Merge pull request #333 from dalf/enh-engine-descriptions

RFC: /preferences: display engine descriptions

searx/data/__init__.py

@@ -14,6 +14,7 @@ __all__ = [
     'WIKIDATA_UNITS',
     'EXTERNAL_BANGS',
     'OSM_KEYS_TAGS',
+    'ENGINE_DESCRIPTIONS',
     'ahmia_blacklist_loader',
 ]
 
@@ -45,3 +46,4 @@ EXTERNAL_URLS = _load('external_urls.json')
 WIKIDATA_UNITS = _load('wikidata_units.json')
 EXTERNAL_BANGS = _load('external_bangs.json')
 OSM_KEYS_TAGS = _load('osm_keys_tags.json')
+ENGINE_DESCRIPTIONS = _load('engine_descriptions.json')

searx/engines/bandcamp.py

@@ -12,6 +12,16 @@ from dateutil.parser import parse as dateparse
 from lxml import html
 from searx.utils import extract_text
 
+# about
+about = {
+    "website": 'https://bandcamp.com/',
+    "wikidata_id": 'Q545966',
+    "official_api_documentation": 'https://bandcamp.com/developer',
+    "use_official_api": False,
+    "require_api_key": False,
+    "results": 'HTML',
+}
+
 categories = ['music']
 paging = True
 

searx/engines/photon.py

@@ -9,9 +9,9 @@ from searx.utils import searx_useragent
 
 # about
 about = {
-    "website": 'https://photon.komoot.de',
+    "website": 'https://photon.komoot.io',
     "wikidata_id": None,
-    "official_api_documentation": 'https://photon.komoot.de/',
+    "official_api_documentation": 'https://photon.komoot.io/',
     "use_official_api": True,
     "require_api_key": False,
     "results": 'JSON',

searx/settings.yml

@@ -1618,7 +1618,7 @@ engines:
     categories: general
     about:
       website: https://brave.com/search/
-      wikidata_id: Q22906900
+      wikidata_id: Q107355971
       use_official_api: false
       require_api_key: false
       results: HTML

searx/static/themes/oscar/css/logicodev-dark.css

@@ -1309,6 +1309,7 @@ input.cursor-text {
   font-size: 14px;
   font-weight: normal;
   z-index: 1000000;
+  max-width: 40rem;
 }
 td:hover .engine-tooltip,
 th:hover .engine-tooltip,

searx/static/themes/oscar/css/logicodev.css

@@ -1336,6 +1336,7 @@ input.cursor-text {
   font-size: 14px;
   font-weight: normal;
   z-index: 1000000;
+  max-width: 40rem;
 }
 td:hover .engine-tooltip,
 th:hover .engine-tooltip,

searx/static/themes/oscar/js/searx.js

@@ -299,6 +299,29 @@ $(document).ready(function(){
         $( this ).off( event );
     });
 });
+;$(document).ready(function(){
+    let engine_descriptions = null;
+    function load_engine_descriptions() {
+        if (engine_descriptions == null) {
+            $.ajax("engine_descriptions.json", dataType="json").done(function(data) {
+                engine_descriptions = data;
+                for (const [engine_name, description] of Object.entries(data)) {
+                    let elements = $('[data-engine-name="' + engine_name + '"] .description');
+                    for(const element of elements) {
+                        let source = ' (<i>' + searx.translations['Source'] + ':&nbsp;' + description[1] + '</i>)';
+                        element.innerHTML = description[0] + source;
+                    }
+                }
+            });
+        }
+    }
+
+    if (document.querySelector('body[class="preferences_endpoint"]')) {
+        $('[data-engine-name]').hover(function() {
+            load_engine_descriptions();
+        });
+    }
+});
 ;$(document).ready(function(){
     $("#allow-all-engines").click(function() {
         $(".onoffswitch-checkbox").each(function() { this.checked = false;});

searx/static/themes/oscar/src/js/preferences.js

@@ -0,0 +1,23 @@
+$(document).ready(function(){
+    let engine_descriptions = null;
+    function load_engine_descriptions() {
+        if (engine_descriptions == null) {
+            $.ajax("engine_descriptions.json", dataType="json").done(function(data) {
+                engine_descriptions = data;
+                for (const [engine_name, description] of Object.entries(data)) {
+                    let elements = $('[data-engine-name="' + engine_name + '"] .description');
+                    for(const element of elements) {
+                        let source = ' (<i>' + searx.translations['Source'] + ':&nbsp;' + description[1] + '</i>)';
+                        element.innerHTML = description[0] + source;
+                    }
+                }
+            });
+        }
+    }
+
+    if (document.querySelector('body[class="preferences_endpoint"]')) {
+        $('[data-engine-name]').hover(function() {
+            load_engine_descriptions();
+        });
+    }
+});

