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BACKGROUND
This invention relates generally to a printer interface for use in a
network printing context and, more particularly, to a parsing system which
allows for efficient processing of queries transmitted from a client
station to a target printer by way of a network connection.
Electronic printing systems typically include an input section, sometimes
referred to as an input image terminal ("IIT"), a controller, sometimes
referred to as an electronic subsystem ("ESS") and an output section or
print engine, sometimes referred to as an image output terminal ("IOT").
In one type of electronic printing system, manufactured by