Abstract: Jini has served Orbitz well, but at the cost of tight coupling due in part to shared code and Java™ platform serialization rules. To improve agility, Orbitz is migrating to a RESTful Web services architecture using protocol buffers to define message formats. The result is loosely coupled services with autonomous lifecycles supporting evolvability and innovative mashup-style development. This session is intended for experienced architects and tech leads who are familiar with distributed systems and data encoding methods. It covers • Using document schemas to constitute language-neutral contracts • Using standard HTTP plumbing and intermediaries • Implementing a reverse proxy for request routing based on RESTful URLs • Applying OLAs for governance and service isolation • Writing automated service layer tests to ensure backward compatibility

1. RESTful Protocol Buffers Matt O’Keefe/Alex Antonov Sears Holdings/Orbitz Worldwide

7. Why REST? Uniform Interface http://rest.blueoxen.net/cgi-bin/wiki.pl?HttpMethods http://rest.blueoxen.net/cgi-bin/wiki.pl?HttpMethods Method Safe Idempotent Visible Semantics Identifiable Resource Cacheable GET X X X X X HEAD X X X X X PUT X X X POST DELETE X X X OPTIONS X X X Method Safe Idempotent Visible Semantics Identifiable Resource Cacheable GET X X X X X HEAD X X X X X PUT X X X POST DELETE X X X OPTIONS X X X

8. Why REST? Simplicity of HTTP

9. Why REST? HTTP Intermediaries

13. Why Protocol Buffers? Evolvability for Agile Oriented Architecture

20. Building a Client // EmployeeServiceClient .java public interface EmployeeServiceClient { @ServiceName( value = ”getEmployeeById" ) public Employee getEmployeeById(@ParamName( "id" ) int employeeId ); } // employee.proto package employee; message Employee { required int32 id = 1; optional string name = 2; repeated Role role = 3; enum Role { DEVELOPER = 1; MANAGER = 2; } } // EmployeeServiceClient .java public interface EmployeeServiceClient { @ServiceName( value = ”getEmployeeById" ) public Employee getEmployeeById(@ParamName( "id" ) int employeeId ); } // employee.proto package employee; message Employee { required int32 id = 1; optional string name = 2; repeated Role role = 3; enum Role { DEVELOPER = 1; MANAGER = 2; } }

33. Matt O’Keefe/Alex Antonov [email_address] [email_address] Matt O’Keefe/Alex Antonov [email_address] [email_address]