searx/static/themes/oscar/src/less/logicodev/preferences.less

@@ -25,6 +25,7 @@ input.cursor-text {
     font-size: 14px;
     font-weight: normal;
     z-index: 1000000; 
+    max-width: 40rem;
 }
 
 td:hover .engine-tooltip, th:hover .engine-tooltip, .engine-tooltip:hover {

searx/static/themes/simple/css/searx-rtl.css

@@ -1929,6 +1929,14 @@ td:hover .engine-tooltip,
 #main_preferences div.selectable_url pre {
   width: 100%;
 }
+#main_preferences th.name .engine-tooltip {
+  margin-top: 1.8rem;
+  left: 20rem;
+  max-width: 40rem;
+}
+#main_preferences th.name .engine-tooltip .engine-description {
+  margin-top: 0.5rem;
+}
 @media screen and (max-width: 75em) {
   .preferences_back {
     clear: both;

searx/static/themes/simple/css/searx.css

@@ -1929,6 +1929,14 @@ td:hover .engine-tooltip,
 #main_preferences div.selectable_url pre {
   width: 100%;
 }
+#main_preferences th.name .engine-tooltip {
+  margin-top: 1.8rem;
+  left: 20rem;
+  max-width: 40rem;
+}
+#main_preferences th.name .engine-tooltip .engine-description {
+  margin-top: 0.5rem;
+}
 @media screen and (max-width: 75em) {
   .preferences_back {
     clear: both;

searx/static/themes/simple/js/searx.js

@@ -621,6 +621,33 @@ searx.ready(function() {
     });
   });
 })(window, document, window.searx);
+;(function (w, d, searx) {
+    'use strict';
+
+    searx.ready(function() {
+        let engine_descriptions = null;
+        function load_engine_descriptions() {
+            if (engine_descriptions == null) {
+                searx.http("GET", "engine_descriptions.json").then(function(content) {
+                    engine_descriptions = JSON.parse(content);
+                    for (const [engine_name, description] of Object.entries(engine_descriptions)) {
+                        let elements = d.querySelectorAll('[data-engine-name="' + engine_name + '"] .engine-description');
+                        for(const element of elements) {
+                            let source = ' (<i>' + searx.translations['Source'] + ':&nbsp;' + description[1] + '</i>)';
+                            element.innerHTML = description[0] + source;
+                        }
+                    }
+                });
+            }
+        }
+
+        if (d.querySelector('body[class="preferences_endpoint"]')) {
+            for(const el of d.querySelectorAll('[data-engine-name]')) {
+                searx.on(el, 'mouseenter', load_engine_descriptions);
+            }
+        }
+    });
+})(window, document, window.searx);
 ;/**
 * searx is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by

searx/static/themes/simple/src/js/main/searx_preferences.js

@@ -0,0 +1,27 @@
+(function (w, d, searx) {
+    'use strict';
+
+    searx.ready(function() {
+        let engine_descriptions = null;
+        function load_engine_descriptions() {
+            if (engine_descriptions == null) {
+                searx.http("GET", "engine_descriptions.json").then(function(content) {
+                    engine_descriptions = JSON.parse(content);
+                    for (const [engine_name, description] of Object.entries(engine_descriptions)) {
+                        let elements = d.querySelectorAll('[data-engine-name="' + engine_name + '"] .engine-description');
+                        for(const element of elements) {
+                            let source = ' (<i>' + searx.translations['Source'] + ':&nbsp;' + description[1] + '</i>)';
+                            element.innerHTML = description[0] + source;
+                        }
+                    }
+                });
+            }
+        }
+
+        if (d.querySelector('body[class="preferences_endpoint"]')) {
+            for(const el of d.querySelectorAll('[data-engine-name]')) {
+                searx.on(el, 'mouseenter', load_engine_descriptions);
+            }
+        }
+    });
+})(window, document, window.searx);

searx/static/themes/simple/src/less/preferences.less

@@ -108,6 +108,18 @@
       width: 100%;
     }
   }
+
+  th.name {
+    .engine-tooltip {
+      margin-top: 1.8rem;
+      left: 20rem;
+      max-width: 40rem;
+
+      .engine-description {
+        margin-top: 0.5rem;
+      }
+    }
+  }
 }
 
