Imported a simple calc-server.ru example RPC service.

doc/examples/calc-server.ru

@@ -0,0 +1,31 @@
+#!/usr/bin/env rackup
+$:.unshift(File.expand_path(File.join(File.dirname(__FILE__), '..', '..', 'lib')))
+require 'rack/rpc'
+
+module Calc
+  class Add < Rack::RPC::Operation
+    operand :a, Numeric
+    operand :b, Numeric
+
+    def execute
+      @a + @b
+    end
+  end
+
+  class Multiply < Rack::RPC::Operation
+    operand :a, Numeric
+    operand :b, Numeric
+
+    def execute
+      @a * @b
+    end
+  end
+
+  class Service < Rack::RPC::Service
+    operator Add
+    operator Multiply
+  end
+end # Calc
+
+use Rack::RPC::Endpoint, Calc::Service.new, :path => '/rpc'
+run lambda { |env| [200, {'Content-Type' => 'text/plain', 'Location' => '/rpc'}, []] }