Add middleware & railtie

lib/robinet.rb

@@ -10,5 +10,8 @@ def require_libs(*libs)
   end
   self.root_path = File.expand_path '..', __FILE__
   self.lib_path = File.expand_path '../robinet', __FILE__
-  require_libs 'storage', 'strategy', 'parser', 'limit'
+  require_libs(
+      'config', 'errors', 'storage', 'strategy',
+      'parser', 'limit', 'limiter', 'railtie', 'middleware'
+  )
 end

lib/robinet/limiter.rb

@@ -0,0 +1,12 @@
+module Robinet
+  class Limiter
+
+    def initialize(app)
+      @app = app
+    end
+
+    def execute(request)
+      raise Errors::RateLimitExceeded
+    end
+  end
+end

lib/robinet/middleware.rb

@@ -0,0 +1,24 @@
+module Robinet
+  class Middleware
+    def initialize(app)
+      @app = app
+      @limiter = Robinet::Limiter.new(@app)
+    end
+
+    def call(env)
+      request = Rack::Request.new(env)
+      begin
+        check_limits(request)
+        @app.call(env)
+      rescue Errors::RateLimitExceeded => e
+        e.http_response
+      end
+    end
+
+    private
+
+    def check_limits(request)
+      @limiter.execute(request)
+    end
+  end
+end

lib/robinet/railtie.rb

@@ -0,0 +1,10 @@
+module Robinet
+  class Railtie < Rails::Railtie
+    initializer 'robinet.add_middleware' do |application|
+      if Robinet.config.enabled
+        Robinet.logger.info('Enabling Robinet Rate Limiter')
+        application.middleware.use Robinet::Middleware
+      end
+    end
+  end if defined?(Rails)
+end