Add in-app notifications for moderation actions/warnings (#30065)

app/serializers/rest/account_warning_serializer.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+class REST::AccountWarningSerializer < ActiveModel::Serializer
+  attributes :id, :action, :text, :status_ids, :created_at
+
+  has_one :target_account, serializer: REST::AccountSerializer
+  has_one :appeal, serializer: REST::AppealSerializer
+
+  def id
+    object.id.to_s
+  end
+
+  def status_ids
+    object&.status_ids&.map(&:to_s)
+  end
+end

app/serializers/rest/appeal_serializer.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class REST::AppealSerializer < ActiveModel::Serializer
+  attributes :text, :state
+
+  def state
+    if object.approved?
+      'approved'
+    elsif object.rejected?
+      'rejected'
+    else
+      'pending'
+    end
+  end
+end

app/serializers/rest/notification_serializer.rb

@@ -7,6 +7,7 @@ class REST::NotificationSerializer < ActiveModel::Serializer
   belongs_to :target_status, key: :status, if: :status_type?, serializer: REST::StatusSerializer
   belongs_to :report, if: :report_type?, serializer: REST::ReportSerializer
   belongs_to :account_relationship_severance_event, key: :event, if: :relationship_severance_event?, serializer: REST::AccountRelationshipSeveranceEventSerializer
+  belongs_to :account_warning, key: :moderation_warning, if: :moderation_warning_event?, serializer: REST::AccountWarningSerializer
 
   def id
     object.id.to_s
@@ -23,4 +24,8 @@ class REST::NotificationSerializer < ActiveModel::Serializer
   def relationship_severance_event?
     object.type == :severed_relationships
   end
+
+  def moderation_warning_event?
+    object.type == :moderation_warning
+  end
 end