JP2008176483A - Information providing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce network traffic by reducing the frequency of HTTP requests. <P>SOLUTION: An update checking script 331a performed in a script execution environment 33 of an information providing server 30 checks whether a log file 341 is updated by, for example, checking the update time and date of the log file 341, and when updated, chat application 131 executed in the script execution environment 13 of a client terminal 10 is notified of the updating. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an information providing system that reduces network traffic.

  In recent years, a script executed on the HTTP client side performs asynchronous communication with a server that provides a service, and a so-called web application that utilizes a technology that dynamically reflects the result in the HTTP client area without screen transition is a service application. It has come to be used for provision.

  In such a web application, on the HTTP client side, for example, necessary information is acquired and executed by xmlHttpRequest in JavaScript (registered trademark).

  However, in general, the HTTP protocol is a so-called Pull type protocol that provides information by a response to a request (request) from a client, and therefore, without request from the HTTP client, the HTTP server to the HTTP client. Push type communication that transmits information cannot be performed.

  For this reason, when the web application side wants to respond quickly to a file change or the like on the HTTP server side, for example, the web application side transmits an HTTP request at a predetermined short interval to obtain a response of the HTTP server. There was a need.

  However, in such a method, it is necessary to frequently transmit HTTP requests, and it is necessary to execute processing according to a response from the HTTP server. Further, since the HTTP request has a lot of additional information such as header information, it is not desirable to transmit more than necessary from the viewpoint of the load on the network. The applicant does not know the existence of known technical documents related to the background art.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an information providing system capable of reducing network traffic by reducing the frequency of HTTP requests.

  In order to solve this problem, an information providing system according to the present invention includes an information providing unit that provides information using an HTTP server, an update confirming unit that repeatedly confirms whether or not information to be monitored is updated, and one session. , An information providing server comprising a notification means for notifying that the information has been updated according to the detection output of the update detection means, an information acquisition means for obtaining information provided by the information provision means, and a notification from the notification means And an information using terminal including an HTTP client having an acquisition instruction unit that instructs the information acquisition unit to acquire information.

  The information provided by the information providing server includes, for example, output information such as a chat service, a file sharing service, a search service, and a DB access service. “In one session” means that one session is maintained between the notification unit and the acquisition instruction unit of the HTTP client, and a plurality of notifications can be transmitted in the session. The “repetitive confirmation” by the update confirmation means includes, for example, confirmation every predetermined time, irregular confirmation by a timer that can be changed according to the operation state, and the like.

  In addition, the HTTP server has a difference detection unit that detects a difference of the update detection unit when the update detection unit detects an update of information to be monitored, and the difference detection unit detects while the notification unit of the HTTP server notifies It is good also as a structure which notifies including the difference information which shows the difference which carried out, and the information acquisition means of an HTTP client acquires the difference information in notification. Further, the HTTP server includes time measuring means for obtaining an elapsed time since the notification means transmits the notification, and dummy information transmission means for causing the notification means to transmit dummy information when the elapsed time exceeds a predetermined threshold. It is good also as a structure.

  In addition, the information providing server device according to the present invention includes an information providing unit that provides information to the terminal device, an update confirmation unit that repeatedly confirms whether or not information to be monitored is updated, and an update detection unit in one session. And a notification means for notifying the terminal device that the information has been updated according to the detected output.

  The information utilization terminal device according to the present invention includes an information providing means for providing information by an HTTP server, an update confirmation means for repeatedly confirming whether or not information to be monitored is updated, and an update detection means in one session. An information use terminal that uses information provided by an information providing server provided with a notification means for notifying that information has been updated in accordance with the detection output of the information acquisition means for acquiring information provided by the information providing means And an acquisition instruction means for instructing the information acquisition means to acquire information in response to a notification from the notification means.

  According to the present invention, the update confirmation unit of the information providing server apparatus repeatedly confirms whether or not the information to be monitored is updated, and the notification unit performs the information update according to the detection output of the update detection unit in one session. By notifying that there has been an update, there is no need to send an HTTP request at regular intervals from the information-use terminal device side to check the information update, and the notification from the notification means can be monitored in one session. Only when information is updated, information can be requested from the information providing means. Thereby, the frequency of the HTTP request from the information utilization terminal device side can be reduced, and the network traffic can be reduced.

