ActiveVOS - Server Architecture March 2009

2 Topics ActiveVOS - Server Architecture – Core Engine, Managers, Expression Languages – BPEL4People People Activity WS-HT Human Tasks – Deployment – Services – Administration ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

3 ActiveVOS Architecture Overview Core ActiveVOS Engine – Process Definition, validation and execution WS-BPEL 2.0 and BPEL4WS 1.1 compliant BPEL4People – Extensible Expression Execution XPath 1.0, XQuery (XPath 2.0), JavaScript,... Server Engine Managers – Alarm Manager – Cluster Manager – Deployment Manager – Process Manager – Queue Manager – Storage Manager – Task Manager – Complex Event Processing Service framework – Policy driven – Publishes endpoints which Receive and Reply to callers in conjunction with engine – Invokes of endpoints – Publishes administrative, WS-HT APIs – Robust interface allows wide variety of service types. WS, JMS, POJO, REST... Utilities and Other Services – Work and Timer Managers – URN Mapping – Identity Services – Services Deployment Handling Administration

4 ActiveVOS Server ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

5 ActiveVOS Server ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

6 Core ActiveVOS BPEL Engine Factory creates engine with appropriate configuration – Engine Configuration – points to managers, expression languages, function extensions and specific processing directives – Configuration loaded from an XML file called aeEngineConfig.xml by default or can be passed to factory Managers perform operations on behalf of engine Manages failover and inter-engine facilitiesCluster Manager Manages timers for on alarms and waitsAlarm Manager Manages interaction with persistent storageStorage Manager Manages Receive Queues and correlationsQueue Manager Creates Process and Manages Process State saving and restoration Process Manager Manages human tasksTask Manager

7 Process BPEL Process Definitions – Installed into the engine via a standardized deployment format (or directly through API)‏ – Utilize a visitor pattern on the definition objects for creation of implementation classes – Cached as part of overall deployment plan for process Process Implementations – Handle activity execution scheduling and event notifications – Are themselves derived from the scope activity Visitors and definitions can be extended for custom activities – BPEL4People implementation is an example of a extension

8 Activities Activity Implementations are associated with definition objects at construction All activities have a state, and transition through one or more standard states – Inactive, Ready to Execute, Executing, Finished, Faulted and Dead Path – State changes trigger events which can have registered listeners – Activity state is key to depicting proper visualizations of process – ActiveVOS consoles and debuggers depict state visually Each activity has an execute method to do the actual execution – Activities set object completed state when their work is done, not always when execute is complete (some work can be asynchronous from actual execute – e.g. Receive)‏

9 ActiveVOS Server – Expression Processing ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

10 Expression Processing Engine Configuration allows installation of multiple Expression Languages – Expression languages are registered with a namespace, which is used in the BPEL process to designate the language to use – Expression languages support both analysis and runtime execution – All expression languages can support custom function contexts Registration is by namespace and associates those entries with a function context Once a context is registered it can be used in any BPEL process Built in support for XPath, XQuery and JavaScript – XPath is supported via JAXEN – XQuery is supported through SAXEN – JavaScript is supported through Rhino Also has support for BSF – An example is provided for Python

11 Example: Custom function integration Evaluate XPATH Expression with Custom Function ActiveVOS Engine Runtime Environment User defined Custom Functions ActiveVOS BPEL Engine BPEL Process Custom Function Evaluation Flow XPATH Language Environment Expression Language Factory XQUERY Language Environment JAVA SCRIPT Language Environment Evaluate Custom Function BPEL Function Context Function Context Factory Custom Function Context Expression Evaluation Function Evaluation Entity Instantiation

12 ActiveVOS Server – BPEL4People ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

13 BPEL4People (B4P) – WS-BPEL Extension for People – Integrates human tasks into BPEL processes – Defines a new activity (People Activity) which invokes a WS-HT task service – Tasks can be defined Locally in the BPEL process Outside of the BPEL process, allowing them to be shared by more than one process Web Services Human Task (WS-HT) – Integrates human tasks into service-oriented applications – Human tasks are services ‘implemented’ by people – Specifies a human task schema definition – Defines an API for manipulating tasks (task inbox)‏ BPEL4People

14 BPEL4People - Task Management Task Management Environment – Performs task state and lifecycle processing (deadlines, escalation)‏ Handles notifications triggered by escalations Lifecycle handling built as BPEL processes – Enforces role operations, who can do what and when Uses integrated identity services Providers supplied for LDAP, LDIF and XML Easy addition of custom providers – Exposes services layer for interacting with tasks Standard Robust WS-HT API Task information contains rendering information provided by developer for generalizing integrations ActiveVOS Inbox uses WS-HT API (task list client)‏

15 Built-in Task Inbox Application Inbox Application – Web application which uses WS-HT for presenting tasks to users – Task lists Filters (claimed, started, …)‏ – Custom sorting Actions to claim, and start work in list – Task Detail Built-in complete task detail handling – Owners and administrators can claim, start, revoke, forward, complete and fault tasks Attachment and comment support Customizable either whole page or work item via XSL Can be used as a starting point for more complex task inbox – WS-HT allows for a rich set of rendering capabilities

