Framework for modeling continuations in workflows

• US 20070239499A1
• Filed: 03/30/2006
• Published: 10/11/2007
• Est. Priority Date: 03/30/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Shukla, Dharma, Mehta, Mayank, Raman, Karthik, Talbert, Nathan, Schmidt, Robert, Sagar, Akash
• Granted Patent: US 8,069,439 B2
• Time in Patent Office: Days
• US Class Current: 705/7
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06Q 10/06 Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
• CPC Class Codes: G06Q 10/06316 Sequencing of tasks or work
• CPC Class Codes: G06Q 10/0633 Workflow analysis

Abstract

Enabling creation of control flow patterns in a workflow via continuations. Each continuation represents an activity execution context for an activity executing in the workflow by a workflow engine virtualizing a managed execution environment. Responsive to a request, the activity execution context is recreated via the continuation and the activity is executed within the recreated context.

Claims

1. A method for enabling creation of control flow patterns in a workflow, said method comprising:

generating a plurality of continuations for one or more program fragments during execution of the program fragments by a meta-runtime engine, said meta-runtime engine virtualizing a managed execution environment having fixed functionality, each of the generated plurality of continuations representing an activity execution context;

storing the generated plurality of continuations to create an execution journal for the program fragments;

selecting one of the stored continuations from the execution journal and retrieving the selected continuation responsive to a request from a user;

recreating the activity execution context associated with the retrieved continuation; and

executing, within the re-created activity execution context, the program fragments associated with the retrieved continuation.

2. The method of claim 1, wherein generating the plurality of continuations comprises capturing a runtime state associated with the meta-runtime engine and capturing an application state associated with the program fragments.

3. The method of claim 1, further comprising:

enabling the user to browse the execution journal; and

receiving, from the user, a selection of the one of the stored continuations from the execution journal.

4. The method of claim 1, further comprising enabling a user to browse the execution journal via an application programming interface exposed by an activity writer.

5. The method of claim 1, wherein storing the generated plurality of continuations comprises storing the generated plurality of continuations according to an execution order of activities associated with the program fragments.

6. The method of claim 1, further comprising enabling the user to search the execution journal for continuations that are being executed.

7. The method of claim 1, further comprising enabling the user to search the execution journal for continuations that are not being executed.

8. The method of claim 1, further comprising enabling the user to sort the execution journal.

9. The method of claim 1, further comprising persisting the selected continuation through passivation.

10. The method of claim 1, further comprising defining a data boundary for the continuations.

11. The method of claim 10, wherein defining the data boundary comprises determining the extent, binding, and scoping of variables.

12. The method of claim 1, wherein generating the plurality of continuations comprises generating the plurality of continuations responsive to a request from an activity associated with one or more of the program fragments.

13. The method of claim 1, wherein one or more computer-readable media have computer-executable instructions for performing the method of claim 1.

14. A system for modeling continuations in workflows, said system comprising:

a memory area for storing an execution journal representing a plurality of continuations associated with program fragments executed by an execution machine, each of the plurality of continuations representing an activity execution context; and

a processor configured to execute computer-executable instructions for;

generating the plurality of continuations for the program fragments during execution of the program fragments;

storing the generated plurality of continuations in the memory area;

providing an interface to the execution journal in the memory area;

responsive to a request for a particular continuation received via the provided interface, retrieving the particular continuation from the execution journal in the memory area;

recreating the activity execution context associated with the retrieved continuation; and

executing, within the re-created activity execution context, the program fragments associated with the retrieved continuation.

15. The system of claim 14, wherein each of the plurality of continuations represents an execution state of one of the program fragments.

16. The system of claim 14, wherein the user comprises one or more of the following:

a human, an application program, and an operating system.

17. The system of claim 14, further comprising means for managing the generated plurality of continuations.

18. One or more computer-readable media having computer-executable components, said components comprising:

an execution machine component for executing a plurality of program fragments associated with a workflow, said execution machine component virtualizing a managed execution environment having fixed functionality;

a state component for generating a plurality of continuations for the program fragments being executed by the execution machine component, each of said plurality of continuations including a runtime state and an application state, said runtime state indicating a scheduler queue status, said application state indicating an activity status; and

a memory component for serializing the continuations; and

a replay component for re-creating, responsive to a request from a user, the runtime state and the application state associated with one or more of the continuations serialized by the memory component and for executing, within the re-created runtime state and the application state, the program fragments associated with the one or more continuations.

19. The computer-readable media of claim 18, wherein each of the generated plurality of continuations represents an activity execution context.

20. The computer-readable media of claim 18, wherein the continuations serialized by the memory component model one or more of the following:

a control flow pattern, an iteration, a parallel for each statement, a state machine, a page flow controller, a sequence generator, and a continuation.