  In addition, the HTTP server has a difference detection unit that detects a difference of the update detection unit when the update detection unit detects an update of information to be monitored, and the difference detection unit detects while the notification unit of the HTTP server notifies If the information acquisition unit of the HTTP client is configured to acquire the difference information being notified, the HTTP request is transmitted from the HTTP client side in response to the notification and becomes a monitoring target. There is no need to acquire information, which can contribute to further traffic reduction.

  Further, the HTTP server includes time measuring means for obtaining an elapsed time since the notification means transmits the notification, and dummy information transmission means for causing the notification means to transmit dummy information when the elapsed time exceeds a predetermined threshold. With this configuration, it is possible to prevent the session between the notification unit and the HTTP client acquisition instruction unit from being disconnected due to a timeout.

  The present invention can be applied to an information providing system that provides services such as chat and file sharing to client terminals connected via a network, for example.

(overall structure)
As shown in FIG. 1, for example, the information providing system according to the first embodiment of the present invention includes a client terminal 10 used by a user who receives information, and an information providing server 30 connected to the client terminal 10 via a network 20. And. The information providing server 30 provides information providing services such as chat and file sharing. The client terminal 10 and the information providing server 30 are constituted by an information processing apparatus such as a personal computer having a CPU (Central Processing Unit), a memory, etc., for example, and as shown in FIG. 1 by executing a control program. Function.

  The client terminal 10 includes a communication control unit 11 that controls communication via the network 20, an HTTP client 12 that uses an HTTP service, and a display unit 14 having a display screen. The HTTP client 12 includes a script execution environment 13 that can execute JavaScript (registered trademark), and the script execution environment 13 executes processing on the client side used for using the information providing service provided by the information providing server 30. By executing the script in the script execution environment 13, a web application using the HTTP client 12 such as the chat application 131 and the file sharing application 132 can be executed. In this embodiment, the Internet Explorer 6.0 is used as the HTTP client 12, and the same applies thereafter.

  The information providing server 30 includes a communication control unit 31 that controls communication via the network 20, an HTTP server 32 that provides an HTTP service, a script execution environment 33 that executes processing described in a script language, and a hard disk device ( HDD) 34. The script execution environment 33 executes processing described in languages such as Perl and JSP (Java (registered trademark) ServerProgram), for example, a chat service for chatting between users, and a file for sharing files between users Processing such as a shared service, a file search service for searching for a target file, an information providing service that provides an HTTP server 32 as a front end, such as a DB access service that provides access to a database, is executed. In this embodiment, Perl 5.8 is used as the script language execution environment 33, and so on.

  In this information providing system, the chat service is provided via a log file 341 that can be commonly accessed (read, added, etc.) by members who perform chat. A user who wants to use the chat service logs in to the HTTP server 32 by operating the client terminal 10. Specifically, for example, the HTTP client 12 specifies a URL (for example, “http: //srv_url/chat.html”) corresponding to the chat service, requests login to the HTTP server 32, and sends a request from the HTTP server 32. Authentication information such as a user ID and a password is transmitted in response to the response. The login process is performed by, for example, the chat service 331 executed in the script execution environment 33. When the login is permitted, the HTTP server 32 transmits display data constituting the chat screen to the HTTP client 12. In response to this, the HTTP client 12 displays a chat window 142 in a browser window 141 in the display unit 14, for example, as shown in FIG. Further, the chat service 331 creates a chat state storage file 343 for each chat group, for example, and manages the chat state (login state of each member, etc.) of the chat group.

