[enh] Add engine for discourse forums

3 files changed, 164 insertions, 0 deletions

diff --git a/docs/dev/engines/online/discourse.rst b/docs/dev/engines/online/discourse.rst
new file mode 100644
index 000000000..1fab9e34c
--- /dev/null
+++ b/docs/dev/engines/online/discourse.rst
@@ -0,0 +1,8 @@
+.. _discourse engine:
+
+================
+Discourse Forums
+================
+
+.. automodule:: searx.engines.discourse
+   :members:
diff --git a/searx/engines/discourse.py b/searx/engines/discourse.py
new file mode 100644
index 000000000..298dd7ccf
--- /dev/null
+++ b/searx/engines/discourse.py
@@ -0,0 +1,153 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+""".. sidebar:: info
+
+  - `builtwith.com Discourse <https://trends.builtwith.com/websitelist/Discourse>`_
+
+Discourse is an open source Internet forum system.  To search in a forum this
+engine offers some additional settings:
+
+- :py:obj:`base_url`
+- :py:obj:`api_order`
+- :py:obj:`search_endpoint`
+- :py:obj:`show_avatar`
+
+Example
+=======
+
+To search in your favorite Discourse forum, add a configuration like shown here
+for the ``paddling.com`` forum:
+
+.. code:: yaml
+
+   - name: paddling
+     engine: discourse
+     shortcut: paddle
+     base_url: 'https://forums.paddling.com/'
+     api_order: views
+     categories: ['social media', 'sports']
+     show_avatar: true
+
+
+Implementations
+===============
+
+"""
+
+from urllib.parse import urlencode
+from datetime import datetime, timedelta
+import html
+
+from dateutil import parser
+
+from flask_babel import gettext
+
+about = {
+    "website": "https://discourse.org/",
+    "wikidata_id": "Q15054354",
+    "official_api_documentation": "https://docs.discourse.org/",
+    "use_official_api": True,
+    "require_api_key": False,
+    "results": "JSON",
+}
+
+base_url: str = None  # type: ignore
+"""URL of the Discourse forum."""
+
+search_endpoint = '/search.json'
+"""URL path of the `search endpoint`_.
+
+.. _search endpoint: https://docs.discourse.org/#tag/Search
+"""
+
+api_order = 'likes'
+"""Order method, valid values are: ``latest``, ``likes``, ``views``, ``latest_topic``"""
+
+show_avatar = False
+"""Show avatar of the user who send the post."""
+
+paging = True
+time_range_support = True
+
+AGO_TIMEDELTA = {
+    'day': timedelta(days=1),
+    'week': timedelta(days=7),
+    'month': timedelta(days=31),
+    'year': timedelta(days=365),
+}
+
+
+def request(query, params):
+
+    if len(query) <= 2:
+        return None
+
+    q = [query, f'order:{api_order}']
+    time_range = params.get('time_range')
+    if time_range:
+        after_date = datetime.now() - AGO_TIMEDELTA[time_range]
+        q.append('after:' + after_date.strftime('%Y-%m-%d'))
+
+    args = {
+        'q': ' '.join(q),
+        'page': params['pageno'],
+    }
+
+    params['url'] = f'{base_url}{search_endpoint}?{urlencode(args)}'
+    params['headers'] = {
+        'Accept': 'application/json, text/javascript, */*; q=0.01',
+        'X-Requested-With': 'XMLHttpRequest',
+    }
+
+    return params
+
+
+def response(resp):
+
+    results = []
+    json_data = resp.json()
+
+    if ('topics' or 'posts') not in json_data.keys():
+        return []
+
+    topics = {}
+
+    for item in json_data['topics']:
+        topics[item['id']] = item
+
+    for post in json_data['posts']:
+        result = topics.get(post['topic_id'], {})
+
+        url = f"{base_url}/p/{post['id']}"
+        status = gettext("closed") if result.get('closed', '') else gettext("open")
+        comments = result.get('posts_count', 0)
+        publishedDate = parser.parse(result['created_at'])
+
+        metadata = []
+        metadata.append('@' + post.get('username', ''))
+
+        if int(comments) > 1:
+            metadata.append(f'{gettext("comments")}: {comments}')
+
+        if result.get('has_accepted_answer'):
+            metadata.append(gettext("answered"))
+        elif int(comments) > 1:
+            metadata.append(status)
+
+        result = {
+            'url': url,
+            'title': html.unescape(result['title']),
+            'content': html.unescape(post.get('blurb', '')),
+            'metadata': ' | '.join(metadata),
+            'publishedDate': publishedDate,
+            'upstream': {'topics': result},
+        }
+
+        avatar = post.get('avatar_template', '').replace('{size}', '96')
+        if show_avatar and avatar:
+            result['thumbnail'] = base_url + avatar
+
+        results.append(result)
+
+    results.append({'number_of_results': len(json_data['topics'])})
+
+    return results
diff --git a/searx/searxng.msg b/searx/searxng.msg
index 17c38d3ae..013be2aff 100644
--- a/searx/searxng.msg
+++ b/searx/searxng.msg
@@ -94,4 +94,7 @@ SOCIAL_MEDIA_TERMS = {
     'POINTS': 'points',
     'TITLE': 'title',
     'AUTHOR': 'author',
+    'THREAD OPEN': 'open',
+    'THREAD CLOSED': 'closed',
+    'THREAD ANSWERED': 'answered',
 }