FIX: Load complete category objects

Not all categories are preloaded when lazy_load_categories is enabled.
In this case, the category objects that are loaded through /docs.json
must be complete.

assets/javascripts/discourse/models/docs.js

@@ -1,5 +1,6 @@
 import EmberObject from "@ember/object";
 import { ajax } from "discourse/lib/ajax";
+import Site from "discourse/models/site";
 import Topic from "discourse/models/topic";
 import User from "discourse/models/user";
 import { getDocs } from "../../lib/get-docs";
@@ -38,6 +39,13 @@ Docs.reopenClass({
     }
 
     return ajax(`/${docsPath}.json?${filters.join("&")}`).then((data) => {
+      const site = Site.current();
+      if (site.lazy_load_categories) {
+        data.categories?.forEach((category) => site.updateCategory(category));
+        data.topics.topic_list.categories?.forEach((category) =>
+          site.updateCategory(category)
+        );
+      }
       data.topics.topic_list.topics = data.topics.topic_list.topics.map(
         (topic) => Topic.create(topic)
       );
@@ -51,6 +59,12 @@ Docs.reopenClass({
 
   loadMore(loadMoreUrl) {
     return ajax(loadMoreUrl).then((data) => {
+      const site = Site.current();
+      if (site.lazy_load_categories) {
+        data.topics.topic_list.categories?.forEach((category) =>
+          site.updateCategory(category)
+        );
+      }
       data.topics.topic_list.topics = data.topics.topic_list.topics.map(
         (topic) => Topic.create(topic)
       );

lib/docs/query.rb

@@ -210,12 +210,33 @@ module Docs
       tags_object.sort_by { |tag| [tag[:active] ? 0 : 1, -tag[:count]] }
     end
 
-    def create_categories_object(categories)
+    def create_categories_object(category_counts)
+      categories =
+        Category
+          .where(id: category_counts.keys)
+          .includes(
+            :uploaded_logo,
+            :uploaded_logo_dark,
+            :uploaded_background,
+            :uploaded_background_dark,
+          )
+          .joins("LEFT JOIN topics t on t.id = categories.topic_id")
+          .select("categories.*, t.slug topic_slug")
+          .index_by(&:id)
+
       categories_object = []
 
-      categories.each do |category|
-        active = @filters[:category].include?(category[0].to_s) if @filters[:category]
-        categories_object << { id: category[0], count: category[1], active: active || false }
+      category_counts.each do |id, count|
+        active = @filters[:category] && @filters[:category].include?(id.to_s)
+
+        categories_object << if @guardian.can_lazy_load_categories?
+          BasicCategorySerializer
+            .new(categories[id], scope: @guardian, root: false)
+            .as_json
+            .merge(id:, count:, active:)
+        else
+          category_object = { id:, count:, active: }
+        end
       end
 
       categories_object.sort_by { |category| [category[:active] ? 0 : 1, -category[:count]] }