[mod] replace old stackoverflow engine by Stack Exchange API v2.3

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

searx/engines/stackoverflow.py

@@ -1,64 +0,0 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
-"""
- Stackoverflow (IT)
-"""
-
-from urllib.parse import urlencode, urljoin
-from lxml import html
-from searx.utils import extract_text
-from searx.exceptions import SearxEngineCaptchaException
-
-# about
-about = {
-    "website": 'https://stackoverflow.com/',
-    "wikidata_id": 'Q549037',
-    "official_api_documentation": 'https://api.stackexchange.com/docs',
-    "use_official_api": False,
-    "require_api_key": False,
-    "results": 'HTML',
-}
-
-# engine dependent config
-categories = ['it']
-paging = True
-
-# search-url
-url = 'https://stackoverflow.com/'
-search_url = url + 'search?{query}&page={pageno}'
-
-# specific xpath variables
-results_xpath = '//div[contains(@class,"question-summary")]'
-link_xpath = './/div[@class="result-link"]//a|.//div[@class="summary"]//h3//a'
-content_xpath = './/div[@class="excerpt"]'
-
-
-# do search-request
-def request(query, params):
-    params['url'] = search_url.format(query=urlencode({'q': query}), pageno=params['pageno'])
-
-    return params
-
-
-# get response from search-request
-def response(resp):
-    if resp.url.path.startswith('/nocaptcha'):
-        raise SearxEngineCaptchaException()
-
-    results = []
-
-    dom = html.fromstring(resp.text)
-
-    # parse results
-    for result in dom.xpath(results_xpath):
-        link = result.xpath(link_xpath)[0]
-        href = urljoin(url, link.attrib.get('href'))
-        title = extract_text(link)
-        content = extract_text(result.xpath(content_xpath))
-
-        # append result
-        results.append({'url': href,
-                        'title': title,
-                        'content': content})
-
-    # return results
-    return results

searx/settings.yml

@@ -1047,9 +1047,11 @@ engines:
     engine : soundcloud
     shortcut : sc
 
-  - name : stackoverflow
-    engine : stackoverflow
-    shortcut : st
+  - name: stackoverflow
+    engine: stackexchange
+    shortcut: st
+    api_site: 'stackoverflow'
+    categories: it
 
   - name : searchcode code
     engine : searchcode_code