Method, apparatus, and program for distributing a document object model in a web server cluster

• US 20030131051A1
• Filed: 01/10/2002
• Published: 07/10/2003
• Est. Priority Date: 01/10/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Lection, David B., Masselle, Eric L.
• Granted Patent: US 7,181,489 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: G06Q 10/10 Office automation; Time management

Abstract

An asynchronous, peer-to-peer design is provided for synchronizing data on machines within a cluster using messaging. The data may be represented in memory as a document object model in secondary storage. Messaging may be handled by a messaging system with topic destinations. The design supports persistence management, locking, and transactions with rollback, and maintains a uniform state for the data across all nodes and secondary storage at all times. Furthermore, barring catastrophic failure of all machines in the cluster and secondary storage, there is no possibility of losing committed data.

Claims

1. A method for processing shared data comprising:

receiving a request to perform a task on shared data;

creating a work item message for the task; and

publishing the work item message to a messaging service.

2. The method of claim 1, wherein the task is one of an edit task and a locking task.

3. The method of claim 2, wherein the step of publishing the work item message comprises posting the work item message to an edit topic.

4. The method of claim 1, wherein the task is one of an edit task and an unlocking task.

5. The method of claim 4, wherein the step of publishing the work item message comprises posting the work item message to a transaction topic.

6. A method for processing shared data comprising:

receiving a work item message from a messaging service;

processing the work item message; and

publishing a result to the messaging service.

7. The method of claim 6, wherein the step of receiving a work item message comprises consuming a work item message from an edit topic.

8. The method of claim 7, further comprising placing the work item message in an edit queue.

9. The method of claim 8, wherein the step of processing the work item message comprises:

determining whether the work item message was created by a current server cluster node; and

performing a request task corresponding to the work item message if the work item message was created by the current server cluster node.

10. The method of claim 9, wherein the step of processing the work item message further comprises:

waiting until the work item message is removed from the edit queue if the work item message was not created by the current server cluster node.

11. The method of claim 7, wherein the work item message comprises a locking request.

12. The method of claim 11, wherein the step of processing the work item message comprises locking a portion of the shared data.

13. The method of claim 6, wherein the step of receiving a work item message comprises consuming a work item message from a transaction topic.

14. The method of claim 13, wherein the step of processing the work item message comprises:

performing a request task corresponding to the work item message on a clone of at least a portion of the shared data.

15. The method of claim 13, wherein the work item message comprises an unlocking request.

16. The method of claim 15, wherein the step of processing the work item message comprises unlocking at least a portion of the shared data.

17. The method of claim 16, wherein the result comprises a modified portion of the shared data.

18. A method for processing shared data comprising:

receiving a result from a messaging service;

processing the result; and

updating the shared data based on the result.

19. The method of claim 18, wherein the step of processing the result comprises modifying the shared data in persistent storage.

20. The method of claim 18, wherein the step of processing the result comprises updating the shared data in memory.

21. An apparatus for processing shared data comprising:

receipt means for receiving a request to perform a task on shared data;

creation means for creating a work item message for the task; and

publication means for publishing the work item message to a messaging service.

22. The apparatus of claim 21, wherein the task is one of an edit task and a locking task.

23. The apparatus of claim 22, wherein the publication means comprises means for posting the work item message to an edit topic.

24. The apparatus of claim 21, wherein the task is one of an edit task and an unlocking task.

25. The apparatus of claim 24, wherein the publication means comprises means for posting the work item message to a transaction topic.

26. An apparatus for processing shared data comprising:

receipt means for receiving a work item message from a messaging service;

processing means for processing the work item message; and

publication means for publishing a result to the messaging service.

27. The apparatus of claim 26, wherein the receipt means comprises means for consuming a work item message from an edit topic.

28. The apparatus of claim 27, further comprising means for placing the work item message in an edit queue.

29. The apparatus of claim 28, wherein the processing means comprises:

means for determining whether the work item message was created by a current server cluster node; and

means for performing a request task corresponding to the work item message if the work item message was created by the current server cluster node.

30. The apparatus of claim 29, wherein the processing means further comprises:

means for waiting until the work item message is removed from the edit queue if the work item message was not created by the current server cluster node.

31. The apparatus of claim 27, wherein the work item message comprises a locking request.

32. The apparatus of claim 31, wherein the processing means comprises means for locking a portion of the shared data.

33. The apparatus of claim 26, wherein the receipt means comprises means for consuming a work item message from a transaction topic.

34. The apparatus of claim 33, wherein the processing means comprises:

means for performing a request task corresponding to the work item message on a clone of at least a portion of the shared data.

35. The apparatus of claim 33, wherein the work item message comprises an unlocking request.

36. The apparatus of claim 35, wherein the processing means comprises means for unlocking at least a portion of the shared data.

37. The apparatus of claim 36, wherein the result comprises a modified portion of the shared data.

38. An apparatus for processing shared data comprising:

receipt means for receiving a result from a messaging service;

processing means for processing the result; and

update means for updating the shared data based on the result.

39. The apparatus of claim 38, wherein the processing means comprises means for modifying the shared data in persistent storage.

40. The apparatus of claim 38, wherein the processing means comprises means for updating the shared data in memory.

41. A computer program product, in a computer readable medium, for processing shared data comprising:

instructions for receiving a request to perform a task on shared data;

instructions for creating a work item message for the task; and

instructions for publishing the work item message to a messaging service.

42. A computer program product, in a computer readable medium, for processing shared data comprising:

instructions for receiving a work item message from a messaging service;

instructions for processing the work item message; and

instructions for publishing a result to the messaging service.

43. A computer program product, in a computer readable medium, for processing shared data comprising:

instructions for receiving a result from a messaging service;

instructions for processing the result; and

instructions for updating the shared data based on the result.