[mod] engines - add Stack Exchange API v2.3

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

searx/engines/stackexchange.py

@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+# lint: pylint
+"""Stack Exchange API v2.3
+
+* https://api.stackexchange.com/
+
+"""
+
+from json import loads
+from urllib.parse import urlencode
+
+about = {
+    "website": 'https://stackexchange.com',
+    "wikidata_id": 'Q3495447',
+    "official_api_documentation": 'https://api.stackexchange.com/docs',
+    "use_official_api": True,
+    "require_api_key": False,
+    "results": 'JSON',
+}
+
+paging = True
+pagesize = 10
+
+api_site = 'stackoverflow'
+api_sort= 'activity'
+api_order = 'desc'
+
+# https://api.stackexchange.com/docs/advanced-search
+search_api = 'https://api.stackexchange.com/2.3/search/advanced?'
+
+def request(query, params):
+
+    args = urlencode({
+        'q' : query,
+        'page' : params['pageno'],
+        'pagesize' : pagesize,
+        'site' : api_site,
+        'sort' : api_sort,
+        'order': 'desc',
+        })
+    params['url'] = search_api + args
+
+    return params
+
+def response(resp):
+
+    results = []
+    json_data = loads(resp.text)
+
+    for result in json_data['items']:
+
+        content = "[%s]" % ", ".join(result['tags'])
+        content += " %s" % result['owner']['display_name']
+        if result['is_answered']:
+            content += ' // is answered'
+        content += " // score: %s" % result['score']
+
+        results.append({
+            'url': "https://%s.com/q/%s" % (api_site, result['question_id']),
+            'title': result['title'],
+            'content': content,
+        })
+
+    return results