add comments to search.py

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* add comments
* add licence-header
This commit is contained in:
Thomas Pointhuber 2014-09-13 18:25:25 +02:00
parent d23dd7e276
commit c9bab0e833
1 changed files with 118 additions and 0 deletions
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118
searx/search.py
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@ -1,3 +1,20 @@
'''
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 grequests
from itertools import izip_longest, chain
from datetime import datetime
@ -9,46 +26,67 @@ from searx.engines import (
from searx.languages import language_codes
from searx.utils import gen_useragent
number_of_searches = 0
# get default reqest parameter
def default_request_params():
return {
'method': 'GET', 'headers': {}, 'data': {}, 'url': '', 'cookies': {}}
# create a callback wrapper for the search engine results
def make_callback(engine_name, results, suggestions, callback, params):
# creating a callback wrapper for the search engine results
def process_callback(response, **kwargs):
cb_res = []
response.search_params = params
# update stats with current page-load-time
engines[engine_name].stats['page_load_time'] += \
(datetime.now() - params['started']).total_seconds()
try:
search_results = callback(response)
except Exception, e:
# increase errors stats
engines[engine_name].stats['errors'] += 1
results[engine_name] = cb_res
# print engine name and specific error message
print '[E] Error with engine "{0}":\n\t{1}'.format(
engine_name, str(e))
return
for result in search_results:
result['engine'] = engine_name
# if it is a suggestion, add it to list of suggestions
if 'suggestion' in result:
# TODO type checks
suggestions.add(result['suggestion'])
continue
# append result
cb_res.append(result)
results[engine_name] = cb_res
return process_callback
# score results and remove duplications
def score_results(results):
# calculate scoring parameters
flat_res = filter(
None, chain.from_iterable(izip_longest(*results.values())))
flat_len = len(flat_res)
engines_len = len(results)
results = []
# deduplication + scoring
for i, res in enumerate(flat_res):
@ -62,34 +100,54 @@ def score_results(results):
res['engines'] = [res['engine']]
weight = 1.0
# get weight of this engine if possible
if hasattr(engines[res['engine']], 'weight'):
weight = float(engines[res['engine']].weight)
# calculate score for that engine
score = int((flat_len - i) / engines_len) * weight + 1
duplicated = False
# check for duplicates
for new_res in results:
# remove / from the end of the url if required
p1 = res['parsed_url'].path[:-1] if res['parsed_url'].path.endswith('/') else res['parsed_url'].path # noqa
p2 = new_res['parsed_url'].path[:-1] if new_res['parsed_url'].path.endswith('/') else new_res['parsed_url'].path # noqa
# check if that result is a duplicate
if res['host'] == new_res['host'] and\
unquote(p1) == unquote(p2) and\
res['parsed_url'].query == new_res['parsed_url'].query and\
res.get('template') == new_res.get('template'):
duplicated = new_res
break
# merge duplicates together
if duplicated:
# using content with more text
if res.get('content') > duplicated.get('content'):
duplicated['content'] = res['content']
# increase result-score
duplicated['score'] += score
# add engine to list of result-engines
duplicated['engines'].append(res['engine'])
# using https if possible
if duplicated['parsed_url'].scheme == 'https':
continue
elif res['parsed_url'].scheme == 'https':
duplicated['url'] = res['parsed_url'].geturl()
duplicated['parsed_url'] = res['parsed_url']
# if there is no duplicate found, append result
else:
res['score'] = score
results.append(res)
# return results sorted by score
return sorted(results, key=itemgetter('score'), reverse=True)
@ -98,6 +156,7 @@ class Search(object):
"""Search information container"""
def __init__(self, request):
# init vars
super(Search, self).__init__()
self.query = None
self.engines = []
@ -105,18 +164,23 @@ class Search(object):
self.paging = False
self.pageno = 1
self.lang = 'all'
# set blocked engines
if request.cookies.get('blocked_engines'):
self.blocked_engines = request.cookies['blocked_engines'].split(',') # noqa
else:
self.blocked_engines = []
self.results = []
self.suggestions = []
self.request_data = {}
# set specific language if set
if request.cookies.get('language')\
and request.cookies['language'] in (x[0] for x in language_codes):
self.lang = request.cookies['language']
# set request method
if request.method == 'POST':
self.request_data = request.form
else:
@ -126,51 +190,72 @@ class Search(object):
if not self.request_data.get('q'):
raise Exception('noquery')
# set query
self.query = self.request_data['q']
# set pagenumber
pageno_param = self.request_data.get('pageno', '1')
if not pageno_param.isdigit() or int(pageno_param) < 1:
raise Exception('wrong pagenumber')
self.pageno = int(pageno_param)
# parse query, if tags are set, which change the serch engine or search-language
self.parse_query()
self.categories = []
# if engines are calculated from query, set categories by using that informations
if self.engines:
