Software and Systems Engineering Seminar Winter 2011 Domain-specific languages in model-driven software engineering 1 Speaker: Valentin ROBERT

 Research work  Industry use  Tools and standards evaluations  DSL point of view 2

3

 The business process is a series of activities occurring within a company that lead to a specific end. (wisegeek.com)  A workflow consists of a sequence of connected steps. It is a depiction of a sequence of operations, declared as work of a person, a group of persons, an organization of staff, or one or more simple or complex mechanisms. (wikipedia.com) 4

 Identify generic, recurring business process modelling patterns  Unify existing patterns and focus on their expressive power  Language-independent formalism (Coloured Petri-Net) 5

 Formal description of a (business) process  Executable by a workflow management system  In practice: directed bipartite graph of tasks and transitions 6

 Healthcare/Pharmaceuticals  Prescriptions fulfillment, administrative tasks, …  Finance/Banking/Accounting  Error-free accounting, financial accuracy, …  Education  Government/Public Services/Human Resource  Multi-level approval processes  Manufacturing  Six Sigma method  Energy/Utilities  Legal Services/Insurances  IT  Customer Relationship Management 7

8

 1999: Foundation of the Workflow Pattern Initiative ▪ Profesor Wil van der Aalst (Eindhoven University of Technology) ▪ Profesor Arthur ter Hofstede (Queensland University of Technology)  20 first control-flow patterns  Van Der Aalst et al [WP]  Revision of the 20 first + 23 new control-flow patterns  Russell et al [WCFP] 9

 Control-flow patterns  Describes complex workflows (sequence, parallel, multi-threading, mutual exclusion, division and merging, synchronization, …)  Data patterns  Adds data manipulation, internal/external data interaction, data transfer and transformation, data-based routing  Resource patterns  Tasks creation and allocation schemes, detours of a resource in the middle of a task execution, and others…  Exception handling patterns  Work Item Failure, Deadline Expiry, Resource Unavailability, External Trigger, Constraint Violation 10

11 Source: van der Aalst et al., 2003 [WP] Diagram-based DSL

 Control-flow  Basic ▪ Sequence, Parallel, Synchronization, Exclusive Choice, Simple Merge  Advanced branching/synchronization ▪ Multi-choice, Multi-merge, Threads, Discriminators, Partial Joins  Multiple instantiation of activities on triggers  State-based ▪ Deferred Choice, Interleaved Routing, Milestone, Critical Sections  Cancellation, Force Completion, Iteration, Termination, Triggers 12

 Resource  Task creation ▪ Direct, role-based, deferred, capability-based, history-based, …  « Push » task distribution ▪ By offer, random, round-robin, shortest queue, …  « Pull » task distribution  Detour ▪ Delegation, escalation, deallocation, stateful/stateless reallocation, suspension, resumption, skip, redo, pre-do  Auto-start  … 13

 Data  Visibility ▪ Task, block, scope, multiple instance, folder, workflow, environment  Interaction (inside components) ▪ Task to task, to multiple tasks (by reference, by value), from multiple tasks  External Interaction ▪ From environment, to environment  Transfer (between components) ▪ By value, by reference (locked, unlocked)  Data-based routing/triggers 14

 Exceptions  Work Item Failure  Deadline Expiry  Resource Unavailability  External Trigger  Constraint Violation 15

16

XPDL (2.1 - WfMC) BPMN (1.2 – BMI DTF) WS- BPEL (2.0 - OASIS) BPMI? (BMI DTF?) XML Process Definition Language (2002) Business Process Modelling Notation (2004) Business Process Execution Language (2002) Interface (mapping) between XPDL and BPMN (????) 17

18

Manager <NodeGraphicsInfo LaneId="1" ToolId="Interstage BPM » IsVisible="true" Page="1"> […] XML file Also contains meta-data Reference: [XPDLEx] 19 Goal: exchange format for models of workflow products

