[enh] introduce categories_as_tabs

Previously all categories were displayed as search engine tabs.
This commit changes that so that only the categories listed under
categories_as_tabs in settings.yml are displayed.

This lets us introduce more categories without cluttering up the UI.
Categories not displayed as tabs  can still be searched with !bangs.

3 files changed, 32 insertions, 7 deletions

diff --git a/docs/admin/engines/configured_engines.rst b/docs/admin/engines/configured_engines.rst
index 82a1d2375..c7b6a1f52 100644
--- a/docs/admin/engines/configured_engines.rst
+++ b/docs/admin/engines/configured_engines.rst
@@ -16,11 +16,18 @@ Explanation of the :ref:`general engine configuration` shown in the table
 
    SearXNG supports {{engines | length}} search engines (of which {{enabled_engine_count}} are enabled by default).
 
-   {% for category, engines in categories.items() %}
+   {% for category, engines in categories_as_tabs.items() %}
 
    {{category}} search engines
    ---------------------------------------
 
+   {% for group, engines in engines | group_engines_in_tab %}
+
+   {% if loop.length > 1 %}
+   {{group}}
+   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+   {% endif %}
+
    .. flat-table::
       :header-rows: 2
       :stub-columns: 1
@@ -39,7 +46,7 @@ Explanation of the :ref:`general engine configuration` shown in the table
         - Safe search
         - Time range
 
-      {% for mod in engines | sort_engines %}
+      {% for mod in engines %}
 
       * - `{{mod.name}} <{{mod.about and mod.about.website}}>`_
         - ``!{{mod.shortcut}}``
@@ -65,3 +72,4 @@ Explanation of the :ref:`general engine configuration` shown in the table
 
      {% endfor %}
      {% endfor %}
+     {% endfor %}
diff --git a/docs/admin/engines/settings.rst b/docs/admin/engines/settings.rst
index b04de7cb3..cf561a5ab 100644
--- a/docs/admin/engines/settings.rst
+++ b/docs/admin/engines/settings.rst
@@ -219,6 +219,26 @@ Communication with search engines.
 ``max_redirects`` :
   30 by default. Maximum redirect before it is an error.
 
+``categories_as_tabs:``
+-----------------------
+
+A list of the categories that are displayed as tabs in the user interface.
+Categories not listed here can still be searched with the :ref:`search-syntax`.
+
+.. code-block:: yaml
+
+  categories_as_tabs:
+    - general
+    - images
+    - videos
+    - news
+    - map
+    - music
+    - it
+    - science
+    - files
+    - social media
+
 .. _settings engine:
 
 Engine settings
diff --git a/docs/conf.py b/docs/conf.py
index 1b78ece60..da989e62e 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -50,14 +50,11 @@ jinja_contexts = {
         },
         'enabled_engine_count': sum(not x.disabled for x in searx.engines.engines.values()),
         'categories': searx.engines.categories,
+        'categories_as_tabs': {c: searx.engines.categories[c] for c in searx.settings['categories_as_tabs']},
     },
 }
 jinja_filters = {
-    'sort_engines':
-    lambda engines: sorted(
-        engines,
-        key=lambda engine: (engine.about.get('language', ''), engine.name)
-    )
+    'group_engines_in_tab': searx.engines.group_engines_in_tab,
 }
 
 # Let the Jinja template in configured_engines.rst access documented_modules