Adds a after filter

README.rdoc

@@ -211,6 +211,12 @@ These are run in Sinatra::EventContext before every event.
     .. this code will run before each event ..
   end
 
+These are run in Sinatra::EventContext after every event.
+
+  after do
+    .. this code will run after each event ..
+  end
+
 == Halt!
 
 To immediately stop a request during a before filter or event use:

lib/sinatra.rb

@@ -872,7 +872,7 @@ class Application
     # Hash of template name mappings.
     attr_reader :templates
 
-    # Hash of filters with event name keys (:before) and arrays of
+    # Hash of filters with event name keys (:before, :after) and arrays of
     # handlers as values.
     attr_reader :filters
 
@@ -888,7 +888,7 @@ class Application
     # top-level the method is forwarded to the default application
     # (Sinatra::application).
     FORWARD_METHODS = %w[
-      get put post delete head template layout before error not_found
+      get put post delete head template layout before after error not_found
       configures configure set set_options set_option enable disable use
       development? test? production?
     ]
@@ -1123,6 +1123,7 @@ def not_found(options={}, &b)
 
     # Define a request filter. When <tt>type</tt> is <tt>:before</tt>, execute the
     # block in the context of each request before matching event handlers.
+    # <tt>:after</tt> executes after each request handler executes.
     def filter(type, &b)
       filters[type] << b
     end
@@ -1133,6 +1134,12 @@ def before(&b)
       filter :before, &b
     end
 
+    # Invoke the block in the context of each request after invoking
+    # matching event handler.
+    def after(&b)
+      filter :after, &b
+    end
+
     # True when environment is :development.
     def development? ; options.env == :development ; end
 
@@ -1236,7 +1243,8 @@ def call(env)
     # 3. Create new EventContext to house event handler evaluation.
     # 4. Invoke each #before filter in context of EventContext object.
     # 5. Invoke event handler in context of EventContext object.
-    # 6. Return response to Rack.
+    # 6. Invoke each #after filter in the context of EventContext object.
+    # 7. Return response to Rack.
     #
     # See the Rack specification for detailed information on the
     # +env+ argument and return value.
@@ -1251,7 +1259,9 @@ def dispatch(env)
             context.route_params = result.params
             context.response.status = result.status
             context.reset!
-            [:complete, context.instance_eval(&result.block)]
+            r = context.instance_eval(&result.block)
+            filters[:after].each { |f| context.instance_eval(&f) }
+            [:complete, r]
           end
         body = returned.to_result(context)
       rescue => e

test/filter_test.rb

@@ -28,3 +28,22 @@
   end
 
 end
+
+context "after filters" do
+
+  setup do
+    Sinatra.application = nil
+    @app = Sinatra.application
+  end
+
+  specify "should be executed after the request" do
+    invoked = 0
+    @app.before { invoked = 2 }
+    @app.get('/') { invoked += 2 }
+    @app.after { invoked *= 2 }
+    get_it '/'
+    should.be.ok
+    invoked.should.be == 8
+  end
+
+end