  In the chat window 142, there are provided an input field for inputting characters to be transmitted, an area for displaying information about the user of the other party who is chatting, a log display area 142a for displaying a chat log, and the like. In FIG. 2, for convenience, the log display area 142a is illustrated with a description of the corresponding definition in the display data. In practice, however, the log display area 142a has, for example, as shown in FIG. , The string in the log is displayed. Also, in FIG. 2, a frame that is defined by an iframe tag in display data (chat.html) described later and that receives a notification (upper frame update command) from an update confirmation script 331a (catupdate.cgi) described later. For convenience, it is illustrated as a reference numeral 142b. However, since the frame is defined as a non-display state, it is not actually displayed on the screen.

  FIG. 4 is a diagram illustrating an example of a log file 341 in which messages from users in a group performing chat are recorded. A message input via the HTTP client 12 operated by a user who uses the chat service is supplied to the HTTP server 32 via the communication control unit 11, the network 20, and the communication control unit 31, together with information indicating the user. Recorded in the log file 341.

  FIG. 5 is a diagram illustrating an example of display data 131 a supplied from the HTTP server 32 to the HTTP client 12 and displaying the chat window 142. However, the technique of the present invention includes a part for determining the display style in the chat window 142, an input field for inputting characters to be transmitted, an area for displaying information about the user of the other party who is chatting, and a means for acquiring these. Parts that are not directly related to are omitted or simplified for convenience. This also applies to the following. The function (updatefunc (v)) defined in the Script tag issues xmlHttpRequest to the HTTP server 32, acquires character data indicating the chat contents from the log file 341, and within the div tag in the display data 131a. This function outputs to the area of. The HTTP client 12 displays chat contents in the chat window 142 in accordance with the display data 131a. Although not shown in FIG. 5, the chat application 131 defines a chat termination process in accordance with, for example, a button instruction or a menu selection. An end notification is transmitted to the HTTP server 32 side, and the chat window 142 is closed.

  FIG. 6 shows an example of the update confirmation script 331a in which processing for monitoring the update of the log file 341 is defined. In this example, processing is defined by the Perl language. When the HTTP client 12 sends a request to the URL of the update confirmation script 331a, the processing of the update confirmation script 331a is started, and the script execution environment 33 follows the definitions of the second and third lines in FIG. The predetermined header information transmitted to the client is output to the buffer. Subsequently, the script execution environment 33 transmits the header information and the like to the HTTP client 12 in response to the command $ | = 1 on the eighth line. Note that this instruction ($ | = 1) causes the flash to transmit the data held in the buffer (contents held in the buffer of the HTTP server 32 by the print statement of the line executed so far) in the Perl language. It is an instruction. In this embodiment, a print statement for outputting dummy data (character string “0123...”) For reliably executing the flush instruction on the eighth line is added. Thereafter, the value of the flag $ fin in the script execution environment 33 indicates the end condition (for example, the content of the chat state storage file 343 (continue.txt) is changed by the chat end notification from the HTTP client 12). Until the value [condition that becomes a logic false such as 0] is satisfied, the processing in the while instruction is executed and the update of the log file 341 is monitored at regular intervals (in the while loop, the function (subprocedure ) & Getchatlines are substituted into the variable $ af and compared with the initial value $ bf to determine whether or not there is an update).

  When the log file 341 is updated by writing or the like by a user participating in the chat, the number of lines in the log file 341 increases. Update monitoring can be performed, for example, by acquiring the number of lines in the log file 341 using the function & getchatchlines and comparing it with the number of lines ($ bf) at the previous confirmation. As a result, if the log file 341 has been updated, the script execution environment 33 executes the flush instruction after executing the print statement in the if statement, and does not execute the print statement or the like if not updated.

  The “print” statement in the “if” statement outputs a command (instruction [parent.updatefunc] for instructing an update of a frame higher than the frame that requested the update confirmation script 331a) specified in the “if” statement to the buffer. 33 causes the HTTP client 12 to transmit the contents of the buffer in response to the subsequent flush statement ($ | = 1). That is, each time the log file 341 is updated, the update confirmation script 331a transmits an instruction to the HTTP client 12 to instruct an update of the upper frame (“index.html” that requested the “chatupdate.cgi”). The display data 133a is instructed to be updated.

