() {
+			if item.Kind() == reflect.Map {
+				for _, key := range item.MapKeys() {
+					if key.String() == arg {
+						item = item.MapIndex(key)
+					}
+				}
+			} else {
+				item = item.FieldByName(arg)
+			}
+			if !item.IsValid() {
+				os.Exit(1)
+				return
+			}
+		}
+		var bs []byte
+		if *usejson {
+			bs, err = json.Marshal(item.Interface())
+		} else {
+			bs, err = hjson.Marshal(item.Interface())
+		}
+		if err != nil {
+			panic(err)
+		}
+		fmt.Println(string(bs))
+		os.Exit(0)
+	} else {
 		switch flag.Arg(0) {
 		case "setMTU":
 			cfg.IfMTU, err = strconv.Atoi(flag.Arg(1))
@@ -91,6 +123,7 @@ func main() {
 		case "setNodeInfoName":
 			cfg.NodeInfo["name"] = flag.Arg(1)
 		}
+	}
 	var bs []byte
 	if *usejson {
 		bs, err = json.Marshal(cfg)