What causes "Bark notification failed with invalid response!" in louislam/uptime-kuma?

Confirm the Bark endpoint URL is correct and the server is up.

louislam/uptime-kuma · error · Error

Bark notification failed with invalid response!

Error message

Bark notification failed with invalid response!

What it means

bark.js:78-86 (checkResult). A defensive guard: if the Axios response object has no `status` at all (null/undefined) the response is unusable, so the provider refuses to guess and throws 'invalid response'. Distinct from the status-out-of-range error.

Source

Thrown at server/notification-providers/bark.js:82

        // picked a sound, this should follow system's mute status when arrival
        if (notification.barkSound != null) {
            params += "&sound=" + notification.barkSound;
        } else {
            // default sound
            params += "&sound=" + "telegraph";
        }
        return params;
    }

    /**
     * Check if result is successful
     * @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("Bark notification failed with invalid response!");
        }
        if (result.status < 200 || result.status >= 300) {
            throw new Error("Bark notification failed with status code " + result.status);
        }
    }

    /**
     * Send the message
     * @param {BeanModel} notification Notification to send
     * @param {string} title Message title
     * @param {string} subtitle Message
     * @param {string} endpoint Endpoint to send request to
     * @returns {Promise<string>} Success message
     */
    async postNotification(notification, title, subtitle, endpoint) {
        let result;
        let config = this.getAxiosConfigWithProxy({});
        if (notification.apiVersion === "v1" || notification.apiVersion == null) {

View on GitHub (pinned to 6b5ea01557)

Solutions

Confirm the Bark endpoint URL is correct and the server is up.
Test the endpoint directly: `curl -i https://api.day.app/<key>/<title>/<body>`.
If self-hosting Bark, upgrade to a version that returns proper HTTP status codes.
Remove any Axios response interceptors that overwrite the status field.

Defensive patterns

Strategy: type-guard

Validate before calling

// Verify the response shape before calling checkResult
function isUsableResponse(r) { return r != null && typeof r.status === 'number'; }

Type guard

function hasBarkStatus(r) { return r != null && (typeof r.status === 'number' || r.status == null); }

Try / catch

try { provider.checkResult(result); }
catch (e) {
    if (/invalid response/.test(e.message)) log.error('Bark returned a response with no HTTP status — endpoint malformed');
}

Prevention

Self-hosted Bark servers should return proper HTTP status lines — keep them updated.
Avoid Axios interceptors that mutate the response shape.

When it happens

Trigger: Axios returned a response with status unset (rare — usually means a network layer swallowed the HTTP layer), the Bark server returned a non-HTTP/empty byte stream, or a proxy returned an opaque object lacking status.

Common situations: Custom Bark-compatible self-hosted server returning malformed responses; intermediary that strips the status field; Axios interceptor mutating the response object.

Related errors

AI-assisted analysis of louislam/uptime-kuma@6b5ea01557 (2026-08-12). Data as JSON: /api/errors/f79679777d484519. Report an issue: GitHub.