Extract Notification::Groups concern (#32968)

app/models/concerns/notification/groups.rb

@@ -0,0 +1,123 @@
+# frozen_string_literal: true
+
+module Notification::Groups
+  extend ActiveSupport::Concern
+
+  # `set_group_key!` needs to be updated if this list changes
+  GROUPABLE_NOTIFICATION_TYPES = %i(favourite reblog follow).freeze
+  MAXIMUM_GROUP_SPAN_HOURS = 12
+
+  def set_group_key!
+    return if filtered? || GROUPABLE_NOTIFICATION_TYPES.exclude?(type)
+
+    type_prefix = case type
+                  when :favourite, :reblog
+                    [type, target_status&.id].join('-')
+                  when :follow
+                    type
+                  else
+                    raise NotImplementedError
+                  end
+    redis_key   = "notif-group/#{account.id}/#{type_prefix}"
+    hour_bucket = activity.created_at.utc.to_i / 1.hour.to_i
+
+    # Reuse previous group if it does not span too large an amount of time
+    previous_bucket = redis.get(redis_key).to_i
+    hour_bucket = previous_bucket if hour_bucket < previous_bucket + MAXIMUM_GROUP_SPAN_HOURS
+
+    # We do not concern ourselves with race conditions since we use hour buckets
+    redis.set(redis_key, hour_bucket, ex: MAXIMUM_GROUP_SPAN_HOURS.hours.to_i)
+
+    self.group_key = "#{type_prefix}-#{hour_bucket}"
+  end
+
+  class_methods do
+    def paginate_groups(limit, pagination_order, grouped_types: nil)
+      raise ArgumentError unless %i(asc desc).include?(pagination_order)
+
+      query = reorder(id: pagination_order)
+
+      # Ideally `:types` would be a bind rather than part of the SQL itself, but that does not
+      # seem to be possible to do with Rails, considering that the expression would occur in
+      # multiple places, including in a `select`
+      group_key_sql = begin
+        if grouped_types.present?
+          # Normalize `grouped_types` so the number of different SQL query shapes remains small, and
+          # the queries can be analyzed in monitoring/telemetry tools
+          grouped_types = (grouped_types.map(&:to_sym) & GROUPABLE_NOTIFICATION_TYPES).sort
+
+          sanitize_sql_array([<<~SQL.squish, { types: grouped_types }])
+            COALESCE(
+              CASE
+                WHEN notifications.type IN (:types) THEN notifications.group_key
+                ELSE NULL
+              END,
+              'ungrouped-' || notifications.id
+            )
+          SQL
+        else
+          "COALESCE(notifications.group_key, 'ungrouped-' || notifications.id)"
+        end
+      end
+
+      unscoped
+        .with_recursive(
+          grouped_notifications: [
+            # Base case: fetching one notification and annotating it with visited groups
+            query
+              .select('notifications.*', "ARRAY[#{group_key_sql}] AS groups")
+              .limit(1),
+            # Recursive case, always yielding at most one annotated notification
+            unscoped
+              .from(
+                [
+                  # Expose the working table as `wt`, but quit early if we've reached the limit
+                  unscoped
+                    .select('id', 'groups')
+                    .from('grouped_notifications')
+                    .where('array_length(grouped_notifications.groups, 1) < :limit', limit: limit)
+                    .arel.as('wt'),
+                  # Recursive query, using `LATERAL` so we can refer to `wt`
+                  query
+                    .where(pagination_order == :desc ? 'notifications.id < wt.id' : 'notifications.id > wt.id')
+                    .where.not("#{group_key_sql} = ANY(wt.groups)")
+                    .limit(1)
+                    .arel.lateral('notifications'),
+                ]
+              )
+              .select('notifications.*', "array_append(wt.groups, #{group_key_sql}) AS groups"),
+          ]
+        )
+        .from('grouped_notifications AS notifications')
+        .order(id: pagination_order)
+        .limit(limit)
+    end
+
+    # This returns notifications from the request page, but with at most one notification per group.
+    # Notifications that have no `group_key` each count as a separate group.
+    def paginate_groups_by_max_id(limit, max_id: nil, since_id: nil, grouped_types: nil)
+      query = reorder(id: :desc)
+      query = query.where(id: ...(max_id.to_i)) if max_id.present?
+      query = query.where(id: (since_id.to_i + 1)...) if since_id.present?
+      query.paginate_groups(limit, :desc, grouped_types: grouped_types)
+    end
+
+    # Differs from :paginate_groups_by_max_id in that it gives the results immediately following min_id,
+    # whereas since_id gives the items with largest id, but with since_id as a cutoff.
+    # Results will be in ascending order by id.
+    def paginate_groups_by_min_id(limit, max_id: nil, min_id: nil, grouped_types: nil)
+      query = reorder(id: :asc)
+      query = query.where(id: (min_id.to_i + 1)...) if min_id.present?
+      query = query.where(id: ...(max_id.to_i)) if max_id.present?
+      query.paginate_groups(limit, :asc, grouped_types: grouped_types)
+    end
+
+    def to_a_grouped_paginated_by_id(limit, options = {})
+      if options[:min_id].present?
+        paginate_groups_by_min_id(limit, min_id: options[:min_id], max_id: options[:max_id], grouped_types: options[:grouped_types]).reverse
+      else
+        paginate_groups_by_max_id(limit, max_id: options[:max_id], since_id: options[:since_id], grouped_types: options[:grouped_types]).to_a
+      end
+    end
+  end
+end