self.categories = list(set(engine['category']
for engine in self.engines))
# otherwise, using defined categories to calculate which engines should be used
else:
# set used categories
for pd_name, pd in self.request_data.items():
if pd_name.startswith('category_'):
category = pd_name[9:]
# if category is not found in list, skip
if not category in categories:
continue
# add category to list
self.categories.append(category)
# if no category is specified for this search, using user-defined default-configuration which (is stored in cookie)
if not self.categories:
cookie_categories = request.cookies.get('categories', '')
cookie_categories = cookie_categories.split(',')
for ccateg in cookie_categories:
if ccateg in categories:
self.categories.append(ccateg)
# if still no category is specified, using general as default-category
if not self.categories:
self.categories = ['general']
# using all engines for that search, which are declared under the specific categories
for categ in self.categories:
self.engines.extend({'category': categ,
'name': x.name}
for x in categories[categ]
if not x.name in self.blocked_engines)
# parse query, if tags are set, which change the serch engine or search-language
def parse_query(self):
query_parts = self.query.split()
modified = False
# check if language-prefix is set
if query_parts[0].startswith(':'):
lang = query_parts[0][1:].lower()
# check if any language-code equal with declared language-codes
for lc in language_codes:
lang_id, lang_name, country = map(str.lower, lc)
# if correct language-code is found, set it as new search-language
if lang == lang_id\
or lang_id.startswith(lang)\
or lang == lang_name\
@ -179,56 +264,78 @@ class Search(object):
modified = True
break
# check if category/engine prefix is set
elif query_parts[0].startswith('!'):
prefix = query_parts[0][1:].replace('_', ' ')
# check if prefix equal with engine shortcut
if prefix in engine_shortcuts\
and not engine_shortcuts[prefix] in self.blocked_engines:
modified = True
self.engines.append({'category': 'none',
'name': engine_shortcuts[prefix]})
# check if prefix equal with engine name
elif prefix in engines\
and not prefix in self.blocked_engines:
modified = True
self.engines.append({'category': 'none',
'name': prefix})
# check if prefix equal with categorie name
elif prefix in categories:
modified = True
# using all engines for that search, which are declared under that categorie name
self.engines.extend({'category': prefix,
'name': engine.name}
for engine in categories[prefix]
if not engine in self.blocked_engines)
# if language, category or engine were specificed in this query, search for more tags which does the same
if modified:
self.query = self.query.replace(query_parts[0], '', 1).strip()
self.parse_query()
# do search-request
def search(self, request):
global number_of_searches
# init vars
requests = []
results = {}
suggestions = set()
# increase number of active searches
number_of_searches += 1
# set default useragent
#user_agent = request.headers.get('User-Agent', '')
user_agent = gen_useragent()
# start search-reqest for all selected engines
for selected_engine in self.engines:
if selected_engine['name'] not in engines:
continue
engine = engines[selected_engine['name']]
# if paging is not supported, skip
if self.pageno > 1 and not engine.paging:
continue
# if search-language is set and engine does not provide language-support, skip
if self.lang != 'all' and not engine.language_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'] = datetime.now()
request_params['pageno'] = self.pageno
request_params['language'] = self.lang
# update request parameters dependent on search-engine (contained in engines folder)
request_params = engine.request(self.query.encode('utf-8'),
request_params)
@ -236,6 +343,7 @@ class Search(object):
# TODO add support of offline engines
pass
# create a callback wrapper for the search engine results
callback = make_callback(
selected_engine['name'],
results,
@ -244,6 +352,7 @@ class Search(object):
request_params
)
# create dictionary which contain all informations about the request
request_args = dict(
headers=request_params['headers'],
hooks=dict(response=callback),
@ -251,6 +360,7 @@ class Search(object):
timeout=engine.timeout
)
# specific type of request (GET or POST)
if request_params['method'] == 'GET':
req = grequests.get
else:
@ -261,17 +371,25 @@ class Search(object):
if not request_params['url']:
continue
# append request to list
requests.append(req(request_params['url'], **request_args))
# send all search-request
grequests.map(requests)
# update engine-specific stats
for engine_name, engine_results in results.items():
engines[engine_name].stats['search_count'] += 1
engines[engine_name].stats['result_count'] += len(engine_results)
# score results and remove duplications
results = score_results(results)
# update engine stats, using calculated score
for result in results:
for res_engine in result['engines']:
engines[result['engine']]\
.stats['score_count'] += result['score']
# return results and suggestions
return results, suggestions