 @media screen and (max-width: 75em) {

searx/templates/oscar/preferences.html

@@ -4,6 +4,7 @@
 {% if search_engine.about is defined or stats[search_engine.name]['result_count'] > 0 %}
 {% set about = search_engine.about %}
 <div class="engine-tooltip" role="tooltip" id="{{ id }}">{{- "" -}}
+    <p class="description"></p>
     {% if search_engine.about is defined %}
         <h5><a href="{{about.website}}" rel="noreferrer">{{about.website}}</a></h5>
         {%- if about.wikidata_id -%}<p><a href="https://www.wikidata.org/wiki/{{about.wikidata_id}}" rel="noreferrer">wikidata.org/wiki/{{about.wikidata_id}}</a></p>{%- endif -%}
@@ -343,7 +344,7 @@
                                         <td class="onoff-checkbox">
                                         {{- checkbox_toggle('engine_' + search_engine.name|replace(' ', '_') + '__' + categ|replace(' ', '_'), (search_engine.name, categ) in disabled_engines) -}}
                                         </td>
-                                        <th scope="row"><span aria-labelledby="{{ 'tooltip_' + categ + '_' + search_engine.name }}">
+                                        <th scope="row" data-engine-name="{{ search_engine.name }}"><span aria-labelledby="{{ 'tooltip_' + categ + '_' + search_engine.name }}">
                                             {%- if search_engine.enable_http %}{{ icon('exclamation-sign', 'No HTTPS') }}{% endif -%}
                                             {{- search_engine.name -}}</span>
                                             {{- engine_about(search_engine, 'tooltip_' + categ + '_' + search_engine.name) -}}
@@ -363,7 +364,7 @@
                                         <td>{{ support_toggle(supports[search_engine.name]['safesearch']) }}</td>
                                         <td>{{ support_toggle(supports[search_engine.name]['supports_selected_language']) }}</td>
                                         <td>{{ shortcuts[search_engine.name] }}</td>
-                                        <th scope="row"><span>{% if search_engine.enable_http %}{{ icon('exclamation-sign', 'No HTTPS') }}{% endif %}{{ search_engine.name }}</span>{{ engine_about(search_engine) }}</th>
+                                        <th scope="row" data-engine-name="{{ search_engine.name }}"><span>{% if search_engine.enable_http %}{{ icon('exclamation-sign', 'No HTTPS') }}{% endif %}{{ search_engine.name }}</span>{{ engine_about(search_engine) }}</th>
                                         <td class="onoff-checkbox">
                                         {{ checkbox_toggle('engine_' + search_engine.name|replace(' ', '_') + '__' + categ|replace(' ', '_'), (search_engine.name, categ) in disabled_engines) }}
                                         </td>

searx/templates/simple/preferences.html

@@ -22,6 +22,7 @@
 {% if search_engine.about is defined %}
 {% set about = search_engine.about %}
 <div class="engine-tooltip" role="tooltip">{{- "" -}}
+    <p class="engine-description"></p>
     <p><a href="{{about.website}}" rel="noreferrer">{{about.website}}</a></p>
     {%- if about.wikidata_id -%}<p><a href="https://www.wikidata.org/wiki/{{about.wikidata_id}}" rel="noreferrer">wikidata.org/wiki/{{about.wikidata_id}}</a></p>{%- endif -%}
     {%- if search_engine.enable_http %}<p>{{ icon('exclamation-sign', 'No HTTPS') }}{{ _('No HTTPS')}}</p>{% endif -%}
@@ -262,7 +263,7 @@
       {% set engine_id = 'engine_' + search_engine.name|replace(' ', '_') + '__' + categ|replace(' ', '_') %}
       <tr>
         <td class="engine_checkbox">{{ checkbox_onoff(engine_id, (search_engine.name, categ) in disabled_engines) }}</td>
-        <th class="name">{% if search_engine.enable_http %}{{ icon('warning', 'No HTTPS') }}{% endif %} {{ search_engine.name }} {{ engine_about(search_engine) }}</th>
+        <th class="name" data-engine-name="{{ search_engine.name }}">{% if search_engine.enable_http %}{{ icon('warning', 'No HTTPS') }}{% endif %} {{ search_engine.name }} {{ engine_about(search_engine) }}</th>
         <td class="shortcut">{{ shortcuts[search_engine.name] }}</td>
         <td>{{ checkbox(engine_id + '_supported_languages', supports[search_engine.name]['supports_selected_language'], true, true) }}</td>
         <td>{{ checkbox(engine_id + '_safesearch', supports[search_engine.name]['safesearch'], true, true) }}</td>

