JP4231241B2 - Network communication - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to communication between a client and a server computer (hereinafter also simply referred to as a server) .
[0002]
[Prior art]
Conventionally, when a client communicates with a Web server via a network, the client issues a next request after receiving a response corresponding to the already issued request. However, for the purpose of browsing a simple HTML document, the next request may be transmitted without waiting for a response from the server. For this purpose, there is no inconvenience to the user even if a request for acquiring the next document is issued without waiting for a response.
[0003]
[Problems to be solved by the invention]
However, in recent years, Web servers can provide clients with various services such as electronic commerce and mail distribution services. When receiving such a service, the client must strictly associate the transmitted request with the response from the server to the request. This is to prevent unexpected damage to the user. Therefore, the client cannot send the next request until there is a response from the server.
[0004]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique in which association with a response is appropriately performed even when requests are continuously transmitted.
[0005]
[Means for solving the problems and their functions and effects]
In order to solve the above-described problems, the present invention is configured as follows. That is,
A client that is connected via a network , acquires a print job from a server computer in which the print job is stored, using an HTTP protocol, and performs printing using a printer connected to the client;
To generate a request for print I follow the format of the HTTP protocol, at least the request generating unit response from the server computer to impart a first identifier for identifying the request for unfinished the body of the request When,
A request transmitter for transmitting the request to the server computer ;
A response receiving unit that receives from the server computer a response in which a second identifier is attached to a body part of a response that conforms to the format of the HTTP protocol;
An identifier determination unit that determines whether or not the response corresponds to the request based on the first identifier and the second identifier;
The gist is to provide.
[0006]
According to the client of the present invention, the correspondence between the request and the response can be collated based on the first identifier assigned to the request and the second identifier assigned to the response. For this reason, even if requests are continuously transmitted, it is possible to easily associate them with responses.
[0007]
The request generation unit may add an identifier that overlaps with an identifier assigned to a request for which a corresponding response has already been returned to a newly generated request. This is because if a response has already been returned, there is no need to distinguish between a request corresponding to the response and a newly generated request.
[0008]
The identifier determination unit may determine that the first identifier and the second identifier correspond to each other when the first identifier and the second identifier are the same. This is because the determination is facilitated. In addition, for example, it may be determined that the first identifier and the second identifier have a reciprocal relationship or the case where the sum of the two is 1 or 0.
[0009]
In addition, if the request generation unit generates the first identifier based on information unique to the client and information related to the generation order of the request data, the request generation unit may be an identifier generated by another client. A unique identifier without duplication can be given to the request. Information unique to the client can be, for example, a MAC address, an IP address, a manufacturing number, or the like assigned to the client. The information related to the generation order may be, for example, the date / time when the identifier is generated, the serial number of the generated identifier, or the like.
[0010]
The present invention is particularly effective when the predetermined protocol is HTTP (Hypertext Transport Protocol). This is because HTTP can easily cross a firewall, and for example, even when the client of the present invention is installed in a secure company, it is possible to easily access a server existing on the Internet.
[0011]
The present invention can be configured as such a client, and can also be configured as the following server computer. That is,
A server computer that transfers an accumulated print job using a HTTP protocol in response to a request from a client connected via a network,
A request with an identifier assigned to the body part of the request according to the format of the HTTP protocol, the request receiving unit receiving a request regarding printing from the client;
A response according to the request, including a response identifier corresponding to the identifier in a response body portion according to the format of the HTTP protocol, and generating a response,
A response transmitter for transmitting the response to the client;
Is a server computer.
[0012]
According to the server of the present invention, when a response corresponding to a request is generated, a reply identifier corresponding to the identifier given to the request is given to the response. Therefore, a client that receives such a response can appropriately associate the issued request with the received response. Note that it is preferable that the response generation unit assigns the same identifier as that assigned to the request to the response as a reply identifier. This is because the process can be simplified because it is not necessary to newly generate an identifier.
[0013]
The present invention can be configured in various modes in addition to the above-described modes as a client and a server. For example, a communication method in which a client communicates with a server on the network using a predetermined protocol, a communication method in which a server communicates with a client on the network using a predetermined protocol, and the client exists on the network A computer program for communicating with a server using a predetermined protocol, a computer program for a server to communicate with a client existing on a network using a predetermined protocol, a recording medium storing such a computer program, etc. It is an aspect.
