FIX: Load categories with search topic results (discourse#25700)

Add categories to the serialized search results together with the topics
when lazy load categories is enabled. This is necessary in order for the
results to be rendered correctly and display the category information.

app/assets/javascripts/discourse/app/lib/search.js

@@ -9,6 +9,7 @@ import userSearch from "discourse/lib/user-search";
 import { escapeExpression } from "discourse/lib/utilities";
 import Category from "discourse/models/category";
 import Post from "discourse/models/post";
+import Site from "discourse/models/site";
 import Topic from "discourse/models/topic";
 import User from "discourse/models/user";
 import getURL from "discourse-common/lib/get-url";
@@ -56,10 +57,15 @@ export function translateResults(results, opts) {
 
   results.categories = results.categories
     .map(function (category) {
+      Site.current().updateCategory(category);
       return Category.list().findBy("id", category.id || category.model.id);
     })
     .compact();
 
+  results.grouped_search_result?.extra?.categories?.forEach((category) =>
+    Site.current().updateCategory(category)
+  );
+
   results.groups = results.groups
     .map((group) => {
       const name = escapeExpression(group.name);

app/serializers/grouped_search_result_serializer.rb

@@ -13,7 +13,8 @@ class GroupedSearchResultSerializer < ApplicationSerializer
              :search_log_id,
              :more_full_page_results,
              :can_create_topic,
-             :error
+             :error,
+             :extra
 
   def search_log_id
     object.search_log_id
@@ -30,4 +31,17 @@ def include_tags?
   def can_create_topic
     scope.can_create?(Topic)
   end
+
+  def extra
+    extra = {}
+
+    if object.can_lazy_load_categories
+      extra[:categories] = ActiveModel::ArraySerializer.new(
+        object.extra_categories,
+        each_serializer: BasicCategorySerializer,
+      )
+    end
+
+    extra
+  end
 end

lib/search.rb

@@ -266,6 +266,7 @@ def initialize(term, opts = nil)
         search_context: @search_context,
         blurb_length: @blurb_length,
         is_header_search: !use_full_page_limit,
+        can_lazy_load_categories: @guardian.can_lazy_load_categories?,
       )
   end
 
@@ -1447,7 +1448,7 @@ def topic_search
 
   def posts_eager_loads(query)
     query = query.includes(:user, :post_search_data)
-    topic_eager_loads = [:category]
+    topic_eager_loads = [{ category: :parent_category }]
 
     topic_eager_loads << :tags if SiteSetting.tagging_enabled
 

lib/search/grouped_search_results.rb

@@ -14,6 +14,7 @@ class TextHelper
       :type_filter,
       :posts,
       :categories,
+      :extra_categories,
       :users,
       :tags,
       :groups,
@@ -25,6 +26,7 @@ class TextHelper
       :more_full_page_results,
       :error,
       :use_pg_headlines_for_excerpt,
+      :can_lazy_load_categories,
     )
 
     attr_accessor :search_log_id
@@ -38,7 +40,8 @@ def initialize(
       blurb_length: nil,
       blurb_term: nil,
       is_header_search: false,
-      use_pg_headlines_for_excerpt: SiteSetting.use_pg_headlines_for_excerpt
+      use_pg_headlines_for_excerpt: SiteSetting.use_pg_headlines_for_excerpt,
+      can_lazy_load_categories: false
     )
       @type_filter = type_filter
       @term = term
@@ -47,12 +50,14 @@ def initialize(
       @blurb_length = blurb_length || BLURB_LENGTH
       @posts = []
       @categories = []
+      @extra_categories = Set.new
       @users = []
       @tags = []
       @groups = []
       @error = nil
       @is_header_search = is_header_search
       @use_pg_headlines_for_excerpt = use_pg_headlines_for_excerpt
+      @can_lazy_load_categories = can_lazy_load_categories
     end
 
     def error=(error)
@@ -101,6 +106,21 @@ def add(object)
       else
         (self.public_send(type)) << object
       end
+
+      if can_lazy_load_categories
+        category =
+          case type
+          when "posts"
+            object.topic.category
+          when "topics"
+            object.category
+          end
+
+        if category
+          extra_categories << category.parent_category if category.parent_category
+          extra_categories << category
+        end
+      end
     end
 
     def self.blurb_for(cooked: nil, term: nil, blurb_length: BLURB_LENGTH, scrub: true)

spec/requests/api/schemas/json/search_response.json

@@ -74,6 +74,17 @@
             "null"
           ]
         },
+        "extra": {
+          "type": "object",
+          "properties": {
+            "categories": {
+              "type": [
+                "array",
+                "null"
+              ]
+            }
+          }
+        },
         "post_ids": {
           "type": "array",
           "items": {

spec/requests/search_controller_spec.rb

@@ -495,6 +495,39 @@ def limited_request(ip_address = "1.2.3.4")
         end
       end
     end
+
+    context "with lazy loaded categories" do
+      fab!(:parent_category) { Fabricate(:category) }
+      fab!(:category) { Fabricate(:category, parent_category: parent_category) }
+      fab!(:other_category) { Fabricate(:category, parent_category: parent_category) }
+
+      fab!(:post) do
+        with_search_indexer_enabled do
+          topic = Fabricate(:topic, category: category)
+          Fabricate(:post, topic: topic, raw: "hello world. first topic")
+        end
+      end
+
+      fab!(:other_post) do
+        with_search_indexer_enabled do
+          topic = Fabricate(:topic, category: other_category)
+          Fabricate(:post, topic: topic, raw: "hello world. second topic")
+        end
+      end
+
+      before { SiteSetting.lazy_load_categories_groups = "#{Group::AUTO_GROUPS[:everyone]}" }
+
+      it "returns extra categories and parent categories" do
+        get "/search.json", params: { q: "hello" }
+
+        categories = response.parsed_body["grouped_search_result"]["extra"]["categories"]
+        expect(categories.map { |c| c["id"] }).to contain_exactly(
+          parent_category.id,
+          category.id,
+          other_category.id,
+        )
+      end
+    end
   end
 
   context "with search priority" do