searx/webapp.py

@@ -54,6 +54,7 @@ from searx import (
     settings,
     searx_debug,
 )
+from searx.data import ENGINE_DESCRIPTIONS
 from searx.settings_defaults import OUTPUT_FORMATS
 from searx.settings_loader import get_default_settings_path
 from searx.exceptions import SearxParameterException
@@ -393,7 +394,9 @@ def image_proxify(url):
 def get_translations():
     return {
         # when there is autocompletion
-        'no_item_found': gettext('No item found')
+        'no_item_found': gettext('No item found'),
+        # /preferences: the source of the engine description (wikipedata, wikidata, website)
+        'Source': gettext('Source'),
     }
 
 
@@ -1140,6 +1143,23 @@ def image_proxy():
         return '', 400
 
 
+@app.route('/engine_descriptions.json', methods=['GET'])
+def engine_descriptions():
+    locale = get_locale().split('_')[0]
+    result = ENGINE_DESCRIPTIONS['en'].copy()
+    if locale != 'en':
+        for engine, description in ENGINE_DESCRIPTIONS.get(locale, {}).items():
+            result[engine] = description
+    for engine, description in result.items():
+        if len(description) ==2 and description[1] == 'ref':
+            ref_engine, ref_lang = description[0].split(':')
+            description = ENGINE_DESCRIPTIONS[ref_lang][ref_engine]
+        if isinstance(description, str):
+            description = [ description, 'wikipedia' ]
+        result[engine] = description
+    return jsonify(result)
+
+
 @app.route('/stats', methods=['GET'])
 def stats():
     """Render engine statistics page."""

searx_extra/update/update_engine_descriptions.py

@@ -1,15 +1,19 @@
 #!/usr/bin/env python
 
-import sys
 import json
-from urllib.parse import quote, urlparse
-import detect_language
+from urllib.parse import urlparse
+from os.path import join
+
 from lxml.html import fromstring
 
+from langdetect import detect_langs
+from langdetect.lang_detect_exception import LangDetectException
+
 from searx.engines import wikidata, set_loggers
-from searx.utils import extract_text
+from searx.utils import extract_text, match_language
 from searx.locales import LOCALE_NAMES
-import searx
+from searx import searx_dir
+from searx.utils import gen_useragent
 import searx.search
 import searx.network
 
@@ -18,6 +22,7 @@ set_loggers(wikidata, 'wikidata')
 SPARQL_WIKIPEDIA_ARTICLE = """
 SELECT DISTINCT ?item ?name
 WHERE {
+  hint:Query hint:optimizer "None".
   VALUES ?item { %IDS% }
   ?article schema:about ?item ;
               schema:inLanguage ?lang ;
@@ -38,8 +43,23 @@ WHERE {
 ORDER BY ?itemLang
 """
 
+NOT_A_DESCRIPTION = [
+    'web site',
+    'site web',
+    'komputa serĉilo',
+    'interreta serĉilo',
+    'bilaketa motor',
+    'web search engine',
+    'wikimedia täpsustuslehekülg',
+]
+
+SKIP_ENGINE_SOURCE = [
+    ('gitlab', 'wikidata')  # descriptions are about wikipedia disambiguation pages
+]
+
 LANGUAGES = LOCALE_NAMES.keys()
-LANGUAGES_SPARQL = ', '.join(set(map(lambda l: repr(l.split('_')[0]), LANGUAGES)))
+WIKIPEDIA_LANGUAGES = {'language': 'wikipedia_language'}
+LANGUAGES_SPARQL = ''
 IDS = None
 
 descriptions = {}
@@ -54,15 +74,30 @@ def normalize_description(description):
 
 
 def update_description(engine_name, lang, description, source, replace=True):
+    if not isinstance(description, str):
+        return
+    description = normalize_description(description)
+    if description.lower() == engine_name.lower():
+        return
+    if description.lower() in NOT_A_DESCRIPTION:
+        return
+    if (engine_name, source) in SKIP_ENGINE_SOURCE:
+        return
+    if ' ' not in description:
+        # skip unique word description (like "website")
+        return
     if replace or lang not in descriptions[engine_name]:
-        descriptions[engine_name][lang] = [normalize_description(description), source]
+        descriptions[engine_name][lang] = [description, source]
 
