Route accepts optional list of guard blocks

lib/webmachine/dispatcher/route.rb

@@ -14,24 +14,54 @@ class Route
       #   used to define this route (see #initialize).
       attr_reader :path_spec
 
+      # @return [Array<Proc>] the list of guard blocks used to define this
+      #   route (see #initialize).
+      attr_reader :guards
+
       # When used in a path specification, will match all remaining
       # segments
       MATCH_ALL = '*'.freeze
 
       # Creates a new Route that will associate a pattern to a
       # {Resource}.
-      # @param [Array<String|Symbol>] path_spec a list of path
-      #   segments (String) and identifiers (Symbol) to bind.
-      #   Strings will be simply matched for equality. Symbols in
-      #   the path spec will be extracted into {Request#path_info} for use
-      #   inside your {Resource}. The special segment {MATCH_ALL} will match
-      #   all remaining segments.
-      # @param [Class] resource the {Resource} to dispatch to
-      # @param [Hash] bindings additional information to add to
-      #   {Request#path_info} when this route matches
+      #
+      # @example Standard route
+      #   Route.new(["*"], MyResource)
+      #
+      # @example Guarded route
+      #   Route.new ["/notes"],
+      #     ->(request) { request.method == "POST" },
+      #     Resources::Note
+      #   Route.new ["/notes"], Resources::NoteList
+      #   Route.new ["/notes", :id], Resources::Note
+      #
+      # @overload initialize(path_spec, *guards, resource, bindings = {})
+      #   @param [Array<String|Symbol>] path_spec a list of path
+      #     segments (String) and identifiers (Symbol) to bind.
+      #     Strings will be simply matched for equality. Symbols in
+      #     the path spec will be extracted into {Request#path_info} for use
+      #     inside your {Resource}. The special segment {MATCH_ALL} will match
+      #     all remaining segments.
+      #   @param [Proc] guards optional guard blocks called with the request.
+      #   @param [Class] resource the {Resource} to dispatch to
+      #   @param [Hash] bindings additional information to add to
+      #     {Request#path_info} when this route matches
       # @see Dispatcher#add_route
-      def initialize(path_spec, resource, bindings={})
-        @path_spec, @resource, @bindings = path_spec, resource, bindings
+      def initialize(path_spec, *args)
+        if args.last.is_a? Hash
+          bindings = args.pop
+        else
+          bindings = {}
+        end
+
+        resource = args.pop
+        guards = args
+
+        @path_spec = path_spec
+        @guards    = guards
+        @resource  = resource
+        @bindings  =  bindings
+
         raise ArgumentError, t('not_resource_class', :class => resource.name) unless resource < Resource
       end
 
@@ -40,7 +70,7 @@ def initialize(path_spec, resource, bindings={})
       # @param [Reqeust] request the request object
       def match?(request)
         tokens = request.uri.path.match(/^\/(.*)/)[1].split('/')
-        bind(tokens, {})
+        guards.all? { |guard| guard[request] } && bind(tokens, {})
       end
 
       # Decorates the request with information about the dispatch

spec/webmachine/dispatcher/route_spec.rb

@@ -37,6 +37,50 @@
       it { should_not match_route [] }
       it { should_not match_route %w{bar *} }
     end
+
+    context "with a guard on the request method" do
+      let(:route) do
+        described_class.new(
+          ["notes"],
+          lambda { |request| request.method == "POST" },
+          resource
+        )
+      end
+
+      before do
+        request.uri.path = "/notes"
+      end
+
+      context "when guard returns true" do
+        before do
+          request.method.replace "POST"
+        end
+
+        it "returns true" do
+          route.match?(request).should be_true
+        end
+
+        context "but the path match fails" do
+          before do
+            request.uri.path = "/other"
+          end
+
+          it "returns false" do
+            route.match?(request).should be_false
+          end
+        end
+      end
+
+      context "when guard returns false" do
+        before do
+          request.method.replace "GET"
+        end
+
+        it "returns false" do
+          route.match?(request).should be_false
+        end
+      end
+    end
   end
 
   context "applying bindings" do