searxng/searx/search.py
2016-11-06 02:53:09 +01:00

380 lines
13 KiB
Python

'''
searx is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
searx is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with searx. If not, see < http://www.gnu.org/licenses/ >.
(C) 2013- by Adam Tauber, <asciimoo@gmail.com>
'''
import gc
import threading
from thread import start_new_thread
from time import time
from uuid import uuid4
import searx.poolrequests as requests_lib
from searx.engines import (
categories, engines
)
from searx.utils import gen_useragent
from searx.query import RawTextQuery, SearchQuery
from searx.results import ResultContainer
from searx import logger
from searx.plugins import plugins
logger = logger.getChild('search')
number_of_searches = 0
def search_request_wrapper(fn, url, engine_name, **kwargs):
ret = None
engine = engines[engine_name]
try:
ret = fn(url, **kwargs)
with threading.RLock():
engine.continuous_errors = 0
engine.suspend_end_time = 0
except:
# increase errors stats
with threading.RLock():
engine.stats['errors'] += 1
engine.continuous_errors += 1
engine.suspend_end_time = time() + min(60, engine.continuous_errors)
# print engine name and specific error message
logger.exception('engine crash: {0}'.format(engine_name))
return ret
def threaded_requests(requests):
timeout_limit = max(r[2]['timeout'] for r in requests)
search_start = time()
search_id = uuid4().__str__()
for fn, url, request_args, engine_name in requests:
request_args['timeout'] = timeout_limit
th = threading.Thread(
target=search_request_wrapper,
args=(fn, url, engine_name),
kwargs=request_args,
name=search_id,
)
th._engine_name = engine_name
th.start()
for th in threading.enumerate():
if th.name == search_id:
remaining_time = max(0.0, timeout_limit - (time() - search_start))
th.join(remaining_time)
if th.isAlive():
logger.warning('engine timeout: {0}'.format(th._engine_name))
# get default reqest parameter
def default_request_params():
return {
'method': 'GET',
'headers': {},
'data': {},
'url': '',
'cookies': {},
'verify': True
}
# create a callback wrapper for the search engine results
def make_callback(engine_name, callback, params, result_container):
# creating a callback wrapper for the search engine results
def process_callback(response, **kwargs):
# check if redirect comparing to the True value,
# because resp can be a Mock object, and any attribut name returns something.
if response.is_redirect is True:
logger.debug('{0} redirect on: {1}'.format(engine_name, response))
return
response.search_params = params
search_duration = time() - params['started']
# update stats with current page-load-time
with threading.RLock():
engines[engine_name].stats['page_load_time'] += search_duration
timeout_overhead = 0.2 # seconds
timeout_limit = engines[engine_name].timeout + timeout_overhead
if search_duration > timeout_limit:
with threading.RLock():
engines[engine_name].stats['errors'] += 1
return
# callback
search_results = callback(response)
# add results
for result in search_results:
result['engine'] = engine_name
result_container.extend(engine_name, search_results)
return process_callback
def get_search_query_from_webapp(preferences, form):
query = None
query_engines = []
query_categories = []
query_paging = False
query_pageno = 1
query_lang = 'all'
query_time_range = None
# set blocked engines
disabled_engines = preferences.engines.get_disabled()
# set specific language if set
query_lang = preferences.get_value('language')
# safesearch
query_safesearch = preferences.get_value('safesearch')
# TODO better exceptions
if not form.get('q'):
raise Exception('noquery')
# set pagenumber
pageno_param = form.get('pageno', '1')
if not pageno_param.isdigit() or int(pageno_param) < 1:
pageno_param = 1
query_pageno = int(pageno_param)
# parse query, if tags are set, which change
# the serch engine or search-language
raw_text_query = RawTextQuery(form['q'], disabled_engines)
raw_text_query.parse_query()
# set query
query = raw_text_query.getSearchQuery()
# get last selected language in query, if possible
# TODO support search with multible languages
if len(raw_text_query.languages):
query_lang = raw_text_query.languages[-1]
query_time_range = form.get('time_range')
query_engines = raw_text_query.engines
# if engines are calculated from query,
# set categories by using that informations
if query_engines and raw_text_query.specific:
query_categories = list(set(engine['category']
for engine in query_engines))
# otherwise, using defined categories to
# calculate which engines should be used
else:
# set categories/engines
load_default_categories = True
for pd_name, pd in form.items():
if pd_name == 'categories':
query_categories.extend(categ for categ in map(unicode.strip, pd.split(',')) if categ in categories)
elif pd_name == 'engines':
pd_engines = [{'category': engines[engine].categories[0],
'name': engine}
