feat: support optional SMTP auth

dannykopping · dannykopping · commit da550f4bcaca · 2024-09-03T10:00:29.000+02:00
Signed-off-by: Danny Kopping &lt;danny@coder.com&gt;
diff --git a/coderd/notifications/dispatch/smtp.go b/coderd/notifications/dispatch/smtp.go
@@ -53,7 +53,8 @@ type SMTPHandler struct {
 	cfg codersdk.NotificationsEmailConfig
 	log slog.Logger
 
-	loginWarnOnce sync.Once
+	noAuthWarnOnce sync.Once
+	loginWarnOnce  sync.Once
 
 	helpers template.FuncMap
 }
@@ -431,6 +432,15 @@ func (s *SMTPHandler) loadCertificate() (*tls.Certificate, error) {
 func (s *SMTPHandler) auth(ctx context.Context, mechs string) (sasl.Client, error) {
 	username := s.cfg.Auth.Username.String()
 
+	// All auth mechanisms require username, so if one is not defined then don't return an auth client.
+	if username == "" {
+		s.noAuthWarnOnce.Do(func() {
+			s.log.Warn(ctx, "skipping auth; no username configured", slog.F("support_mechanisms", mechs))
+		})
+		// nolint:nilnil // This is a valid response.
+		return nil, nil
+	}
+
 	var errs error
 	list := strings.Split(mechs, " ")
 	for _, mech := range list {
diff --git a/coderd/notifications/dispatch/smtp_test.go b/coderd/notifications/dispatch/smtp_test.go
@@ -203,7 +203,6 @@ func TestSMTP(t *testing.T) {
 			retryable:        false,
 		},
 		{
-			// No auth, no problem!
 			name:      "No auth mechanisms supported, none configured",
 			authMechs: []string{},
 			cfg: codersdk.NotificationsEmailConfig{
@@ -213,6 +212,16 @@ func TestSMTP(t *testing.T) {
 			toAddrs:          []string{to},
 			expectedAuthMeth: "",
 		},
+		{
+			name:      "Auth mechanisms supported optionally, none configured",
+			authMechs: []string{sasl.Login, sasl.Plain},
+			cfg: codersdk.NotificationsEmailConfig{
+				Hello: hello,
+				From:  from,
+			},
+			toAddrs:          []string{to},
+			expectedAuthMeth: "",
+		},
 		/**
 		 * TLS connections
 		 */
