Simplify search.py, basically updated PR #518

The timeouts in settings.yml is about the total time (not only the HTTP request but also the prepare the request and parsing the response)
It was more or less the case before since the threaded_requests function ignores the thread after the timeout even the HTTP request is ended.

New / changed stats :
* page_load_time : record the HTTP request time
* page_load_count: the number of HTTP request
* engine_time : the execution total time of an engine
* engine_time_count : the number of "engine_time" measure

The avg response times in the preferences are the engine response time (engine_load_time / engine_load_count)

To sum up :
* Search.search() filters the engines that can't process the request
* Search.search() call search_multiple_requests function
* search_multiple_requests creates one thread per engine, each thread runs the search_one_request function
* search_one_request calls the request function, make the HTTP request, calls the response function, extends the result_container
* search_multiple_requests waits for the the thread to finish (or timeout)

searx/engines/__init__.py

         'result_count': 0,
         'search_count': 0,
         'page_load_time': 0,
+        'page_load_count': 0,
+        'engine_time': 0,
+        'engine_time_count': 0,
         'score_count': 0,
         'errors': 0
     }
     return engine
 
 
+def to_percentage(stats, maxvalue):
+    for engine_stat in stats:
+        if maxvalue:
+            engine_stat['percentage'] = int(engine_stat['avg'] / maxvalue * 100)
+        else:
+            engine_stat['percentage'] = 0
+    return stats
+
+
 def get_engines_stats():
     # TODO refactor
     pageloads = []
+    engine_times = []
     results = []
     scores = []
     errors = []
     scores_per_result = []
 
-    max_pageload = max_results = max_score = max_errors = max_score_per_result = 0  # noqa
+    max_pageload = max_engine_times = max_results = max_score = max_errors = max_score_per_result = 0  # noqa
     for engine in engines.values():
         if engine.stats['search_count'] == 0:
             continue
         results_num = \
             engine.stats['result_count'] / float(engine.stats['search_count'])
-        load_times = engine.stats['page_load_time'] / float(engine.stats['search_count'])  # noqa
+
+        if engine.stats['page_load_count'] != 0:
+            load_times = engine.stats['page_load_time'] / float(engine.stats['page_load_count'])  # noqa
+        else:
+            load_times = 0
+
+        if engine.stats['engine_time_count'] != 0:
+            this_engine_time = engine.stats['engine_time'] / float(engine.stats['engine_time_count'])  # noqa
+        else:
+            this_engine_time = 0
+
         if results_num:
             score = engine.stats['score_count'] / float(engine.stats['search_count'])  # noqa
             score_per_result = score / results_num
         else:
             score = score_per_result = 0.0
-        max_results = max(results_num, max_results)
+
         max_pageload = max(load_times, max_pageload)
+        max_engine_times = max(this_engine_time, max_engine_times)
+        max_results = max(results_num, max_results)
         max_score = max(score, max_score)
         max_score_per_result = max(score_per_result, max_score_per_result)
         max_errors = max(max_errors, engine.stats['errors'])
+
         pageloads.append({'avg': load_times, 'name': engine.name})
+        engine_times.append({'avg': this_engine_time, 'name': engine.name})
         results.append({'avg': results_num, 'name': engine.name})
         scores.append({'avg': score, 'name': engine.name})
         errors.append({'avg': engine.stats['errors'], 'name': engine.name})
             'name': engine.name
         })
 
-    for engine in pageloads:
-        if max_pageload:
-            engine['percentage'] = int(engine['avg'] / max_pageload * 100)
-        else:
-            engine['percentage'] = 0
-
-    for engine in results:
-        if max_results:
-            engine['percentage'] = int(engine['avg'] / max_results * 100)
-        else:
-            engine['percentage'] = 0
-
-    for engine in scores:
-        if max_score:
-            engine['percentage'] = int(engine['avg'] / max_score * 100)
-        else:
-            engine['percentage'] = 0
-
-    for engine in scores_per_result:
-        if max_score_per_result:
-            engine['percentage'] = int(engine['avg']
-                                       / max_score_per_result * 100)
-        else:
-            engine['percentage'] = 0
-
-    for engine in errors:
-        if max_errors:
-            engine['percentage'] = int(float(engine['avg']) / max_errors * 100)
-        else:
-            engine['percentage'] = 0
+    pageloads = to_percentage(pageloads, max_pageload)
+    engine_times = to_percentage(engine_times, max_engine_times)
+    results = to_percentage(results, max_results)
+    scores = to_percentage(scores, max_score)
+    scores_per_result = to_percentage(scores_per_result, max_score_per_result)
+    erros = to_percentage(errors, max_errors)
 
     return [
         (
+            gettext('Engine time (sec)'),
+            sorted(engine_times, key=itemgetter('avg'))
+        ),
+        (
             gettext('Page loads (sec)'),
             sorted(pageloads, key=itemgetter('avg'))
         ),