 
-def get_wikipedia_summary(language, pageid):
-    search_url = 'https://{language}.wikipedia.org/api/rest_v1/page/summary/{title}'
-    url = search_url.format(title=quote(pageid), language=language)
+def get_wikipedia_summary(lang, pageid):
+    params = {
+        'language': lang.replace('_','-'),
+        'headers': {}
+    }
+    searx.engines.engines['wikipedia'].request(pageid, params)
     try:
-        response = searx.network.get(url)
+        response = searx.network.get(params['url'], headers=params['headers'], timeout=10)
         response.raise_for_status()
         api_result = json.loads(response.text)
         return api_result.get('extract')
@@ -71,15 +106,19 @@ def get_wikipedia_summary(language, pageid):
 
 
 def detect_language(text):
-    r = cld3.get_language(str(text))  # pylint: disable=E1101
-    if r is not None and r.probability >= 0.98 and r.is_reliable:
-        return r.language
+    try:
+        r = detect_langs(str(text))  # pylint: disable=E1101
+    except LangDetectException:
+        return None
+
+    if len(r) > 0 and r[0].prob > 0.95:
+        return r[0].lang
     return None
 
 
 def get_website_description(url, lang1, lang2=None):
     headers = {
-        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:84.0) Gecko/20100101 Firefox/84.0',
+        'User-Agent': gen_useragent(),
         'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8',
         'DNT': '1',
         'Upgrade-Insecure-Requests': '1',
@@ -117,8 +156,15 @@ def get_website_description(url, lang1, lang2=None):
 
 
 def initialize():
-    global descriptions, wd_to_engine_name, IDS
+    global IDS, WIKIPEDIA_LANGUAGES, LANGUAGES_SPARQL
     searx.search.initialize()
+    wikipedia_engine = searx.engines.engines['wikipedia']
+    WIKIPEDIA_LANGUAGES = {
+        language: wikipedia_engine.url_lang(language.replace('_', '-'))
+        for language in LANGUAGES
+    }
+    WIKIPEDIA_LANGUAGES['nb_NO'] = 'no'
+    LANGUAGES_SPARQL = ', '.join(f"'{l}'" for l in set(WIKIPEDIA_LANGUAGES.values()))
     for engine_name, engine in searx.engines.engines.items():
         descriptions[engine_name] = {}
         wikidata_id = getattr(engine, "about", {}).get('wikidata_id')
@@ -129,7 +175,7 @@ def initialize():
 
 
 def fetch_wikidata_descriptions():
-    global IDS
+    searx.network.set_timeout_for_thread(60)
     result = wikidata.send_wikidata_query(
         SPARQL_DESCRIPTION
         .replace('%IDS%', IDS)
@@ -138,15 +184,15 @@ def fetch_wikidata_descriptions():
     if result is not None:
         for binding in result['results']['bindings']:
             wikidata_id = binding['item']['value'].replace('http://www.wikidata.org/entity/', '')
-            lang = binding['itemDescription']['xml:lang']
+            wikidata_lang = binding['itemDescription']['xml:lang']
             description = binding['itemDescription']['value']
-            if ' ' in description:  # skip unique word description (like "website")
-                for engine_name in wd_to_engine_name[wikidata_id]:
-                    update_description(engine_name, lang, description, 'wikidata')
+            for engine_name in wd_to_engine_name[wikidata_id]:
+                for lang in LANGUAGES:
+                    if WIKIPEDIA_LANGUAGES[lang] == wikidata_lang:
+                        update_description(engine_name, lang, description, 'wikidata')
 
 
 def fetch_wikipedia_descriptions():
-    global IDS
     result = wikidata.send_wikidata_query(
         SPARQL_WIKIPEDIA_ARTICLE
         .replace('%IDS%', IDS)
@@ -155,12 +201,13 @@ def fetch_wikipedia_descriptions():
     if result is not None:
         for binding in result['results']['bindings']:
             wikidata_id = binding['item']['value'].replace('http://www.wikidata.org/entity/', '')
-            lang = binding['name']['xml:lang']
+            wikidata_lang = binding['name']['xml:lang']
             pageid = binding['name']['value']
-            description = get_wikipedia_summary(lang, pageid)
-            if description is not None and ' ' in description:
-                for engine_name in wd_to_engine_name[wikidata_id]:
-                    update_description(engine_name, lang, description, 'wikipedia')
+            for engine_name in wd_to_engine_name[wikidata_id]:
+                for lang in LANGUAGES:
+                    if WIKIPEDIA_LANGUAGES[lang] == wikidata_lang:
+                        description = get_wikipedia_summary(lang, pageid)
+                        update_description(engine_name, lang, description, 'wikipedia')
 