16 ActiveVOS Server – Deployment ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

17 Deployment Business Process Archive (*.BPR file)‏ – Contains processes and process deployment descriptors as well as resources like WSDL, Schema and Style Sheets Process Deployment Descriptor – Describes Partner Link associations and policies My Role – Service information for installing process endpoints – Service Name, Allowable Roles, Binding and Policies – BPEL4People - Logical People Group Assignment Maps logical people groups to users or groups – Process Specific directives Persistence (None, Full, …),suspend on uncaught fault, data indexes, … Partner RoleEndpoint References StaticDefined in deployment descriptor DynamicMapped in Process (i.e. assign to partnerRole)‏ InvokeTransmitted in SOAP headers of Partner (WS-Addressing)‏ PrincipalLookup from Partner Definition based on Authenticated Principal

18 Deployment Multiple deployment interfaces – Administrative console page for uploading a BPR – Web service for accepting a BPR – Directory scanner for looking for new, modified or removed deployments – Direct Administrative API call can be used for custom deployment High availability and clustering Application Servers: Red Hat JBoss Enterprise Application Platform 4.3 Red Hat JBoss Enterprise SOA Platform 4.3 Apache Tomcat 5.x BEA WebLogic Server 9.2 Oracle WebLogic 10.3 IBM WebSphere Server 6.1 Database Servers: MySQL 5.x, Oracle Database 10g, Microsoft SQL Server 2005, IBM DB2 8.x, 9.x

19 ActiveVOS Server – Services and Administration ProcessActivity Common Utilities: Timer, Work, URN Mapping URN Mapping Process Creation & Management ActiveVOS BPEL Engine Admin and Event Admin and Event Handling Handling Deployment Plans Deployment Plans Process State Process State Queues and Alarms PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers Web/Application Server Queues TaskManagement Alarms ManagersExpression Processing Processing MUWS Other Services JMS, REST, POJO,... Directory Services Inbox Alerts,ExceptionManagement

20 Service Layer  Exposes key runtime interfaces  Process endpoints (“My Role” deployments)‏  Administrative API:  Engine Admin, MUWS, Event Listeners  WS-HT API  Receive and Invoke Handlers are pluggable  Web service support implemented using Axis  WS-Addressing  WS-Security  WS-Reliable Messaging  POJO – plain old java objects  JMS Support  REST Support  EJB  Policy driven – transports and capabilities are driven by policy attachments  Partner Addressing supports partner lookups (e.g. By principal)‏ Admin and Event Admin and Event Handling Handling PolicyManagement PartnerAddressing Web Services Receive and Invoke Handlers MUWS Other Services JMS, REST, POJO,...

21 Service Handler Factories ActiveVOS Service Engine Architecture Entity Instantiation Outbound Service Invoke Flow Inbound Service Request Flow ActiveVOS BPEL Engine BPEL Process WS Receive Handler WS Receive Handler JMS Receive Handler JMS Receive Handler... Receive Handler... Receive Handler REST Receive Handler REST Receive Handler Receive Handler Factory Receive Handler WS Invoke Handler WS Invoke Handler Process Invoke Handler JMS Invoke Handler JMS Invoke Handler POJO Invoke Handler POJO Invoke Handler Invocation Handler REST Invoke Handler REST Invoke Handler... Invoke Handler... Invoke Handler Invoke Handler Factory Receive and invoke handler factory architecture allows for extensible service framework

22 Simplified Request Dispatch Flow Partner Addressing Receive Handler Lookup Correlated Receive Deployment Plan QueuedReceives Not Found Found Create? No Fault Yes New Process Dispatch Receive To Process And Queue Reply Process Reply Activity Receive Activity Queued Reply WebServiceRequestWebServiceRequest Queue Manager

23 Administrative API Allows process maintenance interactions – Suspend, Resume, Terminate, Process State Request, Process List, etc. – Registers process and engine event listeners Can also dispatch events to Web services Interfaces – Available directly through engine factory for in-process usage – Most methods are also exposed via a Web service, which will be the recommended interface – OASIS WSDM/MUWS API usage examples – Consoling, debugging, external management,...

24 Administration - Process Exception Management Process Exception Management – Some critical processes can’t be allowed to fail because of programming or environmental errors – Developers and Administrators need to be able to take corrective action to ensure process success ActiveVOS - Process Exception Management – Allows suspending processes on uncaught faults Configurable at per process level with an engine default – Integrates an alerting service so that appropriate actions can be taken – Set of robust API for fixing a problem (changing data, retrying activities and scopes, coercing an activity into completing normally)‏ – Administrative Consoling for manually fixing a problem – Easy filtering of processes in a suspended/faulting state

25 Conclusion ActiveVOS is built on a world class architecture and components Robust BPEL engine – Utilizes Managers for flexible implementation of surrounding functionality Extensible expression language integration with custom functions BPEL4People extension for standardized workflow Deployment considers many scenarios for binding and process directives Service handling delivers ease of service creation and interfacing Policy driven architecture for proper process governance Rich administrative functionality – Process exception management handles unexpected faults – Alerting and monitoring facilitates enterprise management