[enh] Add Tineye reverse image search (#3040)

* [enh] Add Tineye reverse image search 

Other optional parametesr:

"&sort=crawl_date" can be appended to search_string to sort results by date.
"&domain=example.org" can be implemented to search_string to get results from just one domain.

Public instances could get relatively fast timed-out for 3600s.

* [enh] Add TIneye to settings.yml 

Check if that's the right shortcut.

* [mod] Fix checks

* [mod] Try to fix checks

* [mod] Use Four spaces for indentation

And set paging back to True

Co-authored-by: Noémi Ványi <kvch@users.noreply.github.com>

searx/engines/tineye.py

@@ -0,0 +1,86 @@
+"""
+Tineye - Reverse search images
+"""
+
+from json import loads
+from urllib.parse import urlencode
+
+from datetime import datetime
+
+about = {
+    "website": "https://tineye.com",
+    "wikidata_id": "Q2382535",
+    "use_official_api": False,
+    "require_api_key": False,
+    "results": "JSON",
+}
+
+
+categories = ['images']
+paging = True
+
+safesearch = False
+
+
+base_url = 'https://tineye.com'
+search_string = '/result_json/?page={page}&{query}'
+
+
+def request(query, params):
+    params['url'] = base_url +\
+        search_string.format(
+            query=urlencode({'url': query}),
+            page=params['pageno'])
+
+    params['headers'].update({
+        'Connection': 'keep-alive',
+        'Accept-Encoding': 'gzip, defalte, br',
+        'Host': 'tineye.com',
+        'DNT': '1',
+        'TE': 'trailers',
+    })
+
+    return params
+
+
+def response(resp):
+    results = []
+    # Define wanted results
+    json_data = loads(resp.text)
+    number_of_results = json_data['num_matches']
+
+    for i in json_data['matches']:
+        for i in json_data['matches']:
+            image_format = i['format']
+            width = i['width']
+            height = i['height']
+            thumbnail_src = i['image_url']
+            backlink = i['domains'][0]['backlinks'][0]
+
+            url = backlink['backlink']
+            source = backlink['url']
+            title = backlink['image_name']
+            img_src = backlink['url']
+
+            # Get and convert published date
+            api_date = backlink['crawl_date'][:-3]
+            publishedDate = datetime.fromisoformat(api_date)
+
+            # Append results
+            results.append({
+                'template': 'images.html',
+                'url': url,
+                'thumbnail_src': thumbnail_src,
+                'source': source,
+                'title': title,
+                'img_src': img_src,
+                'format': image_format,
+                'widht': width,
+                'height': height,
+                'publishedDate': publishedDate,
+            })
+
+    # Append number of results
+    results.append({'number_of_results': number_of_results})
+
+    return results

searx/settings.yml

@@ -410,6 +410,13 @@ engines:
     timeout: 3.0
     disabled : True
 
+  - name : tineye
+    engine : tineye
+    shortcut : tin
+    paging : True
+    timeout : 9.0
+    disabled : True
+
   - name : etools
     engine : etools
     shortcut : eto