(Chat service operation)
FIG. 7 is a sequence diagram illustrating a log update process in the chat service.
When the user instructs to use the chat service, the HTTP client 12 requests the display data 131a (chat.html) of the chat window 142 from the HTTP server 32 (S101). In response to this, the HTTP server 32 supplies the display data 131a shown in FIG. 5 to the HTTP client 12 (S102). When the display data 131a is supplied, the HTTP client 12 requests the update confirmation script 331a (chatdate.cgi) according to the request of the update confirmation script 331a defined in the iframe tag in the display data 131a as described above. (S105).

  When the update confirmation script 331a is requested, the script execution environment 33 starts executing the update confirmation script 331a. The update confirmation script 331a first transmits header information and the like (S106), and thereafter monitors the update of the log file 341 every predetermined time (every execution of the above-mentioned while loop in FIG. 6) (S201, S202). ,..., S203). When the update of the log file 341 is detected (S202), the update confirmation script 331a notifies the HTTP client 12 to that effect (S107).

  As described above, the notification includes a script (parent.updatefunc) that instructs to update a frame higher than the frame that requested the output (that is, the frame based on the display data 131a). The HTTP client 12 executes the function updatefunc (v) described above. As a result, the log file 341 is requested again (S108), and the character corresponding to the log file 341 (S109) supplied in response thereto is displayed in the display data 131a (chat. html) in a div tag. As a result, the contents of the new chat are displayed in the log display area 142 a in the chat window 142.

  By repeating such an operation, an HTTP request for requesting a log file can be transmitted only when the log file 341 is updated, the display data 131a can be updated, and the contents of the chat can be displayed.

  Note that the chat service 331 manages the state of each chat group by the chat state storage file 343 (continue.txt), and when the chat ends, for example, when all users log out, the value of the chat state storage file 343 is set to 0. And The update confirmation script 331a shown in FIG. 6 monitors the chat state by the function & cont, and when the value of the chat state storage file 343 becomes 0, the variable $ fin to which the value of the function & cont is substituted is stored. The value becomes “0” indicating logic false, the processing of the above while loop is terminated, and the update confirmation script 331a finally outputs </ body> </ html> (S110) to terminate the session. . As described above, when the reception of the frame for receiving the notification from the update confirmation script 331a (the frame defined by the <iframe> tag in FIG. 5 described above) is completed, the HTTP client 12 displays the <body in the display data 131a. > The function donLoad () is executed according to the description in the tag (<body onLoad = “donLoad ()”>). Note that onLoad indicates a process that is executed when all displays defined in the <body> tag are completed. By executing this function doonLoad (), the characters “chat has ended” indicating that the chat has ended are displayed in the log display area 142a.

(effect)
In the conventional chat system using an HTTP client, an HTTP request is transmitted at a predetermined interval and a display reflecting the content of the chat is performed. Therefore, the frequency of the HTTP request increases and traffic increases. There was a problem. On the other hand, in this information providing system, as described above, the update confirmation script (chapdate.cgi) 331a executed on the information providing server 30 side monitors the update of the log file 341, and there is an update. Only, the log file can be requested from the HTTP server 32 and the display of the log can be updated. Thereby, the frequency of an HTTP request can be reduced and traffic can be reduced.

  In this information providing system, the update confirmation script 331a executed on the server side repeatedly confirms the update of the log file 341 at short intervals while the while loop is repeated, so the update of the log file 341 is confirmed. Therefore, if the chat service 331a confirms the update of the log file 341 at a sufficiently short interval, the log of the log in the chat application 131 for the update of the log file 341 can be transmitted. Responsiveness of display update can be improved.

  Further, in this information providing system, when the chat is ended, the information </ body> </ html> indicating the end of the frame defined by the <iframe> tag is transmitted from the server side. A process defined by onLoad in the <body> tag, for example, a display indicating the end of chat defined by the function donLoad () in FIG. 5 described above can be executed.

