Business Process Execution Language for Web Services

Transcription

1 Business Process Execution Language for Web Services Second Edition An architect and developer's guide to orchestrating web services using BPEL4WS Matjaz B. Juric With Benny Mathew and Poornachandra Sarang BIRMINGHAM - MUMBAI

2 Preface Chapter 1: Introduction to BPEL and SOA Why Business Processes Matter 5 Automation of Business Processes 6 Exposing and Accessing the Functionality of Applications as Services 7 Enterprise Bus Infrastructure for Communication and Management of Services 7 Integration between Services and Applications 7 Composition of Exposed Services into Business Processes 7 Web Services 8 How Web Services Differ from their Predecessors 9 Web Services Technology Stack 9 Enterprise Service Bus 10 ESB Features 11 Service Oriented Architecture 12 SOA Concepts 12 Services 13 Interfaces 13 Messages 13 Synchronicity 13 Loose Coupling 14 Registries 14 Quality of Service 14 Composition of Services into Business Processes 14 Service Composition 16 BPEL for Service Composition 17 BPEL Features 18 Orchestration and Choreography 19 Executable and Abstract Processes 21 Relation of BPEL to Other Languages 22 ebxml BPSS 22 BPML 23 WSCI 24 WS-CDL 24

3 BPEL Servers Overview 25 Oracle BPEL Process Manager 27 Microsoft BizTalk 27 IBM WebSphere Business Integration Server Foundation 27 IBM BPWS4J 28 ActiveBPEL Engine and ActiveWebflow 28 OpenStorm Service Orchestrator 29 The Future of BPEL 29 Conclusion 30 Chapter 2: Web Services Technology Stack 31 E-Business Collaborations 31 WS-Security 34 Example 34 Binary Security Token 35 Referencing an External Security Token 35 Faults 36 Typical Business Transaction Scenario 36 WS-Coordination 37 The Framework 38 Scenario 38 CoordinationContext 40 CreateCoordinationContext 40 CreateCoordinationContextResponse 41 Register 41 RegisterResponse 41 Faults 41 Web Services Transaction Specifications 42 Atomic Transaction 42 Sharing Context Information 42 Coordination Protocols 43 Business Activity 44 Sharing the Context Information 45 Coordination Protocols 45 OASIS BTP 46 The BTP Stack 48 The BTP Model 48 Atomic Transactions 49 Cohesive Transactions 49

4 Reliable Messaging 49 Messaging Model 50 Example 51 Requesting Acknowledgement 51 Delivery Assurances 51 Other Assertions 52 Faults 52 WS-Addressing 53 Endpoint Reference 53 Faults 55 WS-lnspection 55 Inspection Document Hierarchy 56 WS-Policy 56 Policy Outline 57 The <wsp:aii> Operator 57 The <wsp:exactlyone> Operator 57 The <wsp:oneormore> Operator 57 The <wsp:policy> Operator 57 Policy Assertions 57 Example 58 Policy Inclusion 58 WS-Eventing 59 Event Subscription 59 Response to Event Subscription 60 Subscription Renewal 61 Unsubscribing 61 Subscription End Message 62 Conclusion 63 Chapter 3: Service Composition with BPEL 65 Developing Business Processes with BPEL 65 Core Concepts 67 Invoking Web Services 70 Invoking Asynchronous Web Services 71 Synchronous/Asynchronous Business Processes 72 Understanding Links to Partners 73 Partner Link Types 75 Defining Partner Links 77 BPEL Process Tag 78

5 Variables Providing the Interface to BPEL Processes: <invoke>, <receive>, and <reply> Assignments Conditions BPEL Business Process Example Involved Web Services Employee Travel Status Web Service Airline Web Service WSDL for the BPEL Process Partner Link Types Business Process Definition BPEL Process Outline Partner Links Variables BPEL Process Main Body Asynchronous BPEL Example Modify the BPEL Process WSDL Modify Partner Link Types Modify the BPEL Process Definition Conclusion Chapter 4: Advanced BPEL Advanced Activities 108 Activity Names 108 Loops 108 Delays 110 Deadline and Duration Expressions 110 Empty Activities 111 Process Termination 112 Fault Handling and Signaling 112 WSDL Faults 112 Signaling Faults 113 Signaling Faults to Clients in Synchronous Replies 114 Signaling Faults to Clients in Asynchronous Scenarios 115 Handling Faults 117 Selection of a Fault Handler 118 Synchronous Example 119 Asynchronous Example 121 Inline Fault Handling

6 Table of Scopes 123 Example 125 First Scope 127 Second Scope 129 Third Scope 131 Serializable Scopes 132 Compensation 132 Compensation Handlers 133 Example 135 Invoking Compensation Handlers 136 Managing Events 137 Pick Activity 138 Message Events 138 Alarm Events 139 Example 139 Event Handlers 140 Example 142 Business Process Lifecycle 143 Correlation and Message Properties 145 Message Properties 145 Mapping Properties to Messages 146 Extracting Properties 147 Properties and Assignments 147 Correlation Sets 148 Using Correlation Sets 149 Concurrent Activities and Links 150 Sources and Targets 151 Example 151 Transition Conditions 157 Join Conditions and Link Status 158 Join Failures 159 Suppressing Join Failures 160 Dynamic Partner Links 161 Abstract Business Processes 162 Model Driven Approach: Generating BPEL from UML Activity Diagrams 164 Conclusion

