vectordotdev/vector · error

HTTP status codes are valid u16 values

Error message

HTTP status codes are valid u16 values

What it means

During the Keep sink healthcheck, the response's http::StatusCode is converted back into the local StatusCode type via StatusCode::from_u16 and unwrapped with expect. Because res.status().as_u16() already produced a valid HTTP status code, the conversion cannot fail; the expect documents that invariant. Hitting this panic indicates a malformed internal HTTP layer rather than a server problem.

Solutions

1. Inspect any proxies/middlewares rewriting HTTP responses between Vector and Keep.
2. Update the HTTP client dependency (reqwest/hyper) to a version that guarantees valid status codes.
3. Confirm Keep returns standard HTTP status codes (200/202/400 are handled explicitly).

// keep proxies from rewriting status lines; on healthcheck failure, alert and retry
// systemd auto-restart keeps the pipeline alive
Restart=on-failure

When it happens

Trigger: Healthcheck receives a response whose status code, when re-parsed via StatusCode::from_u16, is invalid — only possible if the HTTP client returned a fabricated non-standard status code outside 100..=599.

Common situations: Buggy or patched HTTP client/proxy in front of Keep injecting invalid status lines; effectively unreachable on stock builds since hyper/reqwest already validate status codes.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• building HTTP request failed unexpectedly
• Building request never fails.
• a valid HTTP/1 URI is valid as an HTTP URI
• a validated HTTP endpoint is a valid `http 1` URI
• Could not convert HTTP status code to JSON

AI-assisted analysis of vectordotdev/vector@bdb87aeaa4 (2026-09-16). Data as JSON: /api/errors/0d44f591bd790539. Report an issue: GitHub.

Appendix: source

Thrown at src/sinks/keep/config.rs:188

}
async fn healthcheck(
    endpoint: HttpEndpoint,
    api_key: SensitiveString,
    client: HttpClient,
) -> crate::Result<()> {
    let request =
        Request::post(endpoint.into_v1()).header(HTTP_HEADER_KEEP_API_KEY, api_key.inner());
    let body = crate::serde::json::to_bytes(&Vec::<BoxedRawValue>::new())
        .unwrap()
        .freeze();

    let req: Request<Bytes> = request.body(body)?;
    let req = req.map(full_body);

    let res = client.send(req).await?;

    let status = StatusCode::from_u16(res.status().as_u16())
        .expect("HTTP status codes are valid u16 values");
    let body = res.into_body().collect().await?.to_bytes();

    match status {
        StatusCode::OK => Ok(()),          // Healthcheck passed
        StatusCode::BAD_REQUEST => Ok(()), // Healthcheck failed due to client error but is still considered valid
        StatusCode::ACCEPTED => Ok(()),    // Consider healthcheck passed if server accepted request
        StatusCode::UNAUTHORIZED => {
            // Handle unauthorized errors
            let json: serde_json::Value = serde_json::from_slice(&body[..])?;
            let message = json
                .as_object()
                .and_then(|o| o.get("error"))
                .and_then(|s| s.as_str())
                .unwrap_or("Token is not valid, 401 returned.")
                .to_string();
            Err(message.into())
        }
        _ => {

View on GitHub (pinned to bdb87aeaa4)