1 files changed, 32 insertions, 0 deletions
diff --git a/lib/declarative_policy/cache.rb b/lib/declarative_policy/cache.rb
new file mode 100644
index 00000000000..b8cc60074c7
--- /dev/null
+++ b/lib/declarative_policy/cache.rb
@@ -0,0 +1,32 @@
+module DeclarativePolicy
+  module Cache
+    class << self
+      def user_key(user)
+        return '<anonymous>' if user.nil?
+        id_for(user)
+      end
+
+      def policy_key(user, subject)
+        u = user_key(user)
+        s = subject_key(subject)
+        "/dp/policy/#{u}/#{s}"
+      end
+
+      def subject_key(subject)
+        return '<nil>' if subject.nil?
+        return subject.inspect if subject.is_a?(Symbol)
+        "#{subject.class.name}:#{id_for(subject)}"
+      end
+
+      private
+
+      def id_for(obj)
+        if obj.respond_to?(:id) && obj.id
+          obj.id.to_s
+        else
+          "##{obj.object_id}"
+        end
+      end
+    end
+  end
+end