From d7221e15acd3a79c4e402e6dc249e2a648829d74 Mon Sep 17 00:00:00 2001
From: Mariano Cano <mariano@smallstep.com>
Date: Thu, 25 Jul 2019 18:41:46 -0700
Subject: [PATCH] Always marshal timeduration as a string

---
 authority/provisioner/timeduration.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/authority/provisioner/timeduration.go b/authority/provisioner/timeduration.go
index 33104df3..ca80ba10 100644
--- a/authority/provisioner/timeduration.go
+++ b/authority/provisioner/timeduration.go
@@ -75,7 +75,7 @@ func (t TimeDuration) MarshalJSON() ([]byte, error) {
 	switch {
 	case t.t.IsZero():
 		if t.d == 0 {
-			return []byte("null"), nil
+			return []byte(`""`), nil
 		}
 		return json.Marshal(t.d.String())
 	default: