feat: use gomail for shoutrrr SMTP

mail/mailer.go

@@ -13,6 +13,11 @@ type Mail struct {
 	message *gomail.Message
 }
 
+func (t *Mail) SetFrom(from string) *Mail {
+	t.message.SetHeader("From", from)
+	return t
+}
+
 func New(to, subject, body, contentType string) *Mail {
 	m := gomail.NewMessage()
 	m.SetHeader("From", FromAddress)

notification/shoutrrr.go

@@ -91,6 +91,25 @@ func Send(ctx *api.Context, connectionName, shoutrrrURL, title, message string,
 	var params *types.Params
 	if properties != nil {
 		params = (*types.Params)(&allProps)
+	} else {
+		params = &types.Params{}
+	}
+
+	// NOTE: Until shoutrrr fixes the "UseHTML" props, we'll use the mailer package
+	if service == "smtp" {
+		parsedURL, err := url.Parse(shoutrrrURL)
+		if err != nil {
+			return fmt.Errorf("failed to parse shoutrrr URL: %w", err)
+		}
+
+		query := parsedURL.Query()
+		var (
+			to   = utils.Coalesce(query.Get("ToAddresses"), (*params)["ToAddresses"])
+			from = utils.Coalesce(query.Get("FromAddress"), (*params)["FromAddress"])
+		)
+
+		m := mail.New(to, title, message, `text/html; charset="UTF-8"`).SetFrom(from)
+		return m.Send()
 	}
 
 	sendErrors := sender.Send(message, params)