<partnerLink name="printService" partnerLinkType="print:printLink" partnerRole="printService"/> <variablename="hello_world" messageType="print:PrintMessage" /> Hello World $hello_world.value <invokepartnerLink="printService"operation="print" inputVariable="hello_world" /> 20 Programming logic - BPEL Data types - XSD Input/Output (I/O) - WSDL Reference: [BPELEx]

 Partner Links / Endpoints  Identifies parties you interact with  Variables  Data container (XSD value or WSDL message)  Assignments  Invocations  Invokes a web-service endpoint 21

22

STRENGHTS  Designed to be flexible  Seems to support much of the Workflow Patterns  The new version should add semantics and interoperability (via a standard meta-model) WEAKNESSES  Providing flexibility implies no formal execution semantics (?) 23

STRENGHTS  Current mainstream interchange standard  Supports human workflows WEAKNESSES  Lacks formal execution semantics (transactions, faults, …)  Not flexible enough to successfully cover BPMN (and BPMN vendor-specific extensions)  Ambiguous interpretations of the standard  Only partial mapping to BPEL (missing contructs + ambiguities) 24

STRENGHTS  Industry-accepted standard for SOA (Oracle, IBM, Microsoft, SAP, BEA, Fuego, Lombardi, …)  Designed specifically for business processes (interacting through web- services) WEAKNESSES  Does not support human workflows and user interactions (in a standard way) -> BPEL4People and WS-HumanTask (role- based human tasks)  No standard modeling notation (BPMN bindings) 25

 Much debate around their unification  BPMN is more businessperson-friendly, BPEL requires more knowledge, someone would lose something.  Keeping the same model during the whole process (modeling + execution) would be good, but…  … separating them allows the model to evolve while it is being executed with no issue (hot process migration?).  The same BPMN model will produce different BPEL behaviors depending on the vendor interpretation. 26

27 Reference: [Interop]

28 Reference: Wohed et al [BPM2BPMN] + direct support+/- partial support- lack of support

29 Reference: Wohed et al [BPM2BPMN]

30 Reference: Wohed et al [BPM2BPMN]

ToolBPMN support XPDL support WS-BPEL support CommercialOpen Source Adobe LiveCycleXXXX Appian EnterpriseXXXX Bonita & OrchestraXXXX Enhydra SharkXXXX Fujitsu Interstage BPMXXXX Global 360 BOSXX?X IBM FileNet BPMXXXX IntalioXXX Oracle BEAXXXX Lombardi BluePrintXXXX ProcessMakerXX-X 31

 XPDL implementations: ADVANTYS WorkflowGen, Amazonas Workflow, Arachnea EverSuite, Appian Enterprise, Ascentn AgilePoint Server, Aspose'sAspose.Workflow, Assetlink Corporation, BOC ADONIS, BEA Systems, Brein VB's InProces, Bonita, ProEd Workflow Editor, Canto CanFlow, CapeVisions, CHALEX BPM Framework, ComActivity, Cordys BPMS, COSA Designer, Cubetto Toolset, Eclaire Group LynxFlow Designer, EMC Documentum ApplicationXtender Workflow, EMC Documentum Process Suite, Enhydra Shark, Enhydra JaWE, First Trace’s Kinnosa Workflow, FinantixStudio FXS, Fujitsu Interstage BPM (i-Flow), FileNet Business Process Manager, Global 360 Business Optimzation Server (BOS), HOGA.PL'S intraDok, IBM FileNet Business Process Manager, IDS Scheer Business Architect, iGrafx, Interwoven WorkRoute MP, Infinity Process Engine, Infor (formerly SSA Global), ITP-Commerce Design, jawFlow, Jenz & Partner's BPEdit, KAISHA-Tec's ActiveModeler Avantage, Lombardi's Blueprint, Metoda S.p.A OpenMet BPMF, Mono-sys's Tigris BPM, Nautica, Open Business Engine, OpenPages Governance Platform, Openwork, Oracle 9i Warehouse Builder, Pentaho's B1 Platform, Projekty Bankowe Polsoft's BPB Workflow, proLOGIT BPR Business Process Reporter, QualiWare, R-Data's E-SOD, Rodan Systems OfficeObjects Workflow, Savvion, Simprocess from CACI, Software AG's Crossvision BPM, SpeechCycle's LevelOne virtual CSR platform, TIBCO iProcess Suite, Together Workflow Editor, Transware Ambassador, Unisys, Vignette Process Workflow Modeler, W4's W4 BPM Suite, WfMOpen, Workflow::Wfmc, Zynium's Byzio  BPEL engines: ActiveVOS, Apache ODE, BizTalk Server, iBolt Server, jBPM, Open ESB, Oracle BPEL Process Manager, OW2 Orchestra, Parasoft BPEL Maestro, Petals BEPL Engine, SAP Exchange Infrastructure, Virtuoso Universal Server, Websphere Process Server 32

