transferred Code Ocean from original repository to GitHub

app/policies/exercise_policy.rb

@@ -0,0 +1,24 @@
+class ExercisePolicy < AdminOrAuthorPolicy
+  def author?
+    @user == @record.author
+  end
+  private :author?
+
+  [:clone?, :statistics?].each do |action|
+    define_method(action) { admin? || author? }
+  end
+
+  [:implement?, :submit?].each do |action|
+    define_method(action) { everyone }
+  end
+
+  class Scope < Scope
+    def resolve
+      if @user.admin?
+        @scope.all
+      else
+        @scope.where("user_id = #{@user.id} OR public = TRUE")
+      end
+    end
+  end
+end