[jboss-user] [jBPM] - jBPM3 Design Documentation

Administrator Administrator [http://community.jboss.org/people/admin] modified the document: "jBPM3 Design Documentation" To view the document, visit: http://community.jboss.org/docs/DOC-15934 -------------------------------------------------------------- The purpose of this article is to gather design documents and diagrams together. *** #Design_Diagrams Design Diagrams **** #Product_Components Product Components **** #Process_definition_and_instance Process definition and instance **** #Node_hierarchy Node hierarchy **** #Asynchronous_node Asynchronous node **** #Timer Timer *** #Project_Modules Project Modules *** #Tooling_Interfaces Tooling Interfaces **** #Graphical_process_designer Graphical process designer **** #Web_console Web console *** #Database Database **** #Compatibility Compatibility **** #Schema Schema ***** #Definition_data Definition data ***** #Execution_data Execution data *** #API_Usage API Usage **** #Starting_a_process_instance Starting a process instance **** #Signaling_a_token Signaling a token **** #Retrieving_a_task_list Retrieving a task list *** #Test_Coverage Test Coverage **** #Continuous_integration Continuous integration **** #Areas_of_attention Areas of attention h3. Design Diagrams h4. Product Components http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9952... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Process definition and instance http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9971... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Node hierarchy http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9973... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Asynchronous node http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9974... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Timer http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9972... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h3. Project Modules || Module || Description || | core | Process engine codebase and the project test suite. | | db | Database  schema  scripts for every version (since 3.2.2), plus the scripts to  generate the new jBPM DB schema scripts for every new version when it is  being released. | | distribution | Product  installer. The idea was that this installer  would be the interface  between the project and the product. Instead, the SOA platform build  does an automated installation and then a script cherry picks files from  the installation. | | enterprise | Message and  scheduler services based on JMS and EJB timers respectively.  Those  services are not used in the product.   Instead, the JCA inflow services  are used. | | examples | Sample processes that ship with the product. | | identity | Identity component containing the classes for users, groups and memberships. | | simulation | Process analysis and optimization tool donated by Camunda GmbH (http://www.camunda.com/). Not part of the product. | | userguide | User  guide in the docbook format.  Note that these docs are decoupled from  the product  docs.  Changes must be propagated to the docs team  separately. | h3. h3. Tooling Interfaces h4. Graphical process designer GPD depends on the file src/main/etc/version.info.xml in the distribution module. This file contains the locations of the jar files that are needed to create a new project. The tooling expects the following folder layout: || Directory || Contents || | lib | binaries and dependencies | | src | source jars | | config | configuration resources | | examples | sample processes | For deployment, a servlet that accepts process archives with file upload has to be configured.  This features was only added for usage during development.  So after we found out that this imposed a security problem, then we proposed to remove the servlet.  But the latest product decision was to secure the servlet. h4. Web console The console just uses the jBPM 3 API and libraries directly and it should be configured to connect to a data source. h3. Database h4. Compatibility jBPM uses Hibernate as ORM framework. This means that, theoretically, jBPM is compatible with any Hibernate-compatible database (ie any database for which there exists a Hibernate dialect). However, extensive compatibility testing is done on the databases which are listed as certified databases for the SOA-P (and more). jBPM is continuously evaluated with the relational database systems listed in http://community.jboss.org/docs/DOC-13763 jBPM3 Platform Support. h4. Schema The following sections will discuss the jBPM schema. Refer to http://community.jboss.org/docs/DOC-11086 Jbpm31DataModel for diagrams of the definition and execution data models. h5. Definition data * JBPM_PROCESSDEFINITION: general process definition data (name, description, etc). * JBPM_NODE: data about one node in the process definition. All node types will store common data in this table. * JBPM_TRANSITION: every record in this table represents one transition between two nodes of the process definition. * JBPM_EVENT: static data about events that are triggered during process execution. * JBPM_ACTION: user code related to the process definition. * JBPM_DELEGATION: information about user code that uses delegation classes. * JBPM_EXCEPTIONHANDLER: information about exception handlers attached to certain process definition scopes. Relates to JBPM_ACTION for the actual delegation to custom Java exception handlers. * JBPM_VARIABLEACCESS: stores the read/write and mapping information for variables when variables are passed to for example subprocesses. * JBPM_TASK: contains static information about tasks: task name, properties (blocking, duedate, etc.), assignee expression. * JBPM_MODULEDEFINITION: generic table that stores for example (a part of) a task definition, a process definition start task, etc. * JBPM_SWIMLANE: static description of a task swimlane. Contains an expression or a reference to a delegation class for the actual assignment at runtime. * JBPM_TASKCONTROLLER: Stores the reference to a user code delegation class that implements task controller functionality. * JBPM_ID_USER/GROUP/MEMBERSHIP: user/group data for the default identity component h5. Execution data * JBPM_PROCESSINSTANCE: general data about an execution of a process definition. * JBPM_TOKEN: stores the actual pointers that indicate the current state of a process instance. The jBPM model is based on a hierarchical tree of tokens. The JBPM_PROCESSINSTANCE table refers to a so-called 'root-token' that is created when the process instance is created. The tree of tokens can be constructed using this token-rootToken-processInstance relationship. * JBPM_VARIABLEINSTANCE: runtime data in the form of process variables are stored in this table. Multiple columns such as 'datevalue_', 'longvalue_', 'stringvalue_', etc are used to store the actual variables depending on the variable types. * JBPM_BYTEARRAY/JBPM_BYTEBLOCK: tables used to store binary data (eg binary variables). * JBPM_SWIMLANEINSTANCE: contains runtime evaluations of assignment expressions/delegations. * JBPM_TASKINSTANCE: runtime tasks (ie with a runtime actor and token reference). * JBPM_POOLEDACTOR/JBPM_TASKACTORPOOL: when task assignment expressions resolve to a group of actors (a so-called 'pool of actors'), the runtime evaluations are stored in these two tables. * JBPM_JOB: stores runtime job information that is used to execute jobs, and in particular asynchronous continuations of process logic, by the job executor. * JBPM_TIMER: timers are a specific type of jobs that are executable by the jBPM job executor. However, timers need additional information such as 'transitionName' (transition taken when te timer fires), the task to which the timer is attached to, etc. All this extra runtime information is stored in this table. * JBPM_LOG: generic table that contains all historical/audit data generated by the jBPM engine. This table has quite some columns to store the different types of historical events. At runtime, this table can get seriously big, and maintenance scripts should be developed to keep performance decent. h3. API Usage h4. Starting a process instance http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9968... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Signaling a token http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9969... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h4. Retrieving a task list http://community.jboss.org/servlet/JiveServlet/showImage/102-15934-3-9970... http://community.jboss.org/servlet/JiveServlet/downloadImage/102-15934-3-... h3. Test Coverage h4. Continuous integration The project leverages the http://http://hudson.jboss.org/hudson/view/jBPM/ Hudson installation maintained by JBoss QA. The codebase also provides scripts and configuration files to set up a local Hudson server useful for troubleshooting purposes. Visit http://community.jboss.org/docs/DOC-12865 jBPM3 Hudson Setup for a step-by-step guide. h4. Areas of attention A significant amount of research is necessary to explore this path.  One direction we've been thinking about is using the java debugger capabilities to achieve this.  In that case, the unit test could pretend to be a debugging tool that puts breakpoints and steers the execution in a controlled fashion to optimistic locking exceptions. -------------------------------------------------------------- Comment by going to Community [http://community.jboss.org/docs/DOC-15934] Create a new document in jBPM at Community [http://community.jboss.org/choose-container!input.jspa?contentType=102&am...]