From 200f464925dcebd8e22b078d50c460fd28e3a115 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=8D=92=E9=87=8E=E7=84=A1=E7=87=88?= <ttys3@outlook.com>
Date: Mon, 13 Apr 2020 20:15:08 +0800
Subject: [PATCH] smtp buildMessage(): flush quotedprintable writer buff
 explicitly

---
 backend/app/notify/email.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/backend/app/notify/email.go b/backend/app/notify/email.go
index 3edc36dd..f9800947 100644
--- a/backend/app/notify/email.go
+++ b/backend/app/notify/email.go
@@ -371,7 +371,10 @@ func (e *Email) buildMessage(subject, body, to, contentType, unsubscribeLink str
 	if _, err := qp.Write([]byte(body)); err != nil {
 		return "", err
 	}
-	defer qp.Close()
+	// flush now, must NOT use defer, for small body, defer may cause buff.String() got empty body
+	if err := qp.Close(); err != nil {
+		return "", fmt.Errorf("quotedprintable Write failed: %w", err)
+	}
 	m := buff.String()
 	message += "\n" + m
 	return message, nil