(Modification)
In the above embodiment, as shown in FIG. 5, the frame definition by the iframe tag is defined in the display data 131a in advance. However, after the first updatefunc function is executed, the iframe tag dynamically Processing may be defined so that a frame definition is added. As a result, after the chat application 131 is activated, the latest chat log is acquired, and then the chat update confirmation by the update confirmation script 331a can be started. That is, in more detail, it may take time for some reason to display the main chat screen (for example, corresponding to the above-mentioned “http: //srv_url/chat.html”). For this reason, when the definition of iframe is static, a plurality of requests are sent to the HTTP server 32 during the display of the main screen. On the other hand, if the iframe is dynamically generated, the log up to that point can be acquired at once by completing a display of the main screen once, and the number of communication with the HTTP server 32 can be reduced. It is possible to reduce the communication efficiency.

  In the above-described embodiment, the HTTP client 12 requests the update confirmation script 331a only once. However, when a communication error occurs, the request may be issued again.

(Information transmission on the server side without a certain interval)
In the above-described embodiment, the notification is transmitted when there is an update. However, the dummy information may be transmitted every predetermined period regardless of whether there is an update. In this case, on the HTTP server 32 side, instead of the processing shown in FIG. 6 described above, for example, as shown in FIG. 9, even if the log file 341 is not changed in the while loop, “” (single-byte space) or the like The dummy information is output to the buffer and transmitted to the HTTP client 12 side by the flush command.

  In the case where there is no chat update for a long time, in the process shown in FIG. 6 described above, transmission to the HTTP client 12 is not performed for a long time, and a timeout may occur on the HTTP client 12 side. However, in the process shown in FIG. 9, for example, as shown in FIG. 10, information is transmitted to the HTTP client 12 for each log confirmation process. Can be prevented (S405, S407), and the HTTP client 12 can be prevented from timing out.

  In the first embodiment described above, the update confirmation script 331a monitors the update of the log file 341 on the HTTP server 32 side, and only notifies that when there is an update. For example, FIG. 11 and FIG. 12, when there is an update, the difference in the log file 341 may be transmitted to the HTTP client 12 side.

  When the start of chat is instructed, the chat application 131 obtains the display data 131a shown in FIG. 11 described above, and requests an update confirmation script 331a according to the definition in the iframe tag. In response to this, the update confirmation script 331a starts the processing of FIG. 12, first executes the print statement from the second line to the eighth line, and executes the print statement so far with the flush statement on the ninth line. Send the contents of the buffer. In the print statement on the 8th line, a script instructing execution of the getLog () function is output. When a response including such a script is received, the chat application 131 displays the function getLog () in the display data 131 a. According to the definition, the previous log is acquired, and the line feed code is converted and inserted into the log display area 142a of the display data 131a.

  Thereafter, as shown in FIG. 13, the update confirmation script 331a monitors the update of the log file 341. When there is an update, the update confirmation script 331a obtains a difference between the log files before and after the update and obtains a predetermined variable ($ chatupdate). And is sent to the HTTP client 12 side as a response to the iframe in the display data 131a (S304).

  The chat application 131 is chatupdate. When there is a response from cgi, parent. In response to the updatefunc instruction, the parent. The updatefunc function is executed with the variable $ chatupdate in the updatefunc instruction as an argument (v). By executing the updatefunc function, the chat application 131 adds the character specified by the argument v to the log display area defined by the div tag in the display data 131a, and updates the display of the log display area 142a. As a result, the updated log contents are displayed in the log display area 142a. When the chat ends, the update confirmation script 331a outputs the end information (</ body> </ html>) (S305) and ends the session, as in the first embodiment. In response to this, the chat application 131 displays in the log display area 142a the character “chat has ended” indicating that the chat has ended.

  In the first embodiment described above, it is necessary to request the log file 341 from the chat application 131 side in response to the notification from the update confirmation script 331a. In the second embodiment, the chat application 131 side first requests the log file 341. By simply requesting the update confirmation script 331a, the difference between the log files 341 can be acquired sequentially. As a result, traffic can be further reduced.

