OpenBB-finance/OpenBB · error · OpenBBError

Invalid JSON response from ECB

Error message

Invalid JSON response from ECB

What it means

Raised in the ECB shared helper (ecb_helpers.py) when amake_request against https://data.ecb.europa.eu/data-detail-api/{series_id} succeeds at the HTTP level but the body is not valid JSON — json.JSONDecodeError is caught and re-wrapped as OpenBBError('Invalid JSON response from ECB').

Source

Thrown at openbb_platform/providers/ecb/openbb_ecb/utils/ecb_helpers.py:33

    """
    # pylint: disable=import-outside-toplevel
    import json  # noqa
    from openbb_core.app.model.abstract.error import OpenBBError  # noqa
    from openbb_core.provider.utils.helpers import amake_request  # noqa

    start_date = start_date.replace("-", "")
    end_date = end_date.replace("-", "")
    url = f"https://data.ecb.europa.eu/data-detail-api/{series_id}"
    data: list = []  # type: ignore
    try:
        data = await amake_request(  # type: ignore
            url=url,
            params={"startPeriod": start_date, "endPeriod": end_date},
        )
    except KeyboardInterrupt as interrupt:
        raise interrupt
    except json.JSONDecodeError as exc:
        raise OpenBBError("Invalid JSON response from ECB") from exc

    if start_date:
        data = [item for item in data if item["PERIOD"][0] >= start_date]
    if end_date:
        data = [item for item in data if item["PERIOD"][0] <= end_date]

    return data

View on GitHub (pinned to 3e071fcc2c)

Solutions

1. Retry with backoff — transient truncation/HTML error pages usually resolve.
2. curl the same URL with the startPeriod/endPeriod params and inspect Content-Type/body to confirm what ECB is returning.
3. Bypass corporate proxy or configure HTTPS_PROXY properly if a TLS-intercepting proxy is mangling bodies.
4. Update the openbb-ecb provider in case the endpoint changed and now returns a different error contract.

Example fix

# before
res = obb.fixedincome.government_yield_curve(provider="ecb")

# after
import time
from openbb_core.provider.utils.errors import OpenBBError
for attempt in range(3):
    try:
        res = obb.fixedincome.government_yield_curve(provider="ecb", use_cache=False)
        break
    except OpenBBError as e:
        if "Invalid JSON" in str(e) and attempt < 2:
            time.sleep(2 ** attempt)
            continue
        raise

import requests

def ecb_api_returns_json(series_id: str) -> bool:
    r = requests.get(f"https://data.ecb.europa.eu/data-detail-api/{series_id}", timeout=15)
    return "json" in r.headers.get("content-type", "") and r.text.lstrip()[:1] in "[{"

import time
from openbb_core.provider.utils.errors import OpenBBError
for attempt in range(3):
    try:
        res = fetch_ecb(series_id)
        break
    except OpenBBError as e:
        if "Invalid JSON" in str(e) and attempt < 2:
            time.sleep(2 ** attempt)
            continue
        raise

When it happens

Trigger: ECB serves an HTML error/maintenance page or truncated body where the client expects JSON; a proxy or captive portal injects HTML; content-encoding corruption. Any ECB model that uses this helper (yield curve, balance of payments, etc.) can surface it.

Common situations: ECB portal incidents or CDN edge errors returning HTML 200s; corporate TLS-inspecting proxies rewriting responses; flaky mobile/high-latency networks truncating chunked responses.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• Error fetching data: {e}
• Failed to fetch data from ECB. -> Status Code: {response.sta
• Unexpected response format when fetching constraints {datafl
• Failed to parse XML response: {url} -> {e}
• Method must be GET or POST

AI-assisted analysis of OpenBB-finance/OpenBB@3e071fcc2c (2026-08-14). Data as JSON: /api/errors/a2ea89995ac71605. Report an issue: GitHub.