From 5684bd1da5e58fd00ee441076a24588444f3a469 Mon Sep 17 00:00:00 2001
From: phil <zgrubby@gmail.com>
Date: Thu, 7 May 2020 15:46:50 +0800
Subject: [PATCH] create file atomic

---
 cache.go | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/cache.go b/cache.go
index ac52a71..004be1f 100644
--- a/cache.go
+++ b/cache.go
@@ -49,13 +49,22 @@ func (n *namespaceCache) dump(name string) error {
 		dumps[namespace] = cache.dump()
 	}
 
-	f, err := os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0755)
+	tmp := name + "tmp"
+	f, err := os.OpenFile(tmp, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0755)
 	if err != nil {
 		return err
 	}
-	defer f.Close()
 
-	return gob.NewEncoder(f).Encode(&dumps)
+	if err := gob.NewEncoder(f).Encode(&dumps); err != nil {
+		_ = f.Close()
+		return err
+	}
+
+	if err := f.Close(); err != nil {
+		return err
+	}
+
+	return os.Rename(tmp, name)
 }
 
 func (n *namespaceCache) load(name string) error {