app/models/notification.rb

@@ -19,6 +19,7 @@
 class Notification < ApplicationRecord
   self.inheritance_column = nil
 
+  include Notification::Groups
   include Paginable
   include Redisable
 
@@ -31,10 +32,6 @@ class Notification < ApplicationRecord
     'Poll' => :poll,
   }.freeze
 
-  # `set_group_key!` needs to be updated if this list changes
-  GROUPABLE_NOTIFICATION_TYPES = %i(favourite reblog follow).freeze
-  MAXIMUM_GROUP_SPAN_HOURS = 12
-
   # Please update app/javascript/api_types/notification.ts if you change this
   PROPERTIES = {
     mention: {
@@ -130,30 +127,6 @@ class Notification < ApplicationRecord
     end
   end
 
-  def set_group_key!
-    return if filtered? || Notification::GROUPABLE_NOTIFICATION_TYPES.exclude?(type)
-
-    type_prefix = case type
-                  when :favourite, :reblog
-                    [type, target_status&.id].join('-')
-                  when :follow
-                    type
-                  else
-                    raise NotImplementedError
-                  end
-    redis_key   = "notif-group/#{account.id}/#{type_prefix}"
-    hour_bucket = activity.created_at.utc.to_i / 1.hour.to_i
-
-    # Reuse previous group if it does not span too large an amount of time
-    previous_bucket = redis.get(redis_key).to_i
-    hour_bucket = previous_bucket if hour_bucket < previous_bucket + MAXIMUM_GROUP_SPAN_HOURS
-
-    # We do not concern ourselves with race conditions since we use hour buckets
-    redis.set(redis_key, hour_bucket, ex: MAXIMUM_GROUP_SPAN_HOURS.hours.to_i)
-
-    self.group_key = "#{type_prefix}-#{hour_bucket}"
-  end
-
   class << self
     def browserable(types: [], exclude_types: [], from_account_id: nil, include_filtered: false)
       requested_types = if types.empty?
@@ -171,94 +144,6 @@ class Notification < ApplicationRecord
       end
     end
 