 Yet Another Workflow Language  By the « Workflow Patterns » team  YAWL vs. (WS-)BEPL  BPEL is an industry standard, YAWL has only one implementation.  Both have static analysis tools (based on Petri nets, Process Algebra, Finite State Machine).  YAWL provides support for human tasks.  YAWL supports all Workflow Patterns. (BEPL 2.0 reduces the gap) 33

34

 Three DSLs maintained by three organisms, with three goals (sometimes overlapping)  Serialization and interoperability issues  Expressiveness issues (vendors extend the standards, impossibility of full interoperability)  Domain Specific Meta-Language for domain concepts? (Business Process Definition Metamodel, by the OMG)  Target issues (businessperson-friendly WYSIWYG solutions vs. IT savvy flexibility) 35

36

[BPELEx] Antony Miguel. WS-BPEL 2.0 Tutorial. Tutorial – Basic BPEL [BPM2BPMN] P. Wohed, W. M. P. van der Aalst, M. Dumas, A.H.M. ter Hofstede, and N. Russell. On the Suitability of BPMN for Business Process Modelling. In Proceedings 4th International Conference on Business Process Management (BPM 2006), LNCS [BPMN2BPEL] Chun Ouyang, Marlon Dumas, Arthur H. M. ter Hofstede, and Wil M. P. van der Aalst From BPMN Process Models to BPEL Web Services. In Proceedings of the IEEE International Conference on Web Services (ICWS '06). IEEE Computer Society, Washington, DC, USA, DOI= /ICWS [Interop] Keith Swenson. Collaborative Planning & Social Business. The BPMN-XPDL-BPEL value chain [WCFP] N. Russell, A.H.M. ter Hofstede, W.M.P. van der Aalst, and N. Mulyar. Workflow Control-Flow Patterns: A Revised View. BPM Center Report BPM-06-22, BPMcenter.org, 2006.Workflow Control-Flow Patterns: A Revised View 37

[WDP] N. Russell, A.H.M. ter Hofstede, D. Edmond, and W.M.P. van der Aalst. Workflow Data Patterns. QUT Technical report, FIT-TR , Queensland University of Technology, Brisbane, 2004.Workflow Data Patterns [WP] W. M. P. van der Aalst, A. H. M. ter Hofstede, B. Kiepuszewski, and A. P. Barros Workflow Patterns. Distrib. Parallel Databases 14, 1 (July 2003), DOI= /A: [WRP] N. Russell, A.H.M. ter Hofstede, D. Edmond, and W.M.P. van der Aalst. Workflow Resource Patterns. BETA Working Paper Series, WP 127, Eindhoven University of Technology, Eindhoven, 2004.Workflow Resource Patterns [XPDLEx] Keith Swenson. XPDL.org. XPDL BPMN Example [YAWL] W. M. P. van der Aalst and A. H. M. ter Hofstede YAWL: yet another workflow language.Inf. Syst. 30, 4 (June 2005), DOI= /j.is