Agent Workflows with WADE
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Mini-tutorial presenting: The workflow metaphor Agent-based workflows WADE Framework Overview WADE Architecture Case study
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Agent Workflows with WADE
- 1. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Agent Workflows with WADE Márcio Fuckner1 1Université de Technologie de Compiègne, France Multiagent System Development
- 2. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Outline 1 The workflow metaphor 2 Agent-based workflows 3 WADE Overview Architecture 4 The Factorial case study Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows
- 3. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Definition Workflow A workflow is the automation of a business process, which artifacts, information and/or tasks are passed from one actor to another according to a set of procedural rules. [Workflow Management Coalition, 2013]
- 4. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Definition Workflow A workflow is the automation of a business process, which artifacts, information and/or tasks are passed from one actor to another according to a set of procedural rules. [Workflow Management Coalition, 2013] Formalisms Many formalisms exist to represent a workflow. Some examples are flow charts, UML activity diagrams and finite state machine diagrams.
- 5. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows A workflow example
- 6. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Functional Areas Figure: Source: [Caire, 2008]
- 7. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Examples of Workflow Description Languages BPEL Business Process Execution Language. • Keywords: SOA, WS oriented • More information: OASIS (http://www.oasis-open.org) XPDL XML Process Definition Language. • Keywords: Visual modelling notations, XML based • More information: Workflow Management Coalition (http://www.wfmc.org)
- 8. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Pros and Cons
- 9. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Pros and Cons Pros • Extremely intuitive. Can be validated by domain experts with no programming skills • Self-documented • Execution steps are made explicit • Workflows are interpreted at runtime • Several infrastructure facilities
- 10. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Pros and Cons Pros • Extremely intuitive. Can be validated by domain experts with no programming skills • Self-documented • Execution steps are made explicit • Workflows are interpreted at runtime • Several infrastructure facilities Cons • Not suitable to deal with low-level operations • Supporting tools not comparable with those available for normal code development • Less efficient execution
- 11. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Bringing the workflow approach to the Multiagent world Agent-based workflows The basic idea is to use the expressiveness of the workflow metaphor to improve the agent communication process.
- 12. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows What is WADE? • is a software platforma based on JADE • A WADE application is also a JADE application • All JADE features are available in WADE too • Allows the execution of tasks using the workflow metaphor • Adopted the XPDL meta-model to facilitate import/export from/to a standard workflow representation format a For more information: http://jade.tilab.com/wade/
- 13. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Main components Figure: Source: [Telecom Italia, 2011b] WADE and WOLF In principle WADE supports “notepad-programming”, but it comes with a graphical development environment called WOLF [Telecom Italia, 2011b].
- 14. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Architecture Figure: Source: [Telecom Italia, 2011b]
- 15. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows A classroom case study using WADE • Now, it’s time to develop a simple but complete application using WADE ... • ... from scratch !
- 16. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Formal Definition • In mathematics, the factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal n • For example: 5! = 5 x 4 x 3 x 2 x 1 = 120 • According to the rule, the value of 0! is 1
- 17. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Implementing the application using the workflow metaphor Note We know ... The factorial problem could easily be implemented in one line, as the example above in LISP: (defun fa (n) (cond ((eq n 1) n) ((> n 1) (* (fa (- n 1) ) n ) ) ) By the other hand, this problem allows to explore the workflow metaphor, keeping us focused on the approach and not on out-of-scope issues.
