louislam/uptime-kuma · warning · Error

Slug -Accept string only

Error message

Slug -Accept string only

What it means

Thrown by addStatusPage when slug's typeof is not 'string', after the empty-check passes. It hardens slug handling before toLowerCase()/checkSlug are applied, since trim() was called via slug?.trim() which would throw on non-string without optional chaining in some cases.

Source

Thrown at server/socket-handlers/status-page-socket-handler.js:450

        }
    });

    // Add a new status page
    socket.on("addStatusPage", async (title, slug, callback) => {
        try {
            checkLogin(socket);

            title = title?.trim();
            slug = slug?.trim();

            // Check empty
            if (!title || !slug) {
                throw new Error("Please input all fields");
            }

            // Make sure slug is string
            if (typeof slug !== "string") {
                throw new Error("Slug -Accept string only");
            }

            // lower case only
            slug = slug.toLowerCase();

            checkSlug(slug);

            let statusPage = R.dispense("status_page");
            statusPage.slug = slug;
            statusPage.title = title;
            statusPage.theme = "auto";
            statusPage.icon = "";
            statusPage.autoRefreshInterval = 300;
            await R.store(statusPage);

            callback({
                ok: true,
                msg: "successAdded",

View on GitHub (pinned to 6b5ea01557)

Solutions

1. Pass slug as a string from the client (String(slug) before emitting if needed).
2. Validate typeof slug === 'string' client-side.
3. Align the client API contract to always send slug as string.

Example fix

// before
socket.emit("addStatusPage", "Main", 123, cb);
// after
socket.emit("addStatusPage", "Main", "123", cb);

if (typeof slug !== "string") slug = String(slug);
socket.emit("addStatusPage", title, slug, cb);

function isStringSlug(slug) {
  return typeof slug === "string";
}

try { await emitAsync("addStatusPage", title, slug, cb); }
catch (e) { if (/Accept string only/.test(e.message)) retryWithStringSlug(); else throw e; }

When it happens

Trigger: Client emits addStatusPage with slug as a number, object, array, or boolean (e.g. slug: 123). title passes the empty check but slug fails typeof === 'string'.

Common situations: Client coercion bug (slug parsed as number from URL); JSON payload built dynamically with a numeric slug; type confusion between client and server contract.

Related errors

• Please input title
• Please input content
• slug is not found
• No slug?
• Only allowed PNG logo.

AI-assisted analysis of louislam/uptime-kuma@6b5ea01557 (2026-08-12). Data as JSON: /api/errors/754ec8fc5b20118c. Report an issue: GitHub.