PROCESSING MODEL-BASED COMMANDS FOR DISTRIBUTED APPLICATIONS

• US 20090112873A1
• Filed: 10/26/2007
• Published: 04/30/2009
• Est. Priority Date: 10/26/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Kulkarni, Amol Sudhakar, Sahi, Sundeep, Panditharadhya, Prasad Sripathi, Wu, Haoran Andy, Sedukhin, Igor, Christensen, Erik B., Nanjangud Bhaskar, Karthik Arun
• Granted Patent: US 7,974,939 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 8/10 Requirements analysis; Specification techniques

Abstract

The present invention extends to methods, systems, and computer program products for processing model based commands for distributed applications. Embodiments facilitate execution of model-based commands, including software lifecycle commands, using model-based workflow instances. Data related to command execution is stored in a shared repository such that command processors can understand their status in relationship to workflow instances. Further, since the repository is shared, command execution can be distributed and balanced across a plurality of different executive services. Embodiments also include model-based error handling and error recovery mechanisms.

Claims

1. At a computer system, the computer system including an executive service and a repository that stores models, a method for processing a model-based command for a distributed application, the method comprising:

an act of receiving a command request for a distributed application, the command request including a command reference to a command definition model defining a corresponding command, the command request also including a reference to model, the command request indicating that the corresponding command is to be implemented for the application model;

an act of creating a command record for the received command request in the repository, the command record for storing information related to implementing the command request;

an act of identifying a workflow model from the command definition model, the workflow model describing how to implement the received command request;

an act of accessing the workflow model from the repository;

an act of creating an instance of the workflow from the workflow model, the workflow instance having a command ID and including a set of pre-defined activities configured to interoperate to implement the command request;

an act of storing a the command ID in the command record;

an act of submitting the application reference to the workflow instance to initiate the workflow instance; and

an act of recording information related to the behavior of the workflow instance within the command record as the workflow instance implements the command request for the application model.

2. The method as recited as recited in claim 1, wherein the act of receiving a command request comprises an act of receiving a software lifecycle command request.

3. The method as recited as recited in claim 1, wherein the act of receiving a software lifecycle command request comprises receiving a software lifecycle command request selected from among:

verify, clean, check, fix, deploy, start, stop, undeploy.

4. The method as recited in claim 1, wherein the act of creating a command record for the received command request in the repository comprises an act of creating a command record from a corresponding command record model.

5. The method as recited in claim 1, wherein the act of creating an instance of the workflow comprises an act creating a workflow that includes one or more driver-related activities and one or more state-related activities.

6. The method as recited in claim 1, wherein the act of creating an instance of the workflow comprises an act creating a workflow that includes one or more activities pre-defined for use with the command request.

7. The method as recited in claim 1, further comprising:

an act of the workflow instance interoperating with a work breakdown module to prepare the application model for consumption by driver services.

8. The method as recited in claim 1, further comprising:

an act of locking the application model while the workflow instance implements the command request for the application model.

9. The method as recited in claim 1, further comprising:

an act of receiving a request for the status of the workflow instance from a user tool, the status request include the command ID for the workflow instance;

an act of using the command ID to referring to the command record for the workflow instance;

an act of accessing the state of the workflow instance from the command record; and

an act of returning the status to the user tool.

10. The method as recited in claim 1, further comprising:

an act of detecting that the workflow instance has completed; and

an act of updating the command record to indicate the workflow instance completed such that completion of the workflow can be reflected in response to subsequent queries.

11. The method as recited in claim 1, further comprising:

an act of extending the processing of model based commands by adding or modifying a command or workflow model.

12. The method as recited in claim 1, further comprising;

an act of recording error information related to execution of the command in the repository; and

an act of user tools subsequently accessing the error information to reason about problems with the application model; and

an act of the user tools acting upon the problems to correct the problems.

14. The method as recited in claim 12, wherein the act of receiving a command request for a distributed application comprises an act of receiving a software lifecycle command for a distributed application.

15. The method as recited in claim 12, wherein the act of determining that the workflow instance is to be stopped comprises an act of determining that the workflow instance has completed.

16. The method as recited in claim 12, wherein the act of determining that the workflow instance is to be stopped comprises:

an act of receiving a subsequent cancel call requesting that the workflow instance be stopped prior to the workflow instance completing implementation of the command request for the model application;

an act of issuing a stop request to the workflow instance;

17. The method as recited in claim 16, wherein the act of receiving a subsequent request to stop the workflow instance comprises:

an act of determining that the cancel call is not responding; and

an act of receiving a terminate call requesting that the workflow be terminated in response to the determination that he cancel call is not responding.

13. At a computer system, the computer system including an executive service and a repository that stores models, a method for releasing a command definition model for further use, the method comprising:

an act of receiving a command request for a distributed application, the command request including a command reference to a command definition model defining a corresponding command, the command request also including a reference to model, the command request indicating that the corresponding command is to be implemented for the application model;

an act of creating an instance of the workflow from a corresponding workflow model, the workflow instance including a set of pre-defined activities configured to interoperate to implement the command request;

an act of locking the application model to prevent further access to the application model while the workflow instance implements the command request for the model application.

an act of submitting the application model reference to the workflow instance to initiate the workflow instance;

an act of recording information related to the behavior of the workflow instance within the command record as the workflow instance implements the command request for the application model;

an act of determining that the workflow instance is to be stopped;

an act of determining that the workflow instance is stopped; and

an act of releasing the lock on the application model such that other commands can be implemented for the application model.

18. At a computer system, the computer system including a plurality of executive services and a repository that stores models, a method for distributing the implementation of a command, the method comprising:

an act of a first executive service receiving a command request for a distributed application, the command request including a command reference to a command definition model defining a corresponding command, the command request also including a reference to model, the command request indicating that the corresponding command is to be implemented for the application model;

an act of the first executive service determining that it is already running a plurality of other model-based commands;

an act of the first executive service querying the repository to determine if other executive services are available;

an act of the first executive service receiving an indication that a second executive service is available for processing model-based commands; and

an act of the first executive service passing the command request to the second executive service in response to the indication that the second executive service is available so as to balance the load of command processing across the plurality of executive services.

19. The method as recited in claim 18, wherein the act of a first executive service receiving a command request for a distributed application comprises an act of receiving a software lifecycle command request.

20. The method as recited in claim 18, further comprising:

an act of a third executive service receiving a request for the status of the workflow instance from a user tool, the status request include the command ID for the workflow instance;

an act of the third executive service using the command ID to referring to a command record for the workflow instance in the repository;

an act of the third executive service accessing the state of the workflow instance from the command record; and

an act of the third executive service returning the status to the user tool.