Add trending statuses (#17431)

* Add trending statuses

* Fix dangling items with stale scores in localized sets

* Various fixes and improvements

- Change approve_all/reject_all to approve_accounts/reject_accounts
- Change Trends::Query methods to not mutate the original query
- Change Trends::Query#skip to offset
- Change follow recommendations to be refreshed in a transaction

* Add tests for trending statuses filtering behaviour

* Fix not applying filtering scope in controller

1 files changed, 10 insertions, 26 deletions

diff --git a/app/models/trends/tags.rb b/app/models/trends/tags.rb
index 2ea4550df..3caa58815 100644
--- a/app/models/trends/tags.rb
+++ b/app/models/trends/tags.rb
@@ -5,7 +5,7 @@ class Trends::Tags < Trends::Base
 
   self.default_options = {
     threshold: 5,
-    review_threshold: 10,
+    review_threshold: 3,
     max_score_cooldown: 2.days.freeze,
     max_score_halflife: 4.hours.freeze,
   }
@@ -29,27 +29,15 @@ class Trends::Tags < Trends::Base
     trim_older_items
   end
 
-  def get(allowed, limit)
-    tag_ids = currently_trending_ids(allowed, limit)
-    tags = Tag.where(id: tag_ids).index_by(&:id)
-    tag_ids.map { |id| tags[id] }.compact
-  end
-
   def request_review
     tags = Tag.where(id: currently_trending_ids(false, -1))
 
-    tags_requiring_review = tags.filter_map do |tag|
+    tags.filter_map do |tag|
       next unless would_be_trending?(tag.id) && !tag.trendable? && tag.requires_review_notification?
 
       tag.touch(:requested_review_at)
       tag
     end
-
-    return if tags_requiring_review.empty?
-
-    User.staff.includes(:account).find_each do |user|
-      AdminMailer.new_trending_tags(user.account, tags_requiring_review).deliver_later! if user.allows_trending_tag_emails?
-    end
   end
 
   protected
@@ -58,6 +46,10 @@ class Trends::Tags < Trends::Base
     PREFIX
   end
 
+  def klass
+    Tag
+  end
+
   private
 
   def calculate_scores(tags, at_time)
@@ -87,18 +79,10 @@ class Trends::Tags < Trends::Base
 
       decaying_score = max_score * (0.5**((at_time.to_f - max_time.to_f) / options[:max_score_halflife].to_f))
 
-      if decaying_score.zero?
-        redis.zrem("#{PREFIX}:all", tag.id)
-        redis.zrem("#{PREFIX}:allowed", tag.id)
-      else
-        redis.zadd("#{PREFIX}:all", decaying_score, tag.id)
-
-        if tag.trendable?
-          redis.zadd("#{PREFIX}:allowed", decaying_score, tag.id)
-        else
-          redis.zrem("#{PREFIX}:allowed", tag.id)
-        end
-      end
+      add_to_and_remove_from_subsets(tag.id, decaying_score, {
+        all: true,
+        allowed: tag.trendable?,
+      })
     end
   end