ZhuLinsen/daily_stock_analysis · error · DataFetchError

[AlphaVantage] API error for {symbol}: {data['Error Message'

Error message

[AlphaVantage] API error for {symbol}: {data['Error Message']}

What it means

A DataFetchError raised by AlphaVantageFetcher._fetch_raw_data when the JSON response contains an 'Error Message' key. AlphaVantage uses this field (with HTTP 200) for hard API-level failures — most commonly an invalid or unknown symbol, but also invalid function parameters or a malformed apikey.

Source

Thrown at data_provider/alphavantage_fetcher.py:66

        params = {
            'function': 'TIME_SERIES_DAILY',
            'symbol': symbol,
            'outputsize': 'compact',
            'apikey': self._api_key,
        }

        try:
            self.random_sleep(0.5, 1.5)
            resp = requests.get(_AV_BASE_URL, params=params, timeout=30)
            resp.raise_for_status()
            data = resp.json()
        except Exception as e:
            raise DataFetchError(f"[AlphaVantage] HTTP request failed for {symbol}: {e}") from e

        if 'Note' in data:
            raise DataFetchError(f"[AlphaVantage] Rate limited: {data['Note']}")
        if 'Error Message' in data:
            raise DataFetchError(f"[AlphaVantage] API error for {symbol}: {data['Error Message']}")

        ts_key = 'Time Series (Daily)'
        if ts_key not in data or not data[ts_key]:
            raise DataFetchError(f"[AlphaVantage] No time series data for {symbol}")

        rows = []
        start = datetime.strptime(start_date, '%Y-%m-%d').date()
        end = datetime.strptime(end_date, '%Y-%m-%d').date()
        for date_str, values in data[ts_key].items():
            row_date = datetime.strptime(date_str, '%Y-%m-%d').date()
            if start <= row_date <= end:
                rows.append({
                    'date': date_str,
                    '1. open': float(values.get('1. open', 0)),
                    '2. high': float(values.get('2. high', 0)),
                    '3. low': float(values.get('3. low', 0)),
                    '4. close': float(values.get('4. close', 0)),
                    '5. volume': float(values.get('5. volume', 0)),

View on GitHub (pinned to 5159bd72e8)

Solutions

  1. Read the embedded Error Message — AV states the exact reason ('Invalid API call ... symbol').
  2. Validate the symbol exists on AlphaVantage (test with the demo IBM call pattern) before adding it to batch jobs.
  3. Strip whitespace from the API key and re-copy it from the AV dashboard.
  4. Treat as permanent for that symbol: exclude it from AV routing and use a market-appropriate source.

Example fix

# before
syms = ['AAPL', 'APPL', 'BRK.B']  # typos/unsupported
for s in syms:
    df = av_fetcher.fetch(s, start, end)  # dies on 'APPL'

# after
for s in syms:
    try:
        df = av_fetcher.fetch(s, start, end)
    except DataFetchError as e:
        if 'API error' in str(e):
            logger.warning('skip invalid symbol %s: %s', s, e)
            continue
Defensive patterns

Strategy: try-catch

Validate before calling

import requests, os
r = requests.get('https://www.alphavantage.co/query', params={
    'function': 'TIME_SERIES_DAILY', 'symbol': sym,
    'apikey': os.environ['ALPHAVANTAGE_API_KEY']}, timeout=10)
data = r.json()
if 'Error Message' in data:
    raise ValueError(f'symbol {sym} rejected by AlphaVantage: {data["Error Message"]}')

Try / catch

try:
    df = av_fetcher.fetch(sym, start, end)
except DataFetchError as e:
    if 'API error' in str(e):
        logger.warning('permanently skipping invalid symbol %s: %s', sym, e)
        continue
    raise

Prevention

When it happens

Trigger: Requesting a symbol AV does not recognize (typo like 'APPL', delisted ticker, or a non-US symbol that slipped past the is_us_stock_code guard); passing an invalid parameter; a truncated/invalid API key that passes the not-empty check but is rejected by the service.

Common situations: Watchlists with stale/delisted tickers; symbols with dots or share classes ('BRK.B') that AV rejects; copy-pasted key with whitespace; ADR/OTC tickers unsupported by TIME_SERIES_DAILY.

Related errors

AI-assisted analysis of ZhuLinsen/daily_stock_analysis@5159bd72e8 (2026-08-15). Data as JSON: /api/errors/c2fd0b438a693d4e. Report an issue: GitHub.