[0014]
Here, the recording medium may be a computer readable medium such as a flexible disk, a CD-ROM, a DVD, a magneto-optical disk, an IC card, a ROM cartridge, a computer internal storage device (memory such as RAM or ROM), and an external storage device. Can be used.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in the following order based on examples.
A. Printing system:
B. Agent:
C. Print mediation server:
D. Communication processing:
E. effect:
F. Variations:
[0016]
A. Printing system:
FIG. 1 is an explanatory diagram showing a schematic configuration of a printing system according to the present embodiment. The printing system 10 is a system for the purpose of printing content browsed on the go mainly using the portable information terminal 12 with a printer PT at home or company. The content server 11, the portable information terminal 12, the print mediation server 13, and the client PC 14 constituting the printing system 10 are connected to each other via the Internet INT.
[0017]
Hereinafter, a rough flow of a printing procedure using this system will be described. First, the user displays desired content held by the content server 11 using a portable information terminal 12 such as a notebook computer, PDA, or mobile phone. The content server 11 is a server that provides users with various services such as a mail distribution service and a map distribution service. In this embodiment, it is assumed that the content server 11 provides a map distribution service. Accordingly, the map image MI distributed from the content server is displayed on the portable information terminal 12 in the figure.
[0018]
On the map image MI displayed on the portable information terminal 12, a print button PB is arranged. The user can transfer the print job to the print mediation server 13 by pressing this button. The print button PB is a hyperlink to the print mediation server 13, and when the user presses this button, the URL (Uniform Resource Locator) of the content server that is the link source of the map image MI is transferred to the print mediation server 13. It is a mechanism to be done. Although the URL is transferred here, the image data of the map image MI itself may be transferred.
[0019]
The user returns home from whereabouts and uses a program called an agent installed in the client PC 14 to print the print job on a home or company computer (client PC 14). The agent is software that performs a series of printing processes such as logon to the print mediation server 13, request / download of a print job, and printing to a printer. By using the agent, the user can easily print the content browsed on the go with a home or company printer.
[0020]
The agent and the print mediation server 13 perform communication using HTTP as a protocol. HTTP has the feature that it can easily cross firewalls. Accordingly, even an in-house computer connected to the Internet via a firewall can easily communicate with the print mediation server 13 using an agent.
[0021]
B. Agent:
FIG. 2 is a functional block diagram of the agent. The agent 15 includes a plurality of programs that are modularized as illustrated. Hereinafter, each module will be described with reference to FIGS. The communication control module 20 has a function as an interface that mediates communication with the print mediation server 13 in accordance with a virtual message issued by another module. A “virtual message” is a group of messages prepared to make each module appear as if it is directly sending / receiving a message to / from the print mediation server 13. By using this virtual message, each module can access the print mediation server 13 without being aware of the presence of the communication control module 20.
[0022]
FIG. 3 is a table showing an example of a virtual message. “RegPrinter” is a virtual message issued by the printer setting module 21 of the agent 15, and is a message used when registering a user's printer in the print mediation server 13. The user inputs parameters such as the printer model name, available paper, and whether or not the printer is compatible with color. Then, the printer setting module 21 issues a “RegPrinter” message with these parameters as arguments, and registers the printer used by the user in the print mediation server 13. If the registration is successful in the print mediation server 13, a printer ID is returned as a return value. If the registered number exceeds the specified number or the printer does not support it, “NG” is returned as a return value.
[0023]
“DelPrinter” is also a message issued by the printer setting module 21. This is a message used when deleting a printer registered in the print mediation server 13 by “RegPrinter”. The printer to be deleted is designated by the printer ID. If the print mediation server 13 has successfully deleted, “OK” is returned as a return value. If the designated printer does not exist, “NG” is returned.
[0024]
“GetJob” is a message issued by the printer management module 22 and used when acquiring a print job from the print mediation server 13. When receiving this message from the agent 15, the print mediation server 13 transfers the print job to the agent 15. As will be described later, since the print mediation server 13 has a function of converting all print jobs into PDF files, the substance of the PDF file is returned as a return value. If a job that is not stored in the print mediation server 13 is specified, a message “File Not Found” is returned as a return value. The agent 15 causes the print processing module 24 to print the PDF file acquired by “GetJob”.
[0025]
“PrinterStatus” is also a message issued by the printer management module 22. The printer management module 22 monitors the operating status of the printer, and notifies the print mediation server 13 of the status of the printer such as “ready (printable)” or “busy (unprintable)”, for example.
