searxng/searx/engines/xpath.py
2017-01-17 21:14:33 +10:00

122 lines
3.6 KiB
Python

from lxml import html
from urllib import urlencode, unquote
from urlparse import urlparse, urljoin
from lxml.etree import _ElementStringResult, _ElementUnicodeResult
from searx.utils import html_to_text
search_url = None
url_xpath = None
content_xpath = None
title_xpath = None
suggestion_xpath = ''
results_xpath = ''
# parameters for engines with paging support
#
# number of results on each page
# (only needed if the site requires not a page number, but an offset)
page_size = 1
# number of the first page (usually 0 or 1)
first_page_num = 1
'''
if xpath_results is list, extract the text from each result and concat the list
if xpath_results is a xml element, extract all the text node from it
( text_content() method from lxml )
if xpath_results is a string element, then it's already done
'''
def extract_text(xpath_results):
if type(xpath_results) == list:
# it's list of result : concat everything using recursive call
result = ''
for e in xpath_results:
result = result + extract_text(e)
return result.strip()
elif type(xpath_results) in [_ElementStringResult, _ElementUnicodeResult]:
# it's a string
return ''.join(xpath_results)
else:
# it's a element
text = html.tostring(xpath_results, encoding='unicode', method='text', with_tail=False)
text = text.strip().replace('\n', ' ')
return ' '.join(text.split())
def extract_url(xpath_results, search_url):
if xpath_results == []:
raise Exception('Empty url resultset')
url = extract_text(xpath_results)
if url.startswith('//'):
# add http or https to this kind of url //example.com/
parsed_search_url = urlparse(search_url)
url = parsed_search_url.scheme + url
elif url.startswith('/'):
# fix relative url to the search engine
url = urljoin(search_url, url)
# normalize url
url = normalize_url(url)
return url
def normalize_url(url):
parsed_url = urlparse(url)
# add a / at this end of the url if there is no path
if not parsed_url.netloc:
raise Exception('Cannot parse url')
if not parsed_url.path:
url += '/'
# FIXME : hack for yahoo
if parsed_url.hostname == 'search.yahoo.com'\
and parsed_url.path.startswith('/r'):
p = parsed_url.path
mark = p.find('/**')
if mark != -1:
return unquote(p[mark + 3:]).decode('utf-8')
return url
def request(query, params):
query = urlencode({'q': query})[2:]
fp = {'query': query}
if paging and search_url.find('{pageno}') >= 0:
fp['pageno'] = (params['pageno'] - 1) * page_size + first_page_num
params['url'] = search_url.format(**fp)
params['query'] = query
return params
def response(resp):
results = []
dom = html.fromstring(resp.text)
if results_xpath:
for result in dom.xpath(results_xpath):
url = extract_url(result.xpath(url_xpath), search_url)
title = extract_text(result.xpath(title_xpath))
content = extract_text(result.xpath(content_xpath))
results.append({'url': url, 'title': title, 'content': content})
else:
for url, title, content in zip(
(extract_url(x, search_url) for
x in dom.xpath(url_xpath)),
map(extract_text, dom.xpath(title_xpath)),
map(extract_text, dom.xpath(content_xpath))
):
results.append({'url': url, 'title': title, 'content': content})
if not suggestion_xpath:
return results
for suggestion in dom.xpath(suggestion_xpath):
results.append({'suggestion': extract_text(suggestion)})
return results