super.setUp();
        notificationHelper = new NotificationHelper();
    }

    public void test_sendToSlack_withBlankWebhookUrls() {
        // Setup mock configuration with blank webhook URLs
        ComponentUtil.setFessConfig(new MockFessConfig() {
            @Override
            public String getSlackWebhookUrls() {
                return "";
            }
        });

    /** Property key for Slack webhook URLs configuration. */
    public static final String SLACK_WEBHOOK_URLS_PROPERTY = "slack.webhook.urls";

    /** Property key for Google Chat webhook URLs configuration. */
    public static final String GOOGLE_CHAT_WEBHOOK_URLS_PROPERTY = "google.chat.webhook.urls";

    /** Property key for browser locale usage in search configuration. */