- 18. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Implementing the application using the workflow metaphor • We will start by implementing a simple solution using only one workflow agent • Next, we will improve the application, enabling the parallel execution of sub-workflows
- 19. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows A workflow with only one actor
- 20. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Creating the Project • (1) Creating a Java Project
- 21. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Creating the Project • Creating a Java Project • (2) Adding WADE Nature
- 22. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Creating the Project • Creating a Java Project • Adding WADE Nature • (3) Configuring WADE
- 23. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE distribution structure Figure: Source: [Caire, 2008]
- 24. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Application Structure
- 25. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (4) Defining the Agent • The Factorial Agent will not inherit from the jade.core.Agent class directly • We will use the WorkflowEngineAgent a • All workflow agents are automatically registered in the DF a See FactorialAgent.java
- 26. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (5) Agent Types • WADE agents automatically registers with the DF providing a default description. • Such description contains the agent type as indicated in the cfg/types.xml file where relevant agent types are declared. Figure: See cfg/types.xml
- 27. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (6) Allowing the Agent to execute Workflows DispatchCapabilities Object By embedding a DispatchingCapabilities instance, an agent acquires the ability of launching workflows, setting and retrieving, workflow relevant data and listening to events generated by the execution of workflows [Telecom Italia, 2011a]. Figure: See FactorialAgent.java
- 28. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (7) Preparing the configuration for the first execution Configuration file Before lauching our application we still need to declare which agents we want to activate in it. This can be done by means of an "Application Configuration File". Figure: See cfg/configuration/Factorial.xml
- 29. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Running the application for the first time
- 30. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Basic workflow terminology • Workflow/Process
- 31. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Basic workflow terminology • Workflow/Process • Activity
- 32. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Basic workflow terminology • Workflow/Process • Activity • Transition
- 33. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 34. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 35. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 36. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 37. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 38. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 39. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows The WADE meta-model Figure: Source: [Telecom Italia, 2011b]
- 40. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 41. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 42. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 43. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 44. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 45. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 46. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 47. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 48. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 49. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 50. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows In practice Figure: Source: [Telecom Italia, 2011b]
- 51. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (8) Creating a Workflow • Workflows in WADE are Java classes that extend the WorkflowBehaviour class • Indirectly, this class extends our known JADE Behaviour • WOLF provides a view to edit a workflow in a bidirectional fashion. Figure: See FactorialWorkflow.java
- 52. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (9) (10) Executing Workflows Figure: See calculate method defined in FactorialAgent.java
- 53. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Running the application
- 54. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 55. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 56. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 57. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 58. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 59. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 60. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows WADE Delegation Model Figure: Source: [Telecom Italia, 2011b]
- 61. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows A workflow with two actors Executing sub-workflows Now, we will change the code to allow agents delegate the execution of sub-workflows to other agents
- 62. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Application Structure
- 63. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Changing Project Settings • (11) Creating the multiply agent (See MultiplyAgent.java)
- 64. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Changing Project Settings • Creating the mutiply agent (See MultiplyAgent.java) • (12) Adding multiplier to cfg/types.xml
- 65. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Changing Project Settings • Creating the mutiply agent (See MultiplyAgent.java) • Adding multiplier to cfg/types.xml • (13) Creating the multiplication sub-workflow (See MultiplyWorkflow.java)
- 66. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Changing Project Settings • Creating the mutiply agent (See MultiplyAgent.java) • Adding multiplier to cfg/types.xml • Creating the multiplication sub-workflow (See MultiplyWorkflow.java) • (14) Changing the project configuration (See cfg/configuration/Factorial.xml)
- 67. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (15) Changing the Factorial Agent Executing sub-workflows Now, we will change the code to allow the factorial agent keep on track of multiply agents life-cycle a. a See subscribe method defined in FactorialAgent.java
- 68. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows (16) Changing the Factorial Workflow Changing the workflow Now, we will change the workflow in order to execute the multiplication in parallel, joining the results at the end of all operations a. a See FactorialWorkflow.java
- 69. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Running the application
- 70. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Conclusion Questions? • A hands-on example on WADE • Much more examples and resources on http://jade.tilab.com/wade/ • See also the WADE tutorial at http://jade.tilab.com/wade/doc/tutorial/WADE- Tutorial.pdf Contact Information • Marcio Fuckner • marcio.fuckner@utc.fr
- 71. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Caire, G. (2008). WADE: an open source platform for workflows and agents. The Seventh International Conference On Autonomous Agents and Multiagent Systems. Telecom Italia (2011a). WADE Tutorial. Telecom Italia. Available at http://jade.tilab.com/wade/doc/tutorial/WADE-Tutorial.pdf. Telecom Italia (2011b). WADE User Guide. Telecom Italia. Available at http://jade.tilab.com/wade/doc/WADE-User-Guide.pdf. Workflow Management Coalition (2013).
- 72. UTC The workflow metaphor Agent-based workflows WADE Overview Architecture The Factorial case study General Information Implementation Preparing the Infrastructure Creating the Agent Creating the Workflow WADE Delegation Model Running sub-workflows Workflow Management Coalition Terminology and Glossary. Workflow Management Coalition. Available at http://www.wfmc.org.