From 3093be222258db93270e3ff9a1b0c6d277519127 Mon Sep 17 00:00:00 2001
From: LanQin_ <lanqinnet@qq.com>
Date: Tue, 16 Jun 2026 15:10:28 +0800
Subject: [PATCH] =?UTF-8?q?fix(mail):=20=E5=8F=91=E9=80=81=E5=A4=B1?=
 =?UTF-8?q?=E8=B4=A5=E6=97=B6=E8=BF=94=E5=9B=9E=20SMTP=20=E9=94=99?=
 =?UTF-8?q?=E8=AF=AF?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- 发送邮件时若 `SMTP` 投递失败，直接返回 `502 Bad Gateway`。
- 新增测试覆盖投递失败场景，确认错误信息会透出。
---
 apps/api/internal/app/app_test.go      | 26 ++++++++++++++++++++++++++
 apps/api/internal/app/mail_handlers.go |  3 ++-
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/apps/api/internal/app/app_test.go b/apps/api/internal/app/app_test.go
index d8f5e56..41bc943 100644
--- a/apps/api/internal/app/app_test.go
+++ b/apps/api/internal/app/app_test.go
@@ -589,6 +589,32 @@ func TestCatchAllStoresUnregisteredMailForAdminOnly(t *testing.T) {
 	}
 }
 
+func TestMailSendReturnsSMTPFailure(t *testing.T) {
+	a := newTestApp(t)
+	a.cfg.SMTPHost = "127.0.0.1"
+	a.cfg.SMTPPort = "1"
+	ts := httptest.NewServer(a.Router())
+	defer ts.Close()
+	admin := &testClient{t: t, server: ts}
+
+	var login map[string]any
+	if code := admin.do("POST", "/api/auth/login", map[string]string{"email": "admin@lanqin.local", "password": "ChangeMe123!"}, &login); code != http.StatusOK {
+		t.Fatalf("login code=%d body=%v", code, login)
+	}
+	payload := map[string]any{
+		"to":      []string{"person@example.com"},
+		"subject": "smtp failure should surface",
+		"text":    "hello",
+	}
+	var errBody map[string]any
+	if code := admin.do("POST", "/api/mail/send", payload, &errBody); code != http.StatusBadGateway {
+		t.Fatalf("smtp failure code=%d body=%v", code, errBody)
+	}
+	if got, _ := errBody["error"].(string); !strings.Contains(got, "smtp delivery failed") {
+		t.Fatalf("error=%q", got)
+	}
+}
+
 func TestAdminSMTPTestEndpoint(t *testing.T) {
 	a := newTestApp(t)
 	host, port, received := startFakeSMTP(t)
diff --git a/apps/api/internal/app/mail_handlers.go b/apps/api/internal/app/mail_handlers.go
index 31311ce..da13a9b 100644
--- a/apps/api/internal/app/mail_handlers.go
+++ b/apps/api/internal/app/mail_handlers.go
@@ -330,7 +330,8 @@ func (a *App) handleMailSend(w http.ResponseWriter, r *http.Request) {
 	}
 	if a.cfg.SMTPHost != "" {
 		if err := a.sendSMTP(mb.Address, allRecipients, mimeBytes); err != nil {
-			a.log.Warn("smtp delivery failed; keeping local sent copy", "error", err)
+			respondError(w, http.StatusBadGateway, "smtp delivery failed: "+err.Error())
+			return
 		}
 	}