-    def paginate_groups(limit, pagination_order, grouped_types: nil)
-      raise ArgumentError unless %i(asc desc).include?(pagination_order)
-
-      query = reorder(id: pagination_order)
-
-      # Ideally `:types` would be a bind rather than part of the SQL itself, but that does not
-      # seem to be possible to do with Rails, considering that the expression would occur in
-      # multiple places, including in a `select`
-      group_key_sql = begin
-        if grouped_types.present?
-          # Normalize `grouped_types` so the number of different SQL query shapes remains small, and
-          # the queries can be analyzed in monitoring/telemetry tools
-          grouped_types = (grouped_types.map(&:to_sym) & GROUPABLE_NOTIFICATION_TYPES).sort
-
-          sanitize_sql_array([<<~SQL.squish, { types: grouped_types }])
-            COALESCE(
-              CASE
-                WHEN notifications.type IN (:types) THEN notifications.group_key
-                ELSE NULL
-              END,
-              'ungrouped-' || notifications.id
-            )
-          SQL
-        else
-          "COALESCE(notifications.group_key, 'ungrouped-' || notifications.id)"
-        end
-      end
-
-      unscoped
-        .with_recursive(
-          grouped_notifications: [
-            # Base case: fetching one notification and annotating it with visited groups
-            query
-              .select('notifications.*', "ARRAY[#{group_key_sql}] AS groups")
-              .limit(1),
-            # Recursive case, always yielding at most one annotated notification
-            unscoped
-              .from(
-                [
-                  # Expose the working table as `wt`, but quit early if we've reached the limit
-                  unscoped
-                    .select('id', 'groups')
-                    .from('grouped_notifications')
-                    .where('array_length(grouped_notifications.groups, 1) < :limit', limit: limit)
-                    .arel.as('wt'),
-                  # Recursive query, using `LATERAL` so we can refer to `wt`
-                  query
-                    .where(pagination_order == :desc ? 'notifications.id < wt.id' : 'notifications.id > wt.id')
-                    .where.not("#{group_key_sql} = ANY(wt.groups)")
-                    .limit(1)
-                    .arel.lateral('notifications'),
-                ]
-              )
-              .select('notifications.*', "array_append(wt.groups, #{group_key_sql}) AS groups"),
-          ]
-        )
-        .from('grouped_notifications AS notifications')
-        .order(id: pagination_order)
-        .limit(limit)
-    end
-
-    # This returns notifications from the request page, but with at most one notification per group.
-    # Notifications that have no `group_key` each count as a separate group.
-    def paginate_groups_by_max_id(limit, max_id: nil, since_id: nil, grouped_types: nil)
-      query = reorder(id: :desc)
-      query = query.where(id: ...(max_id.to_i)) if max_id.present?
-      query = query.where(id: (since_id.to_i + 1)...) if since_id.present?
-      query.paginate_groups(limit, :desc, grouped_types: grouped_types)
-    end
-
-    # Differs from :paginate_groups_by_max_id in that it gives the results immediately following min_id,
-    # whereas since_id gives the items with largest id, but with since_id as a cutoff.
-    # Results will be in ascending order by id.
-    def paginate_groups_by_min_id(limit, max_id: nil, min_id: nil, grouped_types: nil)
-      query = reorder(id: :asc)
-      query = query.where(id: (min_id.to_i + 1)...) if min_id.present?
-      query = query.where(id: ...(max_id.to_i)) if max_id.present?
-      query.paginate_groups(limit, :asc, grouped_types: grouped_types)
-    end
-
-    def to_a_grouped_paginated_by_id(limit, options = {})
-      if options[:min_id].present?
-        paginate_groups_by_min_id(limit, min_id: options[:min_id], max_id: options[:max_id], grouped_types: options[:grouped_types]).reverse
-      else
-        paginate_groups_by_max_id(limit, max_id: options[:max_id], since_id: options[:since_id], grouped_types: options[:grouped_types]).to_a
-      end
-    end
-
     def preload_cache_collection_target_statuses(notifications, &_block)
       notifications.group_by(&:type).each do |type, grouped_notifications|
         associations = TARGET_STATUS_INCLUDES_BY_TYPE[type]