searxng/searx/raise_for_httperror.py

# SPDX-License-Identifier: AGPL-3.0-or-later
"""
Raise exception for an HTTP response is an error.
"""
from searx.exceptions import (SearxEngineCaptchaException, SearxEngineTooManyRequestsException,
                              SearxEngineAccessDeniedException)


def is_cloudflare_challenge(resp):
    if resp.status_code in [429, 503]:
        if ('__cf_chl_jschl_tk__=' in resp.text)\
           or ('/cdn-cgi/challenge-platform/' in resp.text
               and 'orchestrate/jsch/v1' in resp.text
               and 'window._cf_chl_enter(' in resp.text):
            return True
    if resp.status_code == 403 and '__cf_chl_captcha_tk__=' in resp.text:
        return True
    return False


def is_cloudflare_firewall(resp):
    return resp.status_code == 403 and '<span class="cf-error-code">1020</span>' in resp.text


def raise_for_cloudflare_captcha(resp):
    if resp.headers.get('Server', '').startswith('cloudflare'):
        if is_cloudflare_challenge(resp):
            # https://support.cloudflare.com/hc/en-us/articles/200170136-Understanding-Cloudflare-Challenge-Passage-Captcha-
            # suspend for 2 weeks
            raise SearxEngineCaptchaException(message='Cloudflare CAPTCHA', suspended_time=3600 * 24 * 15)

        if is_cloudflare_firewall(resp):
            raise SearxEngineAccessDeniedException(message='Cloudflare Firewall', suspended_time=3600 * 24)


def raise_for_recaptcha(resp):
    if resp.status_code == 503 \
       and '"https://www.google.com/recaptcha/' in resp.text:
        raise SearxEngineCaptchaException(message='ReCAPTCHA', suspended_time=3600 * 24 * 7)


def raise_for_captcha(resp):
    raise_for_cloudflare_captcha(resp)
    raise_for_recaptcha(resp)


def raise_for_httperror(resp):
    """Raise exception for an HTTP response is an error.

    Args:
        resp (requests.Response): Response to check

    Raises:
        requests.HTTPError: raise by resp.raise_for_status()
        searx.exceptions.SearxEngineAccessDeniedException: raise when the HTTP status code is 402 or 403.
        searx.exceptions.SearxEngineTooManyRequestsException: raise when the HTTP status code is 429.
        searx.exceptions.SearxEngineCaptchaException: raise when if CATPCHA challenge is detected.
    """
    if resp.status_code and resp.status_code >= 400:
        raise_for_captcha(resp)
        if resp.status_code in (402, 403):
            raise SearxEngineAccessDeniedException(message='HTTP error ' + str(resp.status_code),
                                                   suspended_time=3600 * 24)
        if resp.status_code == 429:
            raise SearxEngineTooManyRequestsException()
        resp.raise_for_status()