[0026]
“JobStatus” is also a message issued by the printer management module 22 and used when notifying the print mediation server 13 whether or not the print job acquired by “GetJob” has been printed normally.
[0027]
“GetModule” is a message issued by the version management module 23 and used when acquiring a new version of the module from the print mediation server 13.
[0028]
The agent management module 25 is a module that centrally manages the printer management module 22 and the version management module 23 described above.
[0029]
The agent browser 26 displays the home page of the print mediation server 13. The user performs user registration by registering a login name, password, and the like on this home page.
[0030]
Next, a detailed configuration of the communication control module 20 described above will be described. When the communication control module 20 receives a virtual message from each module, the communication control module 20 stores it in the virtual message queue 27. At a predetermined timing, the request generation unit 28 converts the virtual message into an HTTP request. The predetermined timing is, for example, a time set by the user or a timing when connected to the Internet at the time of dial-up. At the time of conversion, a unique message ID is generated based on the conversion time and the MAC address assigned to the computer on which the agent 15 is installed. The generated message ID is recorded in the body part of the HTTP request.
[0031]
The message ID generated in this way is, for example, as follows.
"Aabbccddeeff200204416110114"
Of these, “aabbccddeeff” represents the MAC address, “20020416” represents the date, and “110114” represents the time.
[0032]
FIG. 4A shows an example of the HTTP request generated in this way. In this figure, the message ID is simplified and indicated as “ABC”. The HTTP request includes a header part and a body part, and various commands defined in the HTTP standard are described in the header part. On the other hand, a virtual message and a message ID are recorded in the body part. In the case of the figure, it indicates that “PrinterStatus” is recorded as a virtual message. In the figure, “ready” is an argument for this virtual message and indicates that the printer is in a printable state.
[0033]
The communication control module 20 transmits an HTTP request to the print mediation server 13 by the request transmission unit 29. At this time, the history of the issued HTTP request is recorded in the request history holding unit 30. The recorded parameter includes at least a message ID and a virtual message.
[0034]
The response receiving unit 31 receives an HTTP response returned from the print mediation server 13. FIG. 4B shows an example of the HTTP response. The HTTP response is also composed of a header part and a body part, and as shown in the figure, a message ID, a virtual message, and a return value for the virtual message are recorded in the body part. In the case of the figure, the fact that the return value for “PrinterStatus” is “OK” is recorded. That is, it indicates that the print mediation server 13 has normally grasped the operating state of the printer.
[0035]
The ID determination unit 32 collates this HTTP response with the HTTP request recorded in the request history holding unit. The collation is performed by determining whether or not the message IDs given to both are the same. If there is an HTTP request having the same message ID as a result of the collation, the return value recorded in the HTTP response is transferred to the module that issued the virtual message that is the conversion source of the HTTP request. The return value is transferred by the return value transfer unit 33.
[0036]
C. Print mediation server:
FIG. 5 is a functional block diagram of the print mediation server 13. The print mediation server 13 is configured by installing software for realizing each functional unit shown in a general-purpose computer.
[0037]
The communication control unit 40 manages communication with other servers and clients. The communication control unit 40 includes a request reception unit 41 that receives an HTTP request, and a response transmission unit 42 that transmits an HTTP response.
[0038]
The UI providing unit 43 provides an HTML user interface in accordance with a request from the portable information terminal 12, the client PC 14, or the like. For example, it is used when there is a homepage browsing request from the agent browser 26.
[0039]
The user management unit 44 manages user login IDs, passwords, printers to be used, and the like. When there is a printer registration / cancellation request from the agent 15, the setting is changed.
[0040]
The job storage unit 45 stores a print job transferred from the portable information terminal 12. When there is a print job transfer request from the agent 15, the PDF conversion unit 46 is used to convert the print job into a PDF file. If the stored print job is simply a URL, an HTML document or image is acquired from the content server 11 at the URL destination and converted to a PDF file.
[0041]
The main control unit 47 performs various processes according to the HTTP request received by the communication control unit 40. When a message ID and a virtual message are stored in the HTTP request, processing such as printer registration, cancellation, and job transfer is performed using the above-described functional units in accordance with the virtual message. After the process is completed, an HTTP response in which a return value corresponding to the process is recorded is generated. When generating an HTTP response, the same message ID as the message ID recorded in the HTTP request to be processed is assigned (see FIG. 4B). The generated HTTP response is returned by the communication control unit 40 to the transmission source of the HTTP request.
