Add util method for encoding

utils/encoding.go

@@ -0,0 +1,17 @@
+package utils
+
+import (
+	"encoding/base64"
+)
+
+func Base64DecodeString(s string) []byte {
+	b, err := base64.StdEncoding.DecodeString(s)
+	if err != nil {
+		panic(err)
+	}
+	return b
+}
+
+func BytesToBase64(b []byte) string {
+	return base64.StdEncoding.EncodeToString(b)
+}