  The technical idea of the present invention is not limited to the above-described embodiments. For example, in the above description, the chat service has been described as an example. However, when using services such as the file sharing service 332, the search service 333, and the DB access service 334, the HTTP server 32 side also uses the same service as the chat application 131. Data update etc. is monitored, and when there is an update etc., it is notified to the HTTP client 12 side, and the script execution environment 13 obtains the execution result of the service, so that the same effect as described above can be obtained. . In each of the above-described embodiments, an example in which the update of the log file 341 is confirmed every time the while loop of the update confirmation script 331a is executed has been described. However, in the script execution environment 33, the $ sleep instruction in the update confirmation script 331a Is added as a variable, and when the update frequency of the log file 341 is low, for example, a time to stop the processing with the $ sleep instruction is added. Variations such as making adjustments such as lengthening are also conceivable.

It is a block diagram which shows the structural example of the information provision system which concerns on Example 1 of this invention. It is a figure which shows the example of a display of the display part of the client terminal of the said information provision system. It is a figure which shows the example of the display content displayed on the said display part. It is a figure which shows the example of the log file hold | maintained at HDD of the information provision server of the said information provision system. It is a figure which shows the example of the display data provided to a chat application. It is a figure which shows the example of the server side script used for the process by the side of an HTTP server. It is a sequence diagram which shows the example of communication in provision of a chat service. It is a figure which shows the example of the display data which added the content of the log file. It is a figure which shows the example of the server side script in a modification. It is a sequence diagram which shows the example of communication in a modification. It is a figure which shows the structural example of the display data in the information provision system which concerns on Example 2 of this invention. It is a figure which shows the example of the server side script used for the process by the side of an HTTP server. It is a sequence diagram which shows the example of communication in provision of a chat service.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Client terminal, 12 ... HTTP client, 13 ... Script execution environment, 131 ... Chat application, 20 ... Network, 30 ... Information providing server, 33 ... Script execution environment, 331 ... Chat service, 331a ... Update check script, 341 ... logfile.

Claims (6)

An information providing means for providing information by an HTTP server, an update detecting means for repeatedly checking whether or not the information to be monitored is updated, and in one session, the update detecting means updates the information to be monitored. An information providing server comprising a notification means for notifying that the information has been updated when detected;
An information use terminal comprising an HTTP client, comprising: an information acquisition means for acquiring information provided by the information providing means; and an acquisition instruction means for instructing the information acquisition means to acquire information in response to a notification from the notification means; An information providing system characterized by comprising: The HTTP server has a difference detection unit that detects a difference of the update detection unit when the update detection unit detects an update of the information to be monitored.
The notification means of the HTTP server notifies including the difference information indicating the difference detected by the difference detection means during the notification,
The information providing system according to claim 1, wherein the information acquisition unit of the HTTP client acquires the difference information in the notification. The HTTP server is
Time measuring means for obtaining an elapsed time since the notification means transmits the notification;
3. The information providing system according to claim 1, further comprising: dummy information transmission unit that causes the notification unit to transmit dummy information when an elapsed time exceeds a predetermined threshold value. 4. Information providing means for providing information to the terminal device;
Update detection means for repeatedly checking whether or not the information to be monitored is updated;
An information providing server device comprising: a notification unit that notifies the terminal device that information has been updated according to a detection output of the update detection unit in one session. Information providing means for providing information by an HTTP server, update detecting means for repeatedly confirming whether or not the information to be monitored is updated, and updating of information in accordance with the detection output of the update detecting means in one session An information use terminal that uses information provided by an information providing server provided with a notification means for notifying that there has been,
An information acquisition unit that is executed on an HTTP client and acquires information provided by the information providing unit, and an acquisition instruction unit that instructs the information acquisition unit to acquire information in response to a notification from the notification unit An information utilization terminal device characterized by the above. Information providing means for providing information by an HTTP server, update detecting means for repeatedly confirming whether or not the information to be monitored is updated, and updating of information in accordance with the detection output of the update detecting means in one session An information use program that uses information provided by an information providing server provided with a notification means for notifying that there has been,
An information acquisition step that is executed on an HTTP client and acquires information provided by the information providing unit, and an acquisition instruction step that instructs the information acquisition step to acquire information in response to a notification from the notification unit An information utilization program characterized by

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