searxng/searx/engines/startpage.py
Markus Heiser df238e944c [mod] starpage engine: add comment about Startpage's FFox add-on
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
2022-01-10 11:22:38 +01:00

263 lines
8.6 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
"""Startpage (Web)
"""
import re
from time import time
from urllib.parse import urlencode
from unicodedata import normalize, combining
from datetime import datetime, timedelta
from dateutil import parser
from lxml import html
from babel import Locale
from babel.localedata import locale_identifiers
from searx import network
from searx.utils import extract_text, eval_xpath, match_language
from searx.exceptions import (
SearxEngineResponseException,
SearxEngineCaptchaException,
)
# about
about = {
"website": 'https://startpage.com',
"wikidata_id": 'Q2333295',
"official_api_documentation": None,
"use_official_api": False,
"require_api_key": False,
"results": 'HTML',
}
# engine dependent config
categories = ['general', 'web']
# there is a mechanism to block "bot" search
# (probably the parameter qid), require
# storing of qid's between mulitble search-calls
paging = True
supported_languages_url = 'https://www.startpage.com/do/settings'
# search-url
base_url = 'https://startpage.com/'
search_url = base_url + 'sp/search?'
# specific xpath variables
# ads xpath //div[@id="results"]/div[@id="sponsored"]//div[@class="result"]
# not ads: div[@class="result"] are the direct childs of div[@id="results"]
results_xpath = '//div[@class="w-gl__result__main"]'
link_xpath = './/a[@class="w-gl__result-title result-link"]'
content_xpath = './/p[@class="w-gl__description"]'
# timestamp of the last fetch of 'sc' code
sc_code_ts = 0
sc_code = ''
def raise_captcha(resp):
if str(resp.url).startswith('https://www.startpage.com/sp/captcha'):
# suspend CAPTCHA for 7 days
raise SearxEngineCaptchaException(suspended_time=7 * 24 * 3600)
def get_sc_code(headers):
"""Get an actual `sc` argument from startpage's home page.
Startpage puts a `sc` argument on every link. Without this argument
startpage considers the request is from a bot. We do not know what is
encoded in the value of the `sc` argument, but it seems to be a kind of a
*time-stamp*. This *time-stamp* is valid for a few hours.
This function scrap a new *time-stamp* from startpage's home page every hour
(3000 sec).
"""
global sc_code_ts, sc_code # pylint: disable=global-statement
if time() > (sc_code_ts + 3000):
logger.debug("query new sc time-stamp ...")
resp = network.get(base_url, headers=headers)
raise_captcha(resp)
dom = html.fromstring(resp.text)
try:
# href --> '/?sc=adrKJMgF8xwp20'
href = eval_xpath(dom, '//a[@class="footer-home__logo"]')[0].get('href')
except IndexError as exc:
# suspend startpage API --> https://github.com/searxng/searxng/pull/695
raise SearxEngineResponseException(
suspended_time=7 * 24 * 3600, message="PR-695: query new sc time-stamp failed!"
