jackwener/OpenCLI · error · CommandExecutionError

${label} request failed: ${error instanceof Error ? error.me

Error message

${label} request failed: ${error instanceof Error ? error.message : String(error)}

What it means

fetchJson performs an HTTP GET with a WeRead User-Agent and wraps low-level fetch failures (network errors) in CommandExecutionError with the '<label> request failed:' prefix. This is thrown when the request never completes — DNS failure, connection refused/reset, TLS errors, or timeouts — before any HTTP status is received.

Source

Thrown at clis/weread/book-search.js:85

    const pathParts = url.pathname.split('/').filter(Boolean);
    if (url.protocol !== 'https:' || url.hostname !== 'weread.qq.com' || pathParts[0] !== 'web' || pathParts[1] !== 'reader' || !pathParts[2]) {
        return '';
    }
    if (pathParts.length !== 3) {
        return '';
    }
    return url.toString();
}

async function fetchJson(url, label) {
    let resp;
    try {
        resp = await fetch(url.toString(), {
            headers: { 'User-Agent': WEREAD_UA },
        });
    }
    catch (error) {
        throw new CommandExecutionError(`${label} request failed: ${error instanceof Error ? error.message : String(error)}`);
    }
    if (!resp.ok) {
        throw new CommandExecutionError(`${label} request failed: HTTP ${resp.status}`);
    }
    try {
        return await resp.json();
    }
    catch {
        throw new CommandExecutionError(`${label} returned invalid JSON`);
    }
}

async function fetchText(url, label) {
    let resp;
    try {
        resp = await fetch(url.toString(), {
            headers: { 'User-Agent': WEREAD_UA },
        });

View on GitHub (pinned to 49907e53dc)

Solutions

Verify network connectivity (curl the URL or ping the host)
Check proxy environment variables (HTTPS_PROXY) and corporate CA configuration
Retry — transient DNS/connection failures often resolve on retry
If behind a firewall, allowlist the WeRead web origin
Inspect the inner error message after 'request failed:' to identify the root cause

Example fix

// before (no retry, hard fail)
const data = await fetchJson(url, 'WeRead book search');
// after (retry transient failures)
for (let attempt = 1; attempt <= 3; attempt++) {
  try { return await fetchJson(url, 'WeRead book search'); }
  catch (e) { if (attempt === 3) throw e; await sleep(500 * attempt); }
}

Defensive patterns

Strategy: retry

Validate before calling

// Reachability probe before the real call
const probe = await fetch(WEREAD_WEB_ORIGIN, { method: 'HEAD' }).catch(() => null);
if (!probe) throw new Error('WeRead origin unreachable; check network/VPN/proxy');

Type guard

null

Try / catch

try {
  const data = await fetchJson(url, 'WeRead book search');
} catch (e) {
  if (e instanceof CommandExecutionError && e.message.includes('request failed:') && !e.message.includes('HTTP')) {
    // network-layer failure: retry with backoff
    for (let i = 1; i <= 3; i++) { await sleep(500 * 2 ** i); /* retry */ }
  } else throw e;
}

Prevention

Wrap all network calls in retry-with-backoff helpers
Check VPN/proxy environment (HTTPS_PROXY, corporate CA) before running in restricted networks
Distinguish network failures from HTTP status failures by inspecting the message
Prefer resolving the hostname once (dns lookup) to catch DNS issues early

When it happens

Trigger: The machine is offline, DNS cannot resolve the WeRead host, a proxy/firewall blocks the connection, fetch() rejects (ECONNREFUSED, ENOTFOUND, ETIMEDOUT, certificate errors), or an invalid URL string produces a throw inside the fetch call.

Common situations: Corporate proxies with MITM certificates, VPN required for access, Wi-Fi captive portals, IPv6 misconfiguration, or the WeRead endpoint being temporarily unreachable.

Understand the failure class

Background: 'Something went wrong' / 'Request failed (500)' / 'HTTP error! status: 404' — what failed HTTP requests actually mean and how to find the real cause — this error's family across 28 libraries.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/f2de05a19f49c16d. Report an issue: GitHub.