Web Services: Life Cycle Intelligence

Transcription

1 Web Services: Life Cycle Intelligence A/Prof. Boualem Benatallah School of Computer Science and Engineering The University of New South Wales (UNSW) Boualem Benatallah,

2 Agenda Service Oriented Computing: principles and issues ServiceMosaic Project: Service Lifecycle Intelligence Boualem Benatallah,

3 Material based on work in ServiceMosaic project, collaboration with: Dr. Fabio Casati (HP Labs, USA) Dr. Regis Saint-Paul (UNSW, Australia) Mr. Hamid Motahari (UNSW, Australia) Ms. Woralak Kongdenfha (UNSW, Australia) Mr. Julien Ponge (LIMOS, France) Dr. Farouk Toumani (LIMOS, France) Prof. Mohand-said Hacid (LIRIS, France) Web sites servicemosaic.isima.fr Boualem Benatallah,

4 Development of Integrated Applications Applications and data sources are autonomously developed and deployed Proprietary technologies (communication protocols, data formats) Rigid infrastructures, costly development and maintenance of integrated systems 4

5 Service Oriented Architectures (SOA) J2EE APPLICATION LEGACY SYSTEMS.NET APPLICATION Standard protocols and languages Agile infrastructures XML WEB SERVICES SOAP PARTNER SYSTEM PARTNER SYSTEM 5

6 Principles Facilitate programmatic interactions of autonomous systems (e.g., data-intensive, computational resources) via resource virtualization, infrastructure simplification and consolidation Web services: self-described software entities (at least best possible description), that can be published, discovered, and invoked over the network (using XML-based standard languages and protocols) On demand computing through composition Services are poised to be as ubiquitous as the Internet (e.g., payroll, on-board systems, e- government, services at your computer) Boualem Benatallah,

7 Issues Relevant to Various Service Life Cycle Activities Semantic Interoperability SOA solved low level interoperability but for programming by composition to scale, services should be used with assistance from providers Richer component model (possible interactions, OoS, data types) Various integration layers (e.g., data, process) Aligning IT services with business services Correlation of higher level abstractions to lower-level system observable events Continuous monitoring of resources and processes Evolution and change management Contract violation, impact analysis and process migration 7

8 Current Standards Maze BPML ebxml WS-Attachments XrML WSDL WS-Reliability WS-ReliableMessaging WS-Acknowledegment WS-Referral WS-Transfer WSXL SOAP MTOM ASAP SOAP Cool! But, What Standards I use? OWL-S WS-Routing WS-Addressing WS-Discovery UDDI WSRP We should integrate our systems using Web Service Technologies WS-Inspection Manager WS-CallBack WS-MessageData WS-Enumeration XKMS WS-NonRepudiation WSCL WS-Federation WS-SecureConversation WS-Trust SAML WS-Security WS-MetadataExchange WS-AtomicTransactions WS-Coordination WS-BusinessActivity WS-Transaction BTP SPML WS-SecurityPolicy XACML WS-Provisioning WSCI WS-PolicyAssertions Too WS-PolicyAttachment many, Overlap, Conflicts, Only few standards are BPEL4WS used WS-Manageability WS-PolicyFramework WS-Topics(WSDL, SOAP) WSCDL WS-Resource WSDM 8 (See ``Interoperability Specifications, May 06, IEEE Computer, by. Motahari, WS-Eventing WS-Notification Benatallah, Casati and Toumani) Boualem Benatallah, 2005

9 Service Oriented Technologies - Layers Discovery UDDI ebxml registry Contracts ebxml CPA Business process BPEL4WS BPML OWL-S service model BPML Transactions WS-Transaction BTP BTP Choreography Conversations Nonfunctional description Service description XML-based messaging WS-Coordination CS-WS WSCL WSEL WSEL WSCI SOAP OWL-S service model OWL-S service profile OWL-S service grounding RDF ebxml BPSS ebxml CPP ebxml messaging Network HTTP, FTP, SMTP, and others WSDL-based Semantic-based ebxml-based 9 Source (Turning Software to a Service, M. Turner et al., IEEE Computer, Vol 36(10), 03) Boualem Benatallah, 2006

10 Systems Integration: B2B Integration Example Private process (Company-specific) Process Receive PO Request Public process (Standard) Send PO Customer Send PO Public process (Standard) Send PO Supplier Receive PO Private process (Company-specific) Process Sales Order Receive PO PO Select Supplier Check Customer Generate RFQ Receive PO Acknowledge Send PO Acknowledge Check Credit CRM Send RFQ Select RFQ Response Receive PO Response Send PO Response Check Availability Create Sales Order SCM Send PO Send PO Response ERP Close Send PO Response Acknowledge Receive PO Response Acknowledge Close (Source: e-business Architectures and Standards, Anil L. Nori, Tutorial, VLDB 2002, HongKong, China) 10