) from exc
sc_code = href[5:]
sc_code_ts = time()
logger.debug("new value is: %s", sc_code)
return sc_code
# do search-request
def request(query, params):
# pylint: disable=line-too-long
# The format string from Startpage's FFox add-on [1]::
#
# https://www.startpage.com/do/dsearch?query={searchTerms}&cat=web&pl=ext-ff&language=__MSG_extensionUrlLanguage__&extVersion=1.3.0
#
# [1] https://addons.mozilla.org/en-US/firefox/addon/startpage-private-search/
args = {
'query': query,
'page': params['pageno'],
'cat': 'web',
# 'pl': 'ext-ff',
# 'extVersion': '1.3.0',
# 'abp': "-1",
'sc': get_sc_code(params['headers']),
}
# set language if specified
if params['language'] != 'all':
lang_code = match_language(params['language'], supported_languages, fallback=None)
if lang_code:
language_name = supported_languages[lang_code]['alias']
args['language'] = language_name
args['lui'] = language_name
params['url'] = search_url + urlencode(args)
return params
# get response from search-request
def response(resp):
results = []
dom = html.fromstring(resp.text)
# parse results
for result in eval_xpath(dom, results_xpath):
links = eval_xpath(result, link_xpath)
if not links:
continue
link = links[0]
url = link.attrib.get('href')
# block google-ad url's
if re.match(r"^http(s|)://(www\.)?google\.[a-z]+/aclk.*$", url):
continue
# block startpage search url's
if re.match(r"^http(s|)://(www\.)?startpage\.com/do/search\?.*$", url):
continue
title = extract_text(link)
if eval_xpath(result, content_xpath):
content = extract_text(eval_xpath(result, content_xpath))
else:
content = ''
published_date = None
# check if search result starts with something like: "2 Sep 2014 ... "
if re.match(r"^([1-9]|[1-2][0-9]|3[0-1]) [A-Z][a-z]{2} [0-9]{4} \.\.\. ", content):
date_pos = content.find('...') + 4
date_string = content[0 : date_pos - 5]
# fix content string
content = content[date_pos:]
try:
published_date = parser.parse(date_string, dayfirst=True)
except ValueError:
pass
# check if search result starts with something like: "5 days ago ... "
elif re.match(r"^[0-9]+ days? ago \.\.\. ", content):
date_pos = content.find('...') + 4
date_string = content[0 : date_pos - 5]
# calculate datetime
published_date = datetime.now() - timedelta(days=int(re.match(r'\d+', date_string).group()))
# fix content string
content = content[date_pos:]
if published_date:
# append result
results.append({'url': url, 'title': title, 'content': content, 'publishedDate': published_date})
else:
# append result
results.append({'url': url, 'title': title, 'content': content})
# return results
return results
# get supported languages from their site
def _fetch_supported_languages(resp):
# startpage's language selector is a mess each option has a displayed name
# and a value, either of which may represent the language name in the native
# script, the language name in English, an English transliteration of the
# native name, the English name of the writing script used by the language,
# or occasionally something else entirely.
# this cases are so special they need to be hardcoded, a couple of them are mispellings
language_names = {
'english_uk': 'en-GB',
'fantizhengwen': ['zh-TW', 'zh-HK'],
'hangul': 'ko',
'malayam': 'ml',
'norsk': 'nb',
'sinhalese': 'si',
'sudanese': 'su',
}
# get the English name of every language known by babel
language_names.update(
{
# fmt: off
name.lower(): lang_code
# pylint: disable=protected-access
for lang_code, name in Locale('en')._data['languages'].items()
# fmt: on
}
)
# get the native name of every language known by babel
for lang_code in filter(lambda lang_code: lang_code.find('_') == -1, locale_identifiers()):
native_name = Locale(lang_code).get_language_name().lower()
# add native name exactly as it is
language_names[native_name] = lang_code
# add "normalized" language name (i.e. français becomes francais and español becomes espanol)
unaccented_name = ''.join(filter(lambda c: not combining(c), normalize('NFKD', native_name)))
if len(unaccented_name) == len(unaccented_name.encode()):
# add only if result is ascii (otherwise "normalization" didn't work)
language_names[unaccented_name] = lang_code
dom = html.fromstring(resp.text)
sp_lang_names = []
for option in dom.xpath('//form[@id="settings-form"]//select[@name="language"]/option'):
sp_lang_names.append((option.get('value'), extract_text(option).lower()))
supported_languages = {}
for sp_option_value, sp_option_text in sp_lang_names:
lang_code = language_names.get(sp_option_value) or language_names.get(sp_option_text)
if isinstance(lang_code, str):
supported_languages[lang_code] = {'alias': sp_option_value}
elif isinstance(lang_code, list):
for _lc in lang_code:
supported_languages[_lc] = {'alias': sp_option_value}
else:
print('Unknown language option in Startpage: {} ({})'.format(sp_option_value, sp_option_text))
return supported_languages