searx/search.py

 number_of_searches = 0
 
 
-def search_request_wrapper(fn, url, engine_name, **kwargs):
-    ret = None
-    engine = engines[engine_name]
+def send_http_request(engine, request_params, timeout_limit):
+    response = None
     try:
-        ret = fn(url, **kwargs)
+        # create dictionary which contain all
+        # informations about the request
+        request_args = dict(
+            headers=request_params['headers'],
+            cookies=request_params['cookies'],
+            timeout=timeout_limit,
+            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']
+
+        # for page_load_time stats
+        time_before_request = time()
+
+        # send the request
+        response = req(request_params['url'], **request_args)
+
         with threading.RLock():
+            # no error : reset the suspend variables
             engine.continuous_errors = 0
             engine.suspend_end_time = 0
+            # update stats with current page-load-time
+            # only the HTTP request
+            engine.stats['page_load_time'] += time() - time_before_request
+            engine.stats['page_load_count'] += 1
+
+        # is there a timeout (no parsing in this case)
+        timeout_overhead = 0.2  # seconds
+        search_duration = time() - request_params['started']
+        if search_duration > timeout_limit + timeout_overhead:
+            logger.exception('engine timeout on HTTP request:'
+                             '{0} (search duration : {1} ms, time-out: {2} )'
+                             .format(engine.name, search_duration, timeout_limit))
+            with threading.RLock():
+                engine.stats['errors'] += 1
+            return False
+
+        # everything is ok : return the response
+        return response
+
     except:
         # increase errors stats
         with threading.RLock():
             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
+        logger.exception('engine crash: {0}'.format(engine.name))
+        return False
+
+
+def search_one_request(engine_name, query, request_params, result_container, timeout_limit):
+    engine = engines[engine_name]
+
+    # update request parameters dependent on
+    # search-engine (contained in engines folder)
+    engine.request(query, request_params)
+
+    # TODO add support of offline engines
+    if request_params['url'] is None:
+        return False
+
+    # ignoring empty urls
+    if not request_params['url']:
+        return False
+
+    # send request
+    response = send_http_request(engine, request_params, timeout_limit)
+
+    # parse response
+    success = None
+    if response:
+        # parse the response
+        response.search_params = request_params
+        search_results = engine.response(response)
+
+        # add results
+        for result in search_results:
+            result['engine'] = engine.name
+
+        result_container.extend(engine.name, search_results)
+
+        success = True
+    else:
+        success = False
 
+    with threading.RLock():
+        # update stats : total time
+        engine.stats['engine_time'] += time() - request_params['started']
+        engine.stats['engine_time_count'] += 1
 
-def threaded_requests(requests):
-    timeout_limit = max(r[2]['timeout'] for r in requests)
-    search_start = time()
+    #
+    return success
+
+
+def search_multiple_requests(requests, result_container, timeout_limit):
+    start_time = time()
     search_id = uuid4().__str__()
-    for fn, url, request_args, engine_name in requests:
-        request_args['timeout'] = timeout_limit
+
+    for engine_name, query, request_params in requests:
         th = threading.Thread(
-            target=search_request_wrapper,
-            args=(fn, url, engine_name),
-            kwargs=request_args,
+            target=search_one_request,
+            args=(engine_name, query, request_params, result_container, timeout_limit),
             name=search_id,
         )
         th._engine_name = engine_name
 
     for th in threading.enumerate():
         if th.name == search_id:
-            remaining_time = max(0.0, timeout_limit - (time() - search_start))
+            remaining_time = max(0.0, timeout_limit - (time() - start_time))
             th.join(remaining_time)
             if th.isAlive():
                 logger.warning('engine timeout: {0}'.format(th._engine_name))
     }
 
 
-# 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 = []
     def search(self):
         global number_of_searches
 
+        # start time
+        start_time = time()
+
         # init vars
         requests = []
 
 
         search_query = self.search_query
 
+        # max of all selected engine timeout
+        timeout_limit = 0
+
         # start search-reqest for all selected engines
         for selected_engine in search_query.engines:
             if selected_engine['name'] not in engines:
             request_params = default_request_params()
             request_params['headers']['User-Agent'] = user_agent
             request_params['category'] = selected_engine['category']
-            request_params['started'] = time()
+            request_params['started'] = start_time
             request_params['pageno'] = search_query.pageno
 
             if hasattr(engine, 'language') and engine.language:
             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']
+            # append request to list
+            requests.append((selected_engine['name'], search_query.query.encode('utf-8'), request_params))
 
-            # ignoring empty urls
-            if not request_params['url']:
-                continue
+            # update timeout_limit
+            timeout_limit = max(timeout_limit, engine.timeout)
 
-            # 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())
+        if requests:
+            # send all search-request
+            search_multiple_requests(requests, self.result_container, timeout_limit - (time() - start_time))
+            start_new_thread(gc.collect, tuple())
 
         # return results, suggestions, answers and infoboxes
         return self.result_container

searx/webapp.py

             if e.timeout > settings['outgoing']['request_timeout']:
                 stats[e.name]['warn_timeout'] = True
 
+    # get first element [0], the engine time,
+    # and then the second element [1] : the time (the first one is the label)
     for engine_stat in get_engines_stats()[0][1]:
         stats[engine_stat.get('name')]['time'] = round(engine_stat.get('avg'), 3)
         if engine_stat.get('avg') > settings['outgoing']['request_timeout']: