STREAMING CONTENT AND PLACEHOLDERS

• US 20140330874A1
• Filed: 05/01/2013
• Published: 11/06/2014
• Est. Priority Date: 05/01/2013
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Novak, Michael John, Guzak, Chris, Hoogerwerf, Scott David, Fields, David C., Ranjit, Sangeeta, Govrin, Amnon Itamar, Reiniger, Kiernon, Ramani, Ramanarayanan, Krishnamurhty, Raghu, Santhanam, Subha, Shekel, Oded Yehuda
• Granted Patent: US 9,405,767 B2
• Time in Patent Office: Days
• US Class Current: 707/827
• CPC Class Codes: G06F 16/16 File or folder operations, e.g. details of user interfaces specifically adapted to file systems
• CPC Class Codes: G06F 16/176 Support for shared access to files; File sharing support
• CPC Class Codes: G06F 16/182 Distributed file systems
• CPC Class Codes: G06F 16/252 between a Database Management System and a front-end application
• CPC Class Codes: H04L 65/61 for supporting one-way streaming services, e.g. Internet radio
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

Aspects of the subject matter described herein relate to file system placeholders. In aspects, placeholders may be used by a client to represent remote file system objects. The placeholders may include metadata and may also include none, some, or all of the content of the represented remote file system objects. In response to a request to access content of a file system object represented by a placeholder, a client may obtain needed data from a remote storage system and stream or not stream the data to the requesting application based on whether the requesting application is capable of streaming the data.

Claims

1. A method implemented at least in part by a computer, the method comprising:

receiving an indication of a file system object of a local file system of a client, the file system object represented by a placeholder, the placeholder being stored on the local file system, the client structured to obtain metadata of the file system object from the placeholder, the client structured to synchronize the local file system with a remote storage system, the metadata sufficient to allow the client, while offline with respect to the remote storage system, to obtain namespace information about the file system object from the placeholder, the placeholder including data that identifies the remote storage system from which data of the file system object is obtainable;

receiving a request to access content of the file system object;

determining, based on the placeholder, whether the content resides on the local file system;

if the content resides on the local file system, determining whether the content is up-to-date and, if so, providing the content from the local file system;

if the content does not reside on the local file system, determining whether an application to which the content is to be provided is structured to access the content via streaming or whether the application to which content is to be provided is not structured to access the content via streaming;

if the application to which the content is to be provided is structured to access the content via streaming, performing actions, comprising;

obtaining at least a portion of the file system object from the remote storage system,

updating the placeholder to indicate that the content is available from the local file system, and

providing the content to the application.

2. The method of claim 1, wherein determining, based on the placeholder, whether the content resides on the local file system comprises consulting a data structure of the placeholder, the data structure indicating what portions of the file system object reside on the local file system.

3. The method of claim 1, wherein determining whether the content is up-to-date comprises comparing a local version of the file system object with a remote version of the file system object, the local version stored in the placeholder, the remote version stored on the remote storage system.

4. The method of claim 1, wherein determining whether an application to which the content is to be provided is structured to access the content via streaming comprises accessing a data structure stored on the local file system, the data structure having been created in conjunction with installing the application, the data structure indicating whether the application is structured to access the content via streaming.

5. The method of claim 1, wherein determining whether an application to which the content is to be provided is structured to access the content via streaming comprises determining that the application is not structured to access the content via streaming if the application is a legacy application.

6. The method of claim 1, wherein determining whether an application to which the content is to be provided is structured to access the content via streaming comprises receiving a call from the application, the call directed to an interface that is compatible with streaming the content, the file system having at least two interfaces for accessing the content, one of the two interface being compatible with streaming the content, another of the two interfaces not being compatible with streaming the content.

7. The method of claim 1, wherein obtaining at least a portion of the file system object comprises obtaining the at least a portion based on a type associated with the file system object.

8. The method of claim 7, wherein obtaining the at least a portion based on a type associated with the file system object comprises obtaining all the content of the file system object before providing access to the content of the file if the type is an image type.

