lib/flipper/adapter.rb in flipper-0.2.1 vs lib/flipper/adapter.rb in flipper-0.3.0

@@ -1,7 +1,9 @@
 module Flipper
-  # Internal: Adapter wrapper that wraps vanilla adapter instances with local caching.
+  # Internal: Adapter wrapper that wraps vanilla adapter instances. Adds things
+  # like local caching and convenience methods for adding/reading features from
+  # the adapter.
   #
   # So what is this local cache crap?
   #
   # The main goal of the local cache is to prevent multiple queries to an
   # adapter for the same key for a given amount of time (per request, per
@@ -15,10 +17,12 @@
   # Examples
   #
   # To see an example adapter that this would wrap, checkout the [memory
   # adapter included with flipper](https://github.com/jnunemaker/flipper/blob/master/lib/flipper/adapters/memory.rb).
   class Adapter
+    FeaturesKey = 'features'
+
     # Internal: Wraps vanilla adapter instance for use internally in flipper.
     #
     # object - Either an instance of Flipper::Adapter or a vanilla adapter instance
     #
     # Examples
@@ -63,52 +67,60 @@
     def using_local_cache?
       @use_local_cache == true
     end
 
     def read(key)
-      if using_local_cache?
-        cache(key) { @adapter.read(key) }
-      else
-        @adapter.read(key)
-      end
+      perform_read(key) { @adapter.read(key) }
     end
 
     def write(key, value)
-      @adapter.write(key, value).tap { expire_local_cache(key) }
+      perform_update(key) { @adapter.write(key, value) }
     end
 
     def delete(key)
-      @adapter.delete(key).tap { expire_local_cache(key) }
+      perform_update(key) { @adapter.delete(key) }
     end
 
     def set_members(key)
-      if using_local_cache?
-        cache(key) { @adapter.set_members(key) }
-      else
-        @adapter.set_members(key)
-      end
+      perform_read(key) { @adapter.set_members(key) }
     end
 
     def set_add(key, value)
-      @adapter.set_add(key, value).tap { expire_local_cache(key) }
+      perform_update(key) { @adapter.set_add(key, value) }
     end
 
     def set_delete(key, value)
-      @adapter.set_delete(key, value).tap { expire_local_cache(key) }
+      perform_update(key) { @adapter.set_delete(key, value) }
     end
 
     def eql?(other)
       self.class.eql?(other.class) && adapter == other.adapter
     end
     alias :== :eql?
 
+    def features
+      set_members(FeaturesKey)
+    end
+
+    def feature_add(name)
+      set_add(FeaturesKey, name.to_s)
+    end
+
     private
 
-    def cache(key)
-      local_cache.fetch(key) { local_cache[key] = yield }
+    def perform_read(key)
+      if using_local_cache?
+        local_cache.fetch(key.to_s) { local_cache[key.to_s] = yield }
+      else
+        yield
+      end
     end
 
-    def expire_local_cache(key)
-      local_cache.delete(key) if using_local_cache?
+    def perform_update(key)
+      result = yield
+      if using_local_cache?
+        local_cache.delete(key.to_s)
+      end
+      result
     end
   end
 end