System and method for stateful web-based computing

• US 20050198365A1
• Filed: 03/08/2005
• Published: 09/08/2005
• Est. Priority Date: 11/19/2003
• Status: Active Grant

• Current Assignee: Nexaweb Inc.
• Original Assignee: Coach K. Wei
• Inventors: Wei, Coach K.
• Granted Patent: US 7,761,878 B2
• Time in Patent Office: Days
• US Class Current: 709/237
• CPC Class Codes: G06F 16/84 Mapping; Conversion
• CPC Class Codes: G06F 40/143 Markup, e.g. Standard Generalized Markup Language [SGML] or Document Type Definition [DTD]
• CPC Class Codes: G06F 40/154 Tree transformation for tree-structured or markup documents, e.g. XSLT, XSL-FO or stylesheets
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/142 Managing session states for stateless protocols; Signalling session states; State transitions; Keeping-state mechanisms

Abstract

A method for providing “guaranteed message delivery” for network based communications between a client machine and a server. The client machine includes a Client Runtime Environment (CRE) and the server includes a Server Runtime Environment (SRE). The method includes the following steps. A first message queue is maintained in the CRE. A first unique identification is attached to the first message from the first message queue and the first message is sent from the CRE to the SRE via a network communication. The SRE receives the first message and sends an acknowledgement of the receipt of the first message to the CRE. Upon receiving of the acknowledgement within a certain time threshold, the CRE removes the first message from the first message queue in the CRE. A method of providing “server-push” of messages from the server to the client machine utilizing a push Servlet and a push API.

Claims

1. A method for providing “

guaranteed message delivery”

for network based communications between a client machine and a server, wherein said client machine comprises a Client Runtime Environment (CRE) and said server comprises a Server Runtime Environment (SRE), said method comprising;

maintaining a first message queue in said CRE;

attaching a first unique identification to a first message from said first message queue and sending said first message from said CRE to said SRE via said http communication;

receiving said first message by said SRE and sending an acknowledgement of said receipt of said first message by said SRE to said CRE; and

upon receiving of said acknowledgement by said CRE within a certain time threshold, removing said first message from said first message queue in said CRE.

2. The method of claim 1 wherein upon not receiving of said acknowledgement by said CRE within a certain time threshold, sending said first message again from said CRE to said SRE.

3. The method of claim 1 wherein upon not receiving of said acknowledgement by said CRE within a certain time threshold, raising an error condition in said CRE.

4. The method of claim 1 further comprising:

maintaining a second message queue in said SRE;

attaching a second unique identification to a second message from said second message queue and sending said second message from said SRE to said CRE;

receiving said second message by said CRE and sending an acknowledgement of said receipt of said second message by said CRE to said SRE; and

upon receiving of said acknowledgement by said SRE within a certain time threshold, removing said second message from said second message queue in said SRE.

5. A method for providing “

once-and-only-once message delivery”

for network-based communications between a client machine and a server, wherein said client machine comprises a Client Runtime Environment (CRE) and said server comprises a Server Runtime Environment (SRE), said method comprising;

maintaining a first message queue in said CRE;

attaching a first unique identification to a first message from said first message queue and sending said first message from said CRE to said SRE via said http communication;

receiving said first message by said SRE and checking whether said first message with said first unique identification has been previously received by said SRE or not; and

upon determining that said first message with said first unique identification has been previously received by said SRE, discarding said first message.

6. The method of claim 5 further comprising upon determining that said first message with said first unique identification has not been previously received by said SRE, maintaining said first message in said SRE.

7. The method of claim 6 further comprising:

maintaining a second message queue in said SRE;

attaching a second unique identification to a second message from said second message queue and sending said second message from said SRE to said CRE;

receiving said second message by said CRE and checking whether said second message with said second unique identification has been previously received by said CRE or not; and

upon determining that said second message with said second unique identification has been previously received by said CRE, discarding said second message.

8. The method of claim 7 further comprising upon determining that said second message with said second unique identification has not been previously received by said CRE, maintaining said second message in said CRE.

9. A method for providing “

guaranteed order message delivery”

for network based communications between a client machine and a server, wherein said client machine comprises a Client Runtime Environment (CRE) and said server comprises a Server Runtime Environment (SRE), said method comprising;

maintaining a first message queue in said CRE wherein said first message queue comprises at least a first message and a second message and said first message is ordered after said second message in said first message queue;

attaching a first unique identification to said first message wherein said first unique identification comprises a first indication that said first message is ordered after said second message;

sending said first message from said CRE to said SRE via said http communication;

receiving said first message by said SRE and checking whether said second message has been previously received by said SRE; and

upon determining that said second message has not been received yet, sending a request to said CRE for sending said second message.

10. The method of claim 9 further comprising upon determining that said second message has been already received by said SRE placing said first message and said second message in a SRE message storage so that said first message is ordered after said second message.

11. The method of claim 10 further comprising:

maintaining a second message queue in said SRE wherein said second message queue comprises at least a third message and a fourth message and said third message is ordered after said fourth message in said second message queue;

attaching a second unique identification to said third message wherein said second unique identification comprises a second indication that said third message is ordered after said fourth message;

sending said third message from said SRE to said CRE via said http communication;

receiving said third message by said CRE and checking whether said fourth message has been previously received by said CRE; and

upon determining that said fourth message has not been received yet, sending a request to said SRE for sending said fourth message.

12. The method of claim 11 further comprising upon determining that said fourth message has been already received by said CRE placing said third message and said fourth message in a CRE message storage so that said third message is ordered after said fourth message.

