init project

app/services/reward_grade_service.rb

@@ -0,0 +1,19 @@
+class RewardGradeService < ApplicationService
+  attr_reader :user, :attrs, :not_unique
+
+  def initialize(user, **attrs)
+    @user  = user
+    @not_unique = attrs.delete(:not_unique) || false
+    @attrs = attrs.slice(*%i[container_id container_type score])
+  end
+
+  def call
+    return if user.grades.exists?(attrs) && !not_unique
+
+    ActiveRecord::Base.transaction do
+      grade = user.grades.create!(attrs)
+
+      user.increment!(:grade, grade.score)
+    end
+  end
+end