Merge in mongodb#1387, move functionality into document from timestamps.

CHANGELOG.md

@@ -26,6 +26,8 @@ For instructions on upgrading to newer versions, visit
 * \#1388 `model.add_to_set` now supports adding multiple values and performs an
   $addToSet with $each under the covers. (Christian Felder)
 
+* \#1387 Added `Model#cacheKey` for use in Rails caching. (Seivan Heidari)
+
 ### Resolved Issues
 
 * \#1449 New documents no longer get persisted when replaced on a has one as

lib/mongoid/document.rb

@@ -189,6 +189,27 @@ def becomes(klass)
       end
     end
 
+    # Print out the cache key. This will append different values on the
+    # plural model name.
+    #
+    # If new_record?     - will append /new
+    # If not             - will append /id-updated_at.to_s(:number)
+    # Without updated_at - will append /id
+    #
+    # This is usually called insode a cache() block
+    #
+    # @example Returns the cache key
+    #   document.cache_key
+    #
+    # @return [ String ] the string with or without updated_at
+    #
+    # @since 2.4.0
+    def cache_key
+      return "#{model_key}/new" if new_record?
+      return "#{model_key}/#{id}-#{updated_at.utc.to_s(:number)}" if updated_at
+      "#{model_key}/#{id}"
+    end
+
     private
 
     # Returns the logger
@@ -200,6 +221,18 @@ def logger
       Mongoid.logger
     end
 
+    # Get the name of the model used in caching.
+    #
+    # @example Get the model key.
+    #   model.model_key
+    #
+    # @return [ String ] The model key.
+    #
+    # @since 2.4.0
+    def model_key
+      @model_cache_key ||= "#{self.class.model_name.cache_key}"
+    end
+
     # Implement this for calls to flatten on array.
     #
     # @example Get the document as an array.

lib/mongoid/timestamps/updated.rb

@@ -21,29 +21,6 @@ module Updated
       def set_updated_at
         self.updated_at = Time.now.utc unless updated_at_changed?
       end
-
-      # Print out the cache key.
-      # Will append different values on the plural model name
-      # If new_record?     - will append /new
-      # If not             - will append /id-updated_at.to_s(:number)
-      # Without updated_at - will append /id
-
-      # This is usually called insode a cache() block
-      #
-      # @example Returns the cache key
-      # @return [String] the string with or without updated_at
-      def cache_key
-        case
-        when new_record?
-          "#{self.class.model_name.cache_key}/new"
-        when timestamp = self[:updated_at]
-          timestamp = timestamp.utc.to_s(:number)
-          "#{self.class.model_name.cache_key}/#{id}-#{timestamp}"
-        else
-          "#{self.class.model_name.cache_key}/#{id}"
-        end
-      end
-
     end
   end
 end

spec/unit/mongoid/document_spec.rb

@@ -239,6 +239,49 @@
     end
   end
 
+  describe "#cache_key" do
+
+    let(:person) do
+      Person.new
+    end
+
+    context "when the document is new" do
+
+      it "should have a new key name" do
+        person.cache_key.should eq("people/new")
+      end
+    end
+
+    context "when persisted" do
+
+      before do
+        person.save
+      end
+
+      context "with updated_at" do
+
+        let!(:updated_at) do
+          person.updated_at.utc.to_s(:number)
+        end
+
+        it "should have the id and updated_at key name" do
+          person.cache_key.should eq("people/#{person.id}-#{updated_at}")
+        end
+      end
+
+      context "without updated_at" do
+
+        before do
+          person.updated_at = nil
+        end
+
+        it "should have the id key name" do
+          person.cache_key.should eq("people/#{person.id}")
+        end
+      end
+    end
+  end
+
   describe "#hash" do
 
     let(:person) do

spec/unit/mongoid/timestamps_spec.rb

@@ -82,46 +82,4 @@
       person.updated_at.should be_within(10).of(Time.now.utc)
     end
   end
-
-  describe "#cache_key" do
-    let(:person) do
-      Person.new
-    end
-
-    let(:fields) do
-      Person.fields
-    end
-
-    context "when the document is new" do
-      it "should have a new key name" do
-        person.cache_key.should eq "people/new"
-      end
-    end
-
-    context "when persisted" do
-
-      before do
-        person.save
-      end
-
-      context "with updated_at" do
-        it "should have the id and updated_at key name" do
-          updated_at = person.updated_at.utc.to_s(:number)
-          person.cache_key.should eq "people/#{person.id}-#{updated_at}"
-        end
-      end
-
-      context "without updated_at" do
-        it "should have the id key name" do        
-          person.updated_at = nil
-          person.cache_key.should eq "people/#{person.id}"
-        end
-      end
-
-
-    end
-
-
-  end
-
 end