11 Integration Layers Internal system External interactions External interactions Internal system PeopleSoft Content of document Content of document Database Workflow Message definition messages Message definition Workflow Adapter Business rules Business Protocol Business Protocol Business rules Adapter Legacy applications SAP/R3 Programs Policy Policy Programs Business Partner 1 Business Partner 2 Boualem Benatallah,

12 Business Protocol Layer (Cont.) invoke? invoke receive? receive receive invoke Boualem Benatallah,

13 Some Observations on Integration Technologies Great deal at transport protocol level, process-based orchesteraction, programing support for dynamic port binding While standardisation makes interoperability easier, it does not remove the need for data transformation, protocol adaptation Services are designed to be open (possibly no precise knowledge of the various data models and protocols of clients) Data is organized by application, not by following agreed upon conceptual models Standardization of protocols at lower level and languages for higher level abstractions Boualem Benatallah,

14 ServiceMosaic Project: Services LifeCycle Intelligence Modeling of business protocols Algebra for protocol models management Model-driven and aspect-oriented approach to support service adaptation Model-driven change impacts analysis Protocol discovery Query and visualization support for service monitoring, property discovery and verification 14

15 Conversations and business protocols 1:requestQuote customer 2:orderGoods 3:confirmOrder supplier 4:makePayment protocols describe valid ordering of messages stateful interaction this must be done somehow, formally (best) or informally coarse-grained complements interface definition and other specs (semantics) copyright Springer-Verlag,

16 Protocol languages receive requestquote reply requestquote receive ordergoods invoke checkshipavailable invoke cancelorder invoke confirmorder receive makepayment invoke ordershipment receive confirmshipment 16

17 Protocols and choreographies A: Protocol that a service obeys to when interacting with a client B: Protocol that a service obeys to when interacting with its clients Business service C: a choreography D: The protocol that a Business service 17 obeys to when interacting with one or more clients

18 Business Protocols : benefits of explicit representation And they are quite a lot! - service development, management, evolution, binding - Protocol-aware tools can make life easier for developers Boualem Benatallah,

19 Development support top down bottom up Protocol specs Protocol specs protocol compiler protocol generator service skeleton add biz logic service implementation service implementation Boualem Benatallah,

20 Generating composition skeletons customer requestquote ordergoods confirmorder or cancelorder supplier receive requestquote reply requestquote receive ordergoods send cancelorder send confirmorder Boualem Benatallah,

21 Middleware: routing, validation, logging service provider object for P 1 object for P 2 P 1 P 2 logs P 1 service requestor object for P 3 P 3 P 4 conversation controller P 2, P 3 P 4, P 5 service requestor object for P 4 P 5 service requestor object for P 5 protocol defs Avoid implementing exception handling logic Web service concepts, Architectures and Applications. Copyright Springer-Verlag,

22 Static and dynamic binding supplier A customer broker supplier B supplier C Boualem Benatallah,

23 Versioning, evolution, compliance version 1.0 customer version 1.1 XYZ standard specs Boualem Benatallah,

24 Expressive power Services are designed independently of clients Need to be (fairly) fully specified Ordering is not enough. Implicit (timed) activations, timeouts Message content-based conditions, state management hiding details (multiple views) Transactional implications Rightsizing is the key 24

25 Business Protocols Modeling: Embryonic Model Start T1:Login Search book T3:AddToCart() T2:SearchBook() T6:OrderBook() Book selection T4:SearchBook() T11 T5:RemovefromCart() Ordered T8:CancelBookPurchase() Cancelled T7 Shipped T9:ReturnBook() Returned T10 Completed Amazon.com as a Web service Boualem Benatallah,

26 Protocol models management Bring the benefits of abstractions to service-oriented systems developers Analogy with data management: simple model (relational), declarative language (SQL) and algebra Operators to manipulate protocol models (e.g., identifying similarities and differences, identify patterns, identify relationships) Semantics and operators defined based on labeled transition systems 26

27 Protocol models Management (cont.) 27

28 Summary Service oriented computing offers tremendous opportunities for agile and Internet scale integration Business process modeling, web services offer key solutions to virtualization and high level orchestration of business processes Business activity management techniques offer key solutions to business process monitoring and management Effective automation requires an integrated framework that offers lifecycle intelligence! : conceptual modeling, algebra for analysis and manipulation of process views, discovery and debugging, model-driven development of adaptors, simulation, service level-operational level mappings, UI models management and context support for services, Boualem Benatallah,