9. The method of claim 7, wherein obtaining the at least a portion based on a type associated with the file system object comprises obtaining all data of a compressed file that is within the file system object if the file system object is compressed and the request is to access any portion of the compressed file.

10. The method of claim 1, wherein obtaining at least a portion of the file system object comprises obtaining a calculated amount of playback data of the file system object, the calculated amount of playback data based on a bitrate of the file system object, the bitrate included in the placeholder.

11. In a computing environment, a system, comprising:

a store having computer storage elements that persist file system metadata for local file system objects of a local file system and that persist placeholders for remote file system objects of a remote storage system, the placeholders including metadata of the remote file system objects without requiring that the remote file system objects exist in the store;

a placeholder manager structured to create, populate, and maintain the placeholders to ensure that placeholders exists for remote file system objects in a namespace at least if the remote file system objects do not completely exist on the store; and

a streaming manager, hosted on a client, the streaming manager structured to perform actions, comprising;

receiving a request to access content of a file system object;

determining, based on a placeholder, whether the content resides on the local file system;

if the content resides on the local file system, determining whether the content is up-to-date and, if so, providing the content from the local file system;

if the content does not reside on the local file system, determining whether an application to which the content is to be provided is structured to access the content via streaming or whether the application to which content is to be provided is not structured to access the content via streaming;

if the application to which the content is to be provided is structured to access the content via streaming, performing actions, comprising;

obtaining at least a portion of the file system object from the remote storage system,

updating the placeholder to indicate that the content is available from the local file system, and

providing the content to the application.

12. The system of claim 11, further comprising a capabilities detector structured to determine whether an application to which the content is to be provided is structured to access the content via streaming.

13. The system of claim 12, wherein the capabilities detector being structured to determine whether an application to which the content is to be provided is structured to access the content via streaming comprises the capabilities detector being structured to access a data structure stored on the local file system, the data structure having been created in conjunction with installing the application, the data structure indicating whether the application is structured to access the content via streaming.

14. The system of claim 12, wherein the capabilities detector being structured to determine whether an application to which the content is to be provided is structured to access the content via streaming comprises the capabilities detector being structured to receive a call from the application, the call directed to an interface that is compatible with streaming the content, the file system having at least two interfaces for accessing the content, one of the two interface being compatible with streaming the content, another of the two interfaces not being compatible with streaming the content.

15. The system of claim 12, wherein the streaming manager is further structured to ensure that all of the content is available from the local file system prior to providing the content to the application if the application is not structured to access the content via streaming.

16. The system of claim 11, wherein the streaming manager is further structured to determine the at least a portion to obtain based on a type associated with the file system object.

17. The system of claim 16, wherein the streaming manager is further structured to determine that the at least a portion includes all the content of the file system object that is not currently on the store if the type is an image type.

18. The system of claim 16, wherein the streaming manager is further structured to determine that the at least a portion includes all data of a compressed file that is within the file system object if the file system object is compressed and the request is to access any portion of the compressed file.

19. A computer storage medium having computer-executable instructions, which when executed perform actions, comprising:

receiving a request for data of a file system object indicated by a client, the client having a client file system, the client file system having file system objects in which all content is located on the client file system and file system objects in which less than all content is located on the client file system, the client having placeholders that represent at least the file system objects in which less than all content is located on the client file system, the file system object being represented by a placeholder stored on the client file system, the placeholder identifying a remote storage system from which the data of the file system object is obtainable, the client structured to stream content of the file system object from the remote storage system to an application hosted on the client if the application is structured to access the content via streaming and to ensure that all content of the file system object is available on the client file system if the application is not structured to access the content via streaming; and

providing the data of the file system object from the remote storage system.

20. The computer storage medium of claim 19, wherein providing the data of the file system object comprises sending all of a compressed file that is within the file system object, the client further structured to request all of the compressed file if the file system object is compressed and the application requests access to any portion of the compressed file.