From 998c23c3e9ac67bf1c27e0aada44f8cc0c38c2e2 Mon Sep 17 00:00:00 2001
From: Wilson Wang <wangwscn@hotmail.com>
Date: Mon, 6 Feb 2017 08:05:01 -0800
Subject: [PATCH] add json omitempty on button Title field (#25)

Share Button only allows the Type field to be presented in the serialized data. Otherwise, you got facebook error:

"Facebook error : (#100) Param [elements][0][buttons][0][title] must be a non-empty UTF-8 encoded string"
---
 response.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/response.go b/response.go
index f4de95c..61e095d 100644
--- a/response.go
+++ b/response.go
@@ -347,7 +347,7 @@ type StructuredMessageElement struct {
 type StructuredMessageButton struct {
 	Type    string `json:"type"`
 	URL     string `json:"url,omitempty"`
-	Title   string `json:"title"`
+	Title   string `json:"title,omitempty"`
 	Payload string `json:"payload,omitempty"`
 }