13. A method for performing ‘

server-push”

of information from a server to a client machine for a Java Servlet based web application via a request/response communication cycle comprising;

providing an application server having a Java Servlet Engine for running said Java Servlet based web application;

providing a push Servlet and a push Application Program Interface (API) wherein said push Servlet maintains open a network connection from said server to said client machine; and

wherein said Java Servlet based web application calls said push API to push information from said server to said client machine.

14. The method of claim 13 wherein said push API contains methods selected from a group consisting of sending “

push messages”

, checking “

push connection”

status, ending “

push connection”

, starting “

push connection” and

exiting ‘

wait’

mode of said push Servlet.

15. The method of claim 13 wherein said server receives a request from said client machine for receiving one or more “

push messages” and

said Java Servlet Engine creates a ServletRequest object and a ServletResponse object, enters said request into said ServletRequest and calls said push Servlet to process said request within a first thread.

16. The method of claim 15 wherein said push Servlet gains control of said first thread execution, holds onto said Servlet Request and said Servlet Response objects and waits for said one or more “

push messages”

without returning control back to said Java Servlet Engine.

17. The method of claim 16 wherein said Java Servlet based web application calls said push API to send said one or more “

push messages”

in separate threads.

18. The method of claim 17 wherein said push API upon receiving said send said one or more “

push messages”

, wakes up said push Servlet from a “

wait”

mode and said push Servlet writes said one or more “

push messages”

to said ServletResponse object and flushes them to said client machine and then waits for further “

push messages”

.

19. The method of claim 13 wherein said push Servlet maintain open said network connection from said server to said client machine by sending a response having a header instructing said client machine not to close said network connection until a certain condition.

20. The method of claim 19 wherein said header comprises a “

Content-type”

header field indicating that said response is a “

multipart”

mime-type response and said certain condition comprises an end of said “

multipart”

mime-type response

21. The method of claim 19 wherein said header comprises a “

Transfer-encoding”

header field indicating that said response is “

chunked” and

said certain condition comprises an end of said “

chunked”

response.

22. The method of claim 19 wherein said header comprises a “

Content-length”

header field indicating that said response'"'"'s content length is a number that is bigger than a sum of all content lengths of said push messages, and said certain condition comprises a total number of bytes to be delivered equals or exceeds said number.

23. The method of claim 18 wherein said Java Servlet based web application calls said push API to “

end push messages”

upon occurrence of a certain external event and wherein said API upon receiving said “

end push messages”

notifies said push Servlet and said push Servlet writes “

end push messages”

to said ServletResponse object, flushes it out to the client machine and returns control of said first thread execution back to said Java Servlet Engine.

24. The method of claim 23 wherein said Java Servlet Engine finishes said request/response cycle.

25. A system for performing ‘

server-push”

of information from a server to a client machine for a Java Servlet based web application via a request/response communication cycle comprising;

an application server having a Java Servlet Engine for running said Java Servlet based web application;

a push Servlet and a push Application Program Interface (API), wherein said push Servlet maintains open persistent connections from said server to said client machine; and

wherein said Java Servlet based web application calls said push API to push information from said server to said client machine.

26. The system of claim 25 wherein said push API contains methods selected from a group consisting of sending “

push messages”

, checking “

push connection”

status, ending “

push connection”

, starting “

push connection” and

exiting ‘

wait’

mode of said push Servlet.

27. The system of claim 25 wherein said server receives a request from said client machine for receiving one or more “

push messages” and

said Java Servlet Engine creates a ServletRequest object and a ServletResponse object, enters said request into said ServletRequest and calls said push Servlet to process said request within a first thread.

28. The system of claim 27 wherein said push Servlet gains control of said first thread execution, holds onto said Servlet Request and said Servlet Response objects and waits for said one or more “

push messages”

without returning control back to said Java Servlet Engine.

29. The system of claim 28 wherein said Java Servlet based web application calls said push API to send said one or more “

push messages”

in separate threads.

30. The system of claim 29 wherein said push API upon receiving said send said one or more “

push messages”

, wakes up said push Servlet from a “

wait”

mode and said push Servlet writes said one or more “

push messages”

to said ServletResponse object and flushes them to said client machine and then waits for further “

push messages”

.

31. The system of claim 25 wherein said push Servlet maintains open said network connection from said server to said client machine by sending a response having a header instructing said client machine not to close said network connection until a certain condition is met.

32. The system of claim 31 wherein said header comprises a “

Content-type”

header field indicating that said response is a “

multipart”

mime-type response and said certain condition comprises an end of said “

multipart”

mime-type response

33. The system of claim 31 wherein said header comprises a “

Transfer-encoding”

header field indicating that said response is “

chunked” and

said certain condition comprises an end of said “

chunked”

response.

34. The system of claim 31 wherein said header comprises a “

Content-length”

header field indicating that said response'"'"'s content length is a number that is bigger than a sum of all content lengths of said push messages, and said certain condition comprises a total number of bytes to be delivered equals or exceeds said number.

35. The system of claim 30 wherein said Java Servlet based web application calls said push API to “

end push messages”

upon occurrence of a certain external event and wherein said API upon receiving said “

end push messages”

notifies said push Servlet and said push Servlet writes “

end push messages”

to said ServletResponse object, flushes it out to the client machine and returns control of said first thread execution back to said Java Servlet Engine.

36. The system of claim 25 wherein said Java Servlet Engine finishes said request/response cycle.