searxng/searx/engines/xpath.py
Markus Heiser 8cd544b2a6 [doc] add documentation about the XPath engine
- pylint searx/engines/xpath.py
- fix indentation of some long lines
- add logging
- add doc-strings

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
2021-05-23 11:48:21 +02:00

162 lines
5.0 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
# pylint: disable=missing-function-docstring
"""The XPath engine is a *generic* engine with which it is possible to configure
engines in the settings.
Here is a simple example of a XPath engine configured in the
:ref:`settings engine` section, further read :ref:`engines-dev`.
.. code:: yaml
- name : bitbucket
engine : xpath
paging : True
search_url : https://bitbucket.org/repo/all/{pageno}?name={query}
url_xpath : //article[@class="repo-summary"]//a[@class="repo-link"]/@href
title_xpath : //article[@class="repo-summary"]//a[@class="repo-link"]
content_xpath : //article[@class="repo-summary"]/p
"""
from urllib.parse import urlencode
from lxml import html
from searx.utils import extract_text, extract_url, eval_xpath, eval_xpath_list
from searx import logger
logger = logger.getChild('XPath engine')
search_url = None
"""
Search URL of the engine, replacements are:
``{query}``:
Search terms from user.
``{pageno}``:
Page number if engine supports pagging :py:obj:`paging`
"""
soft_max_redirects = 0
'''Maximum redirects, soft limit. Record an error but don't stop the engine'''
results_xpath = ''
'''XPath selector for the list of result items'''
url_xpath = None
'''XPath selector of result's ``url``.'''
content_xpath = None
'''XPath selector of result's ``content``.'''
title_xpath = None
'''XPath selector of result's ``title``.'''
thumbnail_xpath = False
'''XPath selector of result's ``img_src``.'''
suggestion_xpath = ''
'''XPath selector of result's ``suggestion``.'''
cached_xpath = ''
cached_url = ''
paging = False
'''Engine supports paging [True or False].'''
page_size = 1
'''Number of results on each page. Only needed if the site requires not a page
number, but an offset.'''
first_page_num = 1
'''Number of the first page (usually 0 or 1).'''
def request(query, params):
'''Build request parameters (see :ref:`engine request`).
'''
query = urlencode({'q': query})[2:]
fargs = {'query': query}
if paging and search_url.find('{pageno}') >= 0:
fargs['pageno'] = (params['pageno'] - 1) * page_size + first_page_num
params['url'] = search_url.format(**fargs)
params['query'] = query
params['soft_max_redirects'] = soft_max_redirects
logger.debug("query_url --> %s", params['url'])
return params
def response(resp):
'''Scrap *results* from the response (see :ref:`engine results`).
'''
results = []
dom = html.fromstring(resp.text)
is_onion = 'onions' in categories # pylint: disable=undefined-variable
if results_xpath:
for result in eval_xpath_list(dom, results_xpath):
url = extract_url(eval_xpath_list(result, url_xpath, min_len=1), search_url)
title = extract_text(eval_xpath_list(result, title_xpath, min_len=1))
content = extract_text(eval_xpath_list(result, content_xpath, min_len=1))
tmp_result = {'url': url, 'title': title, 'content': content}
# add thumbnail if available
if thumbnail_xpath:
thumbnail_xpath_result = eval_xpath_list(result, thumbnail_xpath)
if len(thumbnail_xpath_result) > 0:
tmp_result['img_src'] = extract_url(thumbnail_xpath_result, search_url)
# add alternative cached url if available
if cached_xpath:
tmp_result['cached_url'] = (
cached_url
+ extract_text(eval_xpath_list(result, cached_xpath, min_len=1))
)
if is_onion:
tmp_result['is_onion'] = True
results.append(tmp_result)
else:
if cached_xpath:
for url, title, content, cached in zip(
(extract_url(x, search_url) for
x in eval_xpath_list(dom, url_xpath)),
map(extract_text, eval_xpath_list(dom, title_xpath)),
map(extract_text, eval_xpath_list(dom, content_xpath)),
map(extract_text, eval_xpath_list(dom, cached_xpath))
):
results.append({
'url': url,
'title': title,
'content': content,
'cached_url': cached_url + cached, 'is_onion': is_onion
})
else:
for url, title, content in zip(
(extract_url(x, search_url) for
x in eval_xpath_list(dom, url_xpath)),
map(extract_text, eval_xpath_list(dom, title_xpath)),
map(extract_text, eval_xpath_list(dom, content_xpath))
):
results.append({
'url': url,
'title': title,
'content': content,
'is_onion': is_onion
})
if suggestion_xpath:
for suggestion in eval_xpath(dom, suggestion_xpath):
results.append({'suggestion': extract_text(suggestion)})
logger.debug("found %s results", len(results))
return results