From 5ab23653440b93ec06b598ecb41e328b4c0131b1 Mon Sep 17 00:00:00 2001
From: Shinichi Ishimura <sishimura@seqsense.com>
Date: Tue, 23 Jul 2019 15:58:30 +0900
Subject: [PATCH] Add a nil check for the json conversion

---
 main.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/main.go b/main.go
index 687faa3..e22dc35 100644
--- a/main.go
+++ b/main.go
@@ -10,6 +10,7 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"reflect"
 	"text/template"
 	"time"
 
@@ -254,6 +255,9 @@ func newConfig() (*config, error) {
 
 	funcs := map[string]interface{}{
 		"json": func(in interface{}) (string, error) {
+			if in == nil || reflect.ValueOf(in).IsNil() {
+				return "", nil
+			}
 			b, err := json.Marshal(in)
 			if err != nil {
 				return "", err