7 Chapter 5: Oracle BPEL Process Manager and BPEL Designer: Overview 167 Overview and Architecture 167 BPEL Server 169 Core BPEL Engine 169 WSDL Bindings 169 Integration Services 170 BPEL Console 170 BPEL Designer 171 Database 171 Process Deployment Example 171 Process Descriptor 172 Configuration Properties 174 Setting the Environment 175 BPEL Compiler and Revision Numbers 176 Deployment and Domains 177 Ant Utility 177 Process Management with the BPEL Console 178 Visual Flow 181 Instance Auditing 182 Debugging 182 Overview of Other BPEL Console Functions 184 Deploying Processes 186 Management 187 Performance Tuning 188 Domains and Administration 190 Administration of Server-Related Parameters 191 Managing BPEL Domains 192 Graphical Development with BPEL Designer 193 JDeveloper BPEL Designer 194 Importing Existing BPEL Processes 195 Partner Links and Web Services 195 Variables 196 Process Activities 198 Copy Rule Editor 199 XPath Expression Builder 200 XSLT Mapper 201 BPEL Validation Browser 203 Building and Deploying 204 Eclipse BPEL Designer 206 Partner Links and Web Services 207

8 Variables 208 XML Type Browser 209 Process Map 210 Copy Rule Editor 211 Function Wizard 211 Building and Deploying 212 Summary 213 Chapter 6: Oracle BPEL Process Manager: Advanced Features 215 Extension Functions and Activities 215 Transformation and Query Support 217 Data and Array Manipulation 218 XML Manipulation 220 Date and Time Expressions 220 Process Identification 221 LDAP Access and User Management 221 Dynamic Parallel Flow 222 Dynamic Flow Example 223 Providing a List of Partner Links 224 Dynamic Parallel Invocation of Airline Services 224 Dynamic Partner Links 225 Offer Selection Loop 226 Deploying and Testing the Example 227 Web Services Invocation Framework 228 Advantages of WSIF 229 Java to XML Bindings 230 XML Facades 231 Invoking a Java Class through WSIF 233 Defining WSIF Bindings in WSDL 233 WSIF Bindings for Java Classes 234 Testing the Example 235 Exception Handling 237 User Exceptions in Java 238 Defining Faults in WSDL 238 Defining WSIF Binding for an Exception 239 Custom Exception Serializers 241 Invoking EJB through WSIF 243 WSDL for Session Bean 244 WSIF Binding for EJB 245 Generating WSIF Bindings from JDeveloper 247

9 Java Code Embedding 249 Invoking a Java Class from Embedded Code 250 Notification Service 253 Example 254 Notification Wizard 255 Review of Code 258 Testing the Example 258 Mail and JMS Services 259 Workflow Service 259 Workflow Patterns 260 Example 261 Checking User Outcome 267 Worklist Application to Approve Ticket 268 Identity Service 271 BPEL Server APIs 273 Summary 274 Chapter 7: MS BizTalk Server 275 Overview 275 Support for BPEL and XLANG/s 276 Architecture 276 Ports 277 Receive Locations 278 Adapters 278 Receive Pipelines 279 Message Contexts 280 Promoted Properties 280 Distinguished Fields 280 The MessageBox 281 How Publish-Subscribe works 281 Orchestrations 281 Maps 282 Business Rules Engine 283 Send Pipeline 283 Building a Sample Orchestration in BizTalk 284 Scenario 284 Implementation 285 Exporting Orchestration to BPEL 291 Importing BPEL Processes into BizTalk 294

10 Do's and Don'ts for BPEL Compliance in BizTalk 305 Comparing BizTalk Orchestration Constructs with BPEL 306 Receive and Send Shapes (<receive>, <invoke>, <reply>) 307 Port and Role Link Shapes (<partnerlink>, <partnerlinktype>, <role>) 307 Expression and Message Assignment Shapes (<assign>, <copy>, <from>, <to>) 308 Decide Shape (<switch>, <case>, <otherwise>) 309 Delay Shape (<wait>) 310 Parallel Actions Shape (<flow>) 310 Loop Shape (<while>) 311 Suspend Shape 311 Terminate Shape (<terminate>) 311 Advanced BPEL Functions using BizTalk 312 Listen Shape (<pick>, <onmessage>, <onalarm>) 312 Scope Shape (<scope>) 313 Throw Exception Shape and Exception Handling (<throw>, <faulthandler>, <catch>, <catchaii>) 314 Compensate Shape and Compensation Block (<compensate>, <compensationhandler>) 315 Correlation (<correlations>, <correlationsets>) 316 Other BizTalk-Specific Features 316 Integration with other BizTalk Servers 316 Integration with Web Services 317 Integration with the.net Framework 317 Human Workflow Services (HWS) 317 Business Activity Monitoring (BAM) 318 Health and Activity Tracking (HAT) 318 BizTalk Server 2006 and Beyond 318 Summary 319 Appendix A: BPEL Syntax Reference 321 Important BPEL Activities and Elements 321 <assign>, <copy>, <from>, <to> 321 <catch>, <catchaii> 322 <compensate> 323 <compensationhandler> 324 <correlations>, <correlation> 325 <correlationsets>, <correlationset> 325 <empty> 325 <eventhandlers> 326

11 <faulthandlers>, <faulthandler> 326 <flow> 327 <invoke> 328 <links>, <link> 329 <onalarm> 329 <onmessage> 330 <partnerlinks>, <partnerlink> 330 <partneii_inktype>, <role> 330 <partners> 331 <pick> 331 <process> 332 <property> 333 <propertyalias> 333 <receive> 334 <reply> 334 <scope> 334 <sequence> 335 <source> 335 <switch>, <case> 336 <target> 337 <terminate> 337 <throw> 337 <variables>, <variable> 338 <wait> 338 <while> 338 BPEL Functions 339 getlinkstatuso 339 getvariabledata() 340 getvariablepropertyo 340 Deadline and Duration Expressions 340 Standard Elements 341 Standard Attributes 341 Default Values of Attributes 342 Standard Faults 342 Namespaces 343 Index 345