[0042]
Note that the print mediation server 13 may be constructed as a so-called distributed system in which a part of the functional units described above is substituted for another server. For example, another independent server may perform PDF conversion, or another server may be responsible for user management.
[0043]
D. Communication processing:
FIG. 6 is a flowchart of communication processing between the agent 15 and the print mediation server 13. First, when receiving a virtual message from each module (step S10), the agent 15 stores the virtual message in the virtual message queue (step S11). Then, the virtual messages are sequentially read at a predetermined timing to generate an HTTP request (step S12). At this time, a message ID is given to the HTTP request. The agent 15 transmits the HTTP request generated in this way to the print mediation server 13 and records the history of the HTTP request transmitted to the request history holding unit 30 (step S13).
[0044]
When the print mediation server 13 receives the HTTP request transmitted in this manner (step S20), the print mediation server 13 performs various processes according to the virtual message recorded in the HTTP request (step S21). And the HTTP response which recorded the return value which is the processing result is produced | generated (step S22). At this time, the same message ID as the message ID assigned to the HTTP request to be processed is recorded in the HTTP response. The generated HTTP response is transmitted to the agent 15 (step S23).
[0045]
When the agent 15 receives the HTTP response (step S14), the agent 15 refers to the message ID recorded in the received HTTP response and searches the request history holding unit 30 for an HTTP request to which the same message ID is assigned (step S14). S15). Then, as a result of the search, the return value recorded in the HTTP response is transferred to the module that issued the virtual message that is the generation source of the corresponding HTTP request (step S16). Through such processing, each module of the agent 15 can appropriately acquire the return value corresponding to the issued virtual message from the print mediation server 13.
[0046]
E. effect:
FIG. 7 is an explanatory diagram illustrating an example of communication between the agent 15 and the print mediation server 13. In the figure, message IDs are indicated as ID1, ID2,. In the figure, an arrow from left to right represents an HTTP request, and an arrow from right to left represents an HTTP response. A downward arrow indicates the passage of time. According to the agent 15 and the print mediation server 13 described in this embodiment, the agent 15 can transmit HTTP requests one after another without waiting for an HTTP response to an already issued HTTP request. Since a common unique message ID (ID1 to ID5) is assigned to the HTTP request and the HTTP response corresponding to the HTTP request, the order of the HTTP responses returned from the print mediation server 13 is HTTP as illustrated. Even if the request is transmitted in a different order, the correspondence between the HTTP request and the HTTP response can be appropriately verified.
[0047]
F. Variations:
In the embodiment, the agent generates the message ID based on the MAC address and time. Therefore, the message IDs to be generated are all unique without overlapping. However, the agent 15 only needs to be able to distinguish between a request for which no response is returned and a newly generated request. Therefore, a message ID that overlaps the message ID assigned to the request for which a response has already been returned may be assigned to a newly generated request.
[0048]
FIG. 8 is an explanatory diagram showing an example of communication when duplicate message IDs are used. As shown in the figure, the agent 15 receives a response with ID1 and ID2 from the print mediation server 13 after transmitting a request with ID1 to ID4. Therefore, the agent can discriminate from other requests even if the message ID of ID1 or ID2 is reused and added to the request. In the case of the figure, the case where ID1 is reused is shown. As described above, if message IDs are used redundantly, for example, it is particularly effective for a system or the like that can use only a limited number of message IDs.
[0049]
As mentioned above, although the various Example of this invention was described, it cannot be overemphasized that this invention is not limited to these Examples, and can take a various structure in the range which does not deviate from the meaning. For example, the functions realized by software in the embodiments may be realized by hardware. Further, it may be used for communication between a server and a client in a system other than the printing system 10. In the embodiment, the communication control module generates the message ID in a unified manner, but each module may generate the message ID. In addition, although the message ID is recorded in the body part of the HTTP request / response, it may be recorded in the header part.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating a schematic configuration of a printing system.
FIG. 2 is a functional block diagram of an agent.
FIG. 3 is a table showing an example of a virtual message.
FIG. 4 is an explanatory diagram illustrating an example of an HTTP request and an HTTP response.
FIG. 5 is a functional block diagram of a print mediation server.
FIG. 6 is a flowchart of communication processing between an agent and a print mediation server.
