Pick pass cookies from searxng (#3252)

* [enh] Allow passing headers/cookies from settings.yml

Example:

   - engine: xpath
   - search_url: example.org
   - headers: {'example_header': 'example_header'}
   - cookies: {'safesearch': 'off'}

* [fix[ Update only cookies/headers

* [enh] XPath engine - add time range support

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

* [enh] XPath engine - add time safe-search support

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

Co-authored-by: Allen <64094914+allendema@users.noreply.github.com>
Co-authored-by: Markus Heiser <markus.heiser@darmarit.de>

searx/engines/xpath.py

@@ -5,6 +5,7 @@ from urllib.parse import urlencode
 from searx.utils import extract_text, extract_url, eval_xpath, eval_xpath_list
 
 search_url = None
+lang_all = 'en'
 url_xpath = None
 content_xpath = None
 title_xpath = None
@@ -16,15 +17,71 @@ cached_xpath = ''
 cached_url = ''
 soft_max_redirects = 0
 
-# 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)
+cookies = {}
+headers = {}
+'''Some engines might offer different result based on cookies or headers.
+Possible use-case: To set safesearch cookie or header to moderate.'''
+
+paging = False
+'''Engine supports paging [True or False].'''
+
 page_size = 1
 # number of the first page (usually 0 or 1)
 first_page_num = 1
 
 
+time_range_support = False
+'''Engine supports search time range.'''
+
+time_range_url = '&hours={time_range_val}'
+'''Time range URL parameter in the in :py:obj:`search_url`.  If no time range is
+requested by the user, the URL paramter is an empty string.  The
+``{time_range_val}`` replacement is taken from the :py:obj:`time_range_map`.
+
+.. code:: yaml
+
+    time_range_url : '&days={time_range_val}'
+'''
+
+time_range_map = {
+    'day': 24,
+    'week': 24 * 7,
+    'month': 24 * 30,
+    'year': 24 * 365,
+}
+'''Maps time range value from user to ``{time_range_val}`` in
+:py:obj:`time_range_url`.
+
+.. code:: yaml
+
+    time_range_map:
+      day: 1
+      week: 7
+      month: 30
+      year: 365
+'''
+
+safe_search_support = False
+'''Engine supports safe-search.'''
+
+safe_search_map = {
+    0: '&filter=none',
+    1: '&filter=moderate',
+    2: '&filter=strict'
+}
+'''Maps safe-search value to ``{safe_search}`` in :py:obj:`search_url`.
+
+.. code:: yaml
+
+    safesearch: true
+    safes_search_map:
+      0: '&filter=none'
+      1: '&filter=moderate'
+      2: '&filter=strict'
+
+'''
+
+
 def request(query, params):
     query = urlencode({'q': query})[2:]
 
@@ -32,8 +89,35 @@ def request(query, params):
     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
+    safe_search = ''
+    if params['safesearch']:
+        safe_search = safe_search_map[params['safesearch']]
+
+    lang = lang_all
+    if params['language'] != 'all':
+        lang = params['language'][:2]
+
+    time_range = ''
+    if params.get('time_range'):
+        time_range_val = time_range_map.get(params.get('time_range'))
+        time_range = time_range_url.format(time_range_val=time_range_val)
+
+    safe_search = ''
+    if params['safesearch']:
+        safe_search = safe_search_map[params['safesearch']]
+
+    fargs = {
+        'query': urlencode({'q': query})[2:],
+        'lang': lang,
+        'pageno': (params['pageno'] - 1) * page_size + first_page_num,
+        'time_range': time_range,
+        'safe_search': safe_search,
+    }
+
+    params['cookies'].update(cookies)
+    params['headers'].update(headers)
+
+    params['url'] = search_url.format(**fargs)
     params['soft_max_redirects'] = soft_max_redirects
 
     return params