 
 def normalize_url(url):
@@ -173,36 +220,96 @@ def normalize_url(url):
 def fetch_website_description(engine_name, website):
     default_lang, default_description = get_website_description(website, None, None)
     if default_lang is None or default_description is None:
+        # the front page can't be fetched: skip this engine
         return
-    if default_lang not in descriptions[engine_name]:
-        descriptions[engine_name][default_lang] = [normalize_description(default_description), website]
-    for request_lang in ('en-US', 'es-US', 'fr-FR', 'zh', 'ja', 'ru', 'ar', 'ko'):
-        if request_lang.split('-')[0] not in descriptions[engine_name]:
-            lang, desc = get_website_description(website, request_lang, request_lang.split('-')[0])
-            if desc is not None and desc != default_description:
-                update_description(engine_name, lang, desc, website, replace=False)
+
+    wikipedia_languages_r = { V: K for K, V in WIKIPEDIA_LANGUAGES.items() }
+    languages = ['en', 'es', 'pt', 'ru', 'tr', 'fr']
+    languages = languages + [ l for l in LANGUAGES if l not in languages]
+
+    previous_matched_lang = None
+    previous_count = 0
+    for lang in languages:
+        if lang not in descriptions[engine_name]:
+            fetched_lang, desc = get_website_description(website, lang, WIKIPEDIA_LANGUAGES[lang])
+            if fetched_lang is None or desc is None:
+                continue
+            matched_lang = match_language(fetched_lang, LANGUAGES, fallback=None)
+            if matched_lang is None:
+                fetched_wikipedia_lang = match_language(fetched_lang, WIKIPEDIA_LANGUAGES.values(), fallback=None)
+                matched_lang = wikipedia_languages_r.get(fetched_wikipedia_lang)
+            if matched_lang is not None:
+                update_description(engine_name, matched_lang, desc, website, replace=False)
+            # check if desc changed with the different lang values
+            if matched_lang == previous_matched_lang:
+                previous_count += 1
+                if previous_count == 6:
+                    # the website has returned the same description for 6 different languages in Accept-Language header
+                    # stop now
+                    break
             else:
-                break
+                previous_matched_lang = matched_lang
+                previous_count = 0
 
 
 def fetch_website_descriptions():
     for engine_name, engine in searx.engines.engines.items():
         website = getattr(engine, "about", {}).get('website')
-        if website is None:
+        if website is None and hasattr(engine, "search_url"):
             website = normalize_url(getattr(engine, "search_url"))
-        if website is None:
+        if website is None and hasattr(engine, "base_url"):
             website = normalize_url(getattr(engine, "base_url"))
         if website is not None:
             fetch_website_description(engine_name, website)
 
 
+def get_engine_descriptions_filename():
+    return join(join(searx_dir, "data"), "engine_descriptions.json")
+
+
+def get_output():
+    """
+    From descriptions[engine][language] = [description, source]
+    To
+
+    * output[language][engine] = description_and_source
+    * description_and_source can be:
+       * [description, source]
+       * description (if source = "wikipedia")
+       * [f"engine:lang", "ref"] (reference to another existing description)
+    """
+    output = {
+        locale: {} for locale in LOCALE_NAMES
+    }
+
+    seen_descriptions = {}
+
+    for engine_name, lang_descriptions in descriptions.items():
+        for language, description in lang_descriptions.items():
+            if description[0] in seen_descriptions:
+                ref = seen_descriptions[description[0]]
+                description = [f'{ref[0]}:{ref[1]}', 'ref']
+            else:
+                seen_descriptions[description[0]] = (engine_name, language)
+                if description[1] == 'wikipedia':
+                    description = description[0]
+            output.setdefault(language, {}).setdefault(engine_name, description)
+
+    return output
+
+
 def main():
     initialize()
+    print('Fetching wikidata descriptions')
     fetch_wikidata_descriptions()
+    print('Fetching wikipedia descriptions')
     fetch_wikipedia_descriptions()
+    print('Fetching website descriptions')
     fetch_website_descriptions()
 
-    sys.stdout.write(json.dumps(descriptions, indent=1, separators=(',', ':'), ensure_ascii=False))
+    output = get_output()
+    with open(get_engine_descriptions_filename(), 'w', encoding='utf8') as f:
+        f.write(json.dumps(output, indent=1, separators=(',', ':'), ensure_ascii=False))
 
 
 if __name__ == "__main__":