FIG. 7 is an explanatory diagram illustrating an example of communication between an agent and a print mediation server.
FIG. 8 is an explanatory diagram illustrating an example of communication when a message ID is reused.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Printing system 11 ... Content server 12 ... Portable information terminal 13 ... Print mediation server 14 ... Client PC
DESCRIPTION OF SYMBOLS 15 ... Agent 20 ... Communication control module 21 ... Printer setting module 22 ... Printer management module 23 ... Version management module 24 ... Print processing module 25 ... Agent management module 26 ... Agent browser 27 ... Virtual message queue 28 ... Request generation part 29 ... Request Transmission unit 30 ... Request history holding unit 31 ... Response reception unit 32 ... ID determination unit 33 ... Return value transfer unit 40 ... Communication control unit 41 ... Request reception unit 42 ... Response transmission unit 43 ... UI providing unit 44 ... User management unit 45 ... Job storage unit 46 ... PDF conversion unit 47 ... Main control unit

Claims (9)

A client that is connected via a network , acquires a print job from a server computer in which the print job is stored, using an HTTP protocol, and performs printing using a printer connected to the client;
To generate a request for print I follow the format of the HTTP protocol, at least the request generating unit response from the server computer to impart a first identifier for identifying the request for unfinished the body of the request When,
A request transmitter for transmitting the request to the server computer ;
A response receiving unit that receives from the server computer a response in which a second identifier is attached to a body part of a response that conforms to the format of the HTTP protocol;
An identifier determination unit that determines whether or not the response corresponds to the request based on the first identifier and the second identifier;
With client. The client of claim 1,
The identifier determining unit determines that the first identifier and the second identifier correspond to each other when the first identifier and the second identifier are the same. The client of claim 1,
The request generation unit is a client that generates the first identifier based on information unique to the client and information related to a generation order of the requests. A server computer that transfers an accumulated print job using a HTTP protocol in response to a request from a client connected via a network,
A request with an identifier assigned to the body part of the request according to the format of the HTTP protocol, the request receiving unit receiving a request regarding printing from the client;
A response according to the request, including a response identifier corresponding to the identifier in a response body portion according to the format of the HTTP protocol, and generating a response,
A response transmitter for transmitting the response to the client;
A server computer comprising: A communication method for acquiring a print job using a HTTP protocol from a server computer connected via a network and storing the print job, and for a client performing printing using a printer connected to the server computer to communicate with the server computer Because
(A) to generate a request for print I follow the format of the HTTP protocol, a response from at least the server computer to impart a first identifier for identifying the request for unfinished the body of the request Process,
(B) transmitting the request to the server computer;
(C) receiving from the server computer a response in which a second identifier is assigned to a body part of the response according to the format of the HTTP protocol;
(D) determining whether the response corresponds to the request based on the first identifier and the second identifier;
Including a communication method. A communication method in which a server computer that transfers an accumulated print job using a HTTP protocol in response to a request from a client connected via a network communicates with the client .
(A) a request in which an identifier is given to a body part of a request according to the format of the HTTP protocol, and a request regarding printing is received from the client;
(B) a response corresponding to the request, including a reply identifier corresponding to the identifier in a body part of the response according to the format of the HTTP protocol, and generating the response;
(C) sending the response to the client;
Including a communication method. A client connected via a network , obtains a print job using a HTTP protocol from a server computer in which the print job is stored, and a client that performs printing using a printer connected to the server computer communicates with the server computer A computer program,
To generate a request for print I follow the format of the HTTP protocol, a function of imparting a first identifier for a response from at least the server computer to identify a request for unfinished body portion of the request,
A function of transmitting the request to the server computer;
A function of receiving from the server computer a response in which a second identifier is assigned to the body part of the response according to the HTTP protocol format;
A function for determining whether or not the response corresponds to the request based on the first identifier and the second identifier;
A computer program for realizing a computer. A computer program for communicating with a client by a server computer that transfers an accumulated print job using a HTTP protocol in response to a request from a client connected via a network,
A function in which an identifier is given to a body part of a request according to the format of the HTTP protocol, and a request for printing is received from the client;
A response corresponding to the request, including a reply identifier corresponding to the identifier in a response body part according to the format of the HTTP protocol, and generating the response;
A function of transmitting the response to the client;
A computer program for realizing a computer. Recording medium the computer program and computer readable recording according to claim 7 or 8.

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