louislam/uptime-kuma · warning · Error

PagerTree notification failed with invalid response!

Error message

PagerTree notification failed with invalid response!

What it means

PagerTree's checkResult(result) guard fires when result.status == null — the response object exists but has no numeric status. Mirror of the PagerDuty pattern: a defensive check for an unexpected/empty response before the 2xx range test.

Source

Thrown at server/notification-providers/pagertree.js:47

            if (heartbeatJSON.status === DOWN) {
                const title = `Uptime Kuma Monitor "${monitorJSON.name}" is DOWN`;
                return this.postNotification(notification, title, monitorJSON, heartbeatJSON);
            }
        } catch (error) {
            this.throwGeneralAxiosError(error);
        }
    }

    /**
     * Check if result is successful, result code should be in range 2xx
     * @param {object} result Axios response object
     * @returns {void}
     * @throws {Error} The status code is not in range 2xx
     */
    checkResult(result) {
        if (result.status == null) {
            throw new Error("PagerTree notification failed with invalid response!");
        }
        if (result.status < 200 || result.status >= 300) {
            throw new Error("PagerTree notification failed with status code " + result.status);
        }
    }

    /**
     * Send the message
     * @param {BeanModel} notification Message title
     * @param {string} title Message title
     * @param {object} monitorJSON Monitor details (For Up/Down only)
     * @param {object} heartbeatJSON Heartbeat details (For Up/Down only)
     * @param {?string} eventAction Action event for PagerTree (create, resolve)
     * @returns {Promise<string>} Success state
     */
    async postNotification(notification, title, monitorJSON, heartbeatJSON, eventAction = "create") {
        if (eventAction == null) {
            return "No action required";

View on GitHub (pinned to 6b5ea01557)

Solutions

1. Log the raw result object to identify why status is null.
2. Fix/remove custom axios interceptors or adapters on this request path.
3. Ensure any proxy in front of PagerTree preserves the HTTP status line.
4. Set status explicitly in any mocked responses.

/** @param {unknown} r */
function hasHttpStatus(r) {
    return typeof r === "object" && r !== null &&
        typeof r.status === "number" && r.status >= 100 && r.status < 600;
}

if (!hasHttpStatus(result)) {
    throw new Error("PagerTree returned a malformed response (no HTTP status)");
}

When it happens

Trigger: A custom axios adapter/interceptor or an intermediary proxy returned a response object without a status field; mocked responses in tests omit status; the PagerTree response was malformed in transit.

Common situations: Misbehaving reverse proxy; axios response transformer that drops status; tests with incomplete mocks.

Related errors

• PagerDuty notification failed with invalid response!
• Your JSON body is invalid. ${e.message}
• Headers must be valid JSON: ${e.message}
• Accepted status codes must be valid JSON: ${e.message}
• PagerTree notification failed with status code ${result.stat

AI-assisted analysis of louislam/uptime-kuma@6b5ea01557 (2026-08-12). Data as JSON: /api/errors/40b31bd5577b54f6. Report an issue: GitHub.