jackwener/OpenCLI · warning · EmptyResultError

coingecko derivatives

Error message

coingecko derivatives

What it means

EmptyResultError raised when the /derivatives endpoint returns valid JSON that is not a non-empty array. The library treats an empty or wrongly-shaped payload as 'no derivative tickers available' and signals it distinctly from a transport failure.

Source

Thrown at clis/coingecko/derivatives.js:60

        }
        if (resp.status === 429) {
            throw new CommandExecutionError(
                'coingecko derivatives returned HTTP 429 (rate limited)',
                'Free tier allows ~30 calls/min. Wait and retry.',
            );
        }
        if (!resp.ok) {
            throw new CommandExecutionError(`coingecko derivatives returned HTTP ${resp.status}`);
        }
        let data;
        try {
            data = await resp.json();
        }
        catch (err) {
            throw new CommandExecutionError(`coingecko derivatives returned malformed JSON: ${err?.message ?? err}`);
        }
        if (!Array.isArray(data) || !data.length) {
            throw new EmptyResultError('coingecko derivatives', 'CoinGecko returned no derivative tickers.');
        }
        let rows = data;
        if (filter) {
            rows = data.filter((d) => String(d.symbol ?? '').toUpperCase().includes(filter)
                || String(d.index_id ?? '').toUpperCase().includes(filter));
            if (!rows.length) {
                throw new EmptyResultError('coingecko derivatives', `No derivative tickers matched symbol="${filter}".`);
            }
        }
        return rows.slice(0, limit).map((d, i) => ({
            rank: i + 1,
            market: String(d.market ?? ''),
            symbol: String(d.symbol ?? ''),
            indexId: String(d.index_id ?? ''),
            contractType: String(d.contract_type ?? ''),
            price: d.price != null ? Number(d.price) : null,
            change24hPct: d.price_percentage_change_24h != null ? Number(d.price_percentage_change_24h) : null,
            fundingRate: d.funding_rate != null ? Number(d.funding_rate) : null,

View on GitHub (pinned to 49907e53dc)

Solutions

  1. Retry shortly — a transient empty payload often resolves.
  2. Call the endpoint directly (curl) and inspect the JSON shape to confirm whether it is [] or a schema change.
  3. Check CoinGecko status page / changelog for API schema or endpoint changes.
  4. Pin to a known-good API version or add a Pro API key for more stable service.
  5. If schema changed, update the CLI's mapping code to the new response format.

Example fix

// before
const rows = await runCli(['coingecko', 'derivatives']);
// after
try {
  const rows = await runCli(['coingecko', 'derivatives']);
} catch (err) {
  if (err.name === 'EmptyResultError') {
    return []; // treat 'no tickers' as an empty dataset, not a crash
  }
  throw err;
}
Defensive patterns

Strategy: type-guard

Validate before calling

const resp = await fetch('https://api.coingecko.com/api/v3/derivatives');
const data = await resp.json();
if (!Array.isArray(data)) console.warn('Unexpected /derivatives schema:', typeof data, data);

Type guard

function hasDerivatives(v) {
  return Array.isArray(v) && v.length > 0 && typeof v[0] === 'object' && v[0] !== null && 'symbol' in v[0];
}

Try / catch

try {
  const rows = await runCli(['coingecko', 'derivatives']);
} catch (err) {
  if (err.name === 'EmptyResultError') return []; // empty dataset, not fatal
  throw err;
}

Prevention

When it happens

Trigger: API responds 200 with [] (no derivatives listed), or with a non-array JSON value such as {status: {...}} error object, null, or a string — e.g. an undocumented API schema change or a JSON error body that CoinGecko still serves with HTTP 200.

Common situations: CoinGecko quietly changing the /derivatives response shape; an outage page returning a JSON error object with 200; temporarily empty dataset during maintenance; caller parsing a cached/stale proxy response.

Understand the failure class

Background: EmptyResultError / "no results found": when an API or scraper succeeds but returns zero rows — this error's family across 9 libraries.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/5293b936e8d8988b. Report an issue: GitHub.