for engine in map(unicode.strip, pd.split(',')) if engine in engines]
if pd_engines:
query_engines.extend(pd_engines)
load_default_categories = False
elif pd_name.startswith('category_'):
category = pd_name[9:]
# if category is not found in list, skip
if category not in categories:
continue
if pd != 'off':
# add category to list
query_categories.append(category)
elif category in query_categories:
# remove category from list if property is set to 'off'
query_categories.remove(category)
if not load_default_categories:
if not query_categories:
query_categories = list(set(engine['category']
for engine in engines))
else:
# if no category is specified for this search,
# using user-defined default-configuration which
# (is stored in cookie)
if not query_categories:
cookie_categories = preferences.get_value('categories')
for ccateg in cookie_categories:
if ccateg in categories:
query_categories.append(ccateg)
# if still no category is specified, using general
# as default-category
if not query_categories:
query_categories = ['general']
# using all engines for that search, which are
# declared under the specific categories
for categ in query_categories:
query_engines.extend({'category': categ,
'name': engine.name}
for engine in categories[categ]
if (engine.name, categ) not in disabled_engines)
return SearchQuery(query, query_engines, query_categories,
query_lang, query_safesearch, query_pageno, query_time_range)
class Search(object):
"""Search information container"""
def __init__(self, search_query):
# init vars
super(Search, self).__init__()
self.search_query = search_query
self.result_container = ResultContainer()
# do search-request
def search(self):
global number_of_searches
# init vars
requests = []
# increase number of searches
number_of_searches += 1
# set default useragent
# user_agent = request.headers.get('User-Agent', '')
user_agent = gen_useragent()
search_query = self.search_query
# start search-reqest for all selected engines
for selected_engine in search_query.engines:
if selected_engine['name'] not in engines:
continue
engine = engines[selected_engine['name']]
# skip suspended engines
if engine.suspend_end_time >= time():
logger.debug('Engine currently suspended: %s', selected_engine['name'])
continue
# if paging is not supported, skip
if search_query.pageno > 1 and not engine.paging:
continue
# if search-language is set and engine does not
# provide language-support, skip
if search_query.lang != 'all' and not engine.language_support:
continue
# if time_range is not supported, skip
if search_query.time_range and not engine.time_range_support:
continue
# set default request parameters
request_params = default_request_params()
request_params['headers']['User-Agent'] = user_agent
request_params['category'] = selected_engine['category']
request_params['started'] = time()
request_params['pageno'] = search_query.pageno
if hasattr(engine, 'language') and engine.language:
request_params['language'] = engine.language
else:
request_params['language'] = search_query.lang
# 0 = None, 1 = Moderate, 2 = Strict
request_params['safesearch'] = search_query.safesearch
request_params['time_range'] = search_query.time_range
# update request parameters dependent on
# search-engine (contained in engines folder)
engine.request(search_query.query.encode('utf-8'), request_params)
if request_params['url'] is None:
# TODO add support of offline engines
pass
# create a callback wrapper for the search engine results
callback = make_callback(
selected_engine['name'],
engine.response,
request_params,
self.result_container)
# create dictionary which contain all
# informations about the request
request_args = dict(
headers=request_params['headers'],
hooks=dict(response=callback),
cookies=request_params['cookies'],
timeout=engine.timeout,
verify=request_params['verify']
)
# specific type of request (GET or POST)
if request_params['method'] == 'GET':
req = requests_lib.get
else:
req = requests_lib.post
request_args['data'] = request_params['data']
# ignoring empty urls
if not request_params['url']:
continue
# append request to list
requests.append((req, request_params['url'],
request_args,
selected_engine['name']))
if not requests:
return self.result_container
# send all search-request
threaded_requests(requests)
start_new_thread(gc.collect, tuple())
# return results, suggestions, answers and infoboxes
return self.result_container
class SearchWithPlugins(Search):
"""Similar to the Search class but call the plugins."""
def __init__(self, search_query, request):
super(SearchWithPlugins, self).__init__(search_query)
self.request = request
def search(self):
if plugins.call('pre_search', self.request, self):
super(SearchWithPlugins, self).search()
plugins.call('post_search', self.request, self)
results = self.result_container.get_ordered_results()
for result in results:
plugins.call('on_result', self.request, self, result)
return self.result_container