From 5fb655b6bf8deccfb4b8e7f60dfae8fc3b5aef9c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9rgio=20Saquetim?= <saquetim@discourse.org>
Date: Fri, 21 Oct 2022 02:01:37 -0300
Subject: [PATCH] WIP: Some hooks for perfomance optimizations in
 `discourse-circles`

---
 app/controllers/groups_controller.rb |  5 ++++
 app/models/category_list.rb          |  5 ++++
 app/models/site.rb                   | 36 ++++++++++++++++++----------
 3 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/app/controllers/groups_controller.rb b/app/controllers/groups_controller.rb
index 4a772039f6..26233eb33a 100644
--- a/app/controllers/groups_controller.rb
+++ b/app/controllers/groups_controller.rb
@@ -80,6 +80,11 @@ class GroupsController < ApplicationController
       type_filters = type_filters - %i[my owner]
     end
 
+    modifiers = []
+    # some plugins may need to change the query
+    DiscourseEvent.trigger(:query_groups_list, modifiers, groups, @guardian, params)
+    modifiers.each { |mod| groups = mod.call(groups) }
+
     type_filters.delete(:non_automatic)
 
     # count the total before doing pagination
diff --git a/app/models/category_list.rb b/app/models/category_list.rb
index 38a55042a7..62d5f8829b 100644
--- a/app/models/category_list.rb
+++ b/app/models/category_list.rb
@@ -121,6 +121,11 @@ class CategoryList
 
     @categories = self.class.order_categories(@categories)
 
+    modifiers = []
+    # some plugins may need to change the categories cached on site load
+    DiscourseEvent.trigger(:query_categories_list, modifiers, @categories, @guardian, @options)
+    modifiers.each { |mod| @categories = mod.call(@categories) }
+
     @categories = @categories.to_a
 
     include_subcategories = @options[:include_subcategories] == true
diff --git a/app/models/site.rb b/app/models/site.rb
index 5d3b4565bc..b8d60fbda3 100644
--- a/app/models/site.rb
+++ b/app/models/site.rb
@@ -71,19 +71,29 @@ class Site
       .cache
       .fetch(categories_cache_key, expires_in: 30.minutes) do
         categories =
-          Category
-            .includes(
-              :uploaded_logo,
-              :uploaded_logo_dark,
-              :uploaded_background,
-              :tags,
-              :tag_groups,
-              category_required_tag_groups: :tag_group,
-            )
-            .joins("LEFT JOIN topics t on t.id = categories.topic_id")
-            .select("categories.*, t.slug topic_slug")
-            .order(:position)
-            .to_a
+          begin
+            query =
+              Category
+                .includes(
+                  :uploaded_logo,
+                  :uploaded_logo_dark,
+                  :uploaded_background,
+                  :tags,
+                  :tag_groups,
+                  category_required_tag_groups: :tag_group,
+                )
+                .joins("LEFT JOIN topics t on t.id = categories.topic_id")
+                .select("categories.*, t.slug topic_slug")
+                .order(:position)
+                .to_a
+
+            modifiers = []
+            # some plugins may need to change the categories cached on site load
+            DiscourseEvent.trigger(:site_query_categories, modifiers, query, @guardian)
+            modifiers.each { |mod| query = mod.call(query) }
+
+            query.to_a
+          end
 
         if preloaded_category_custom_fields.present?
           Category.preload_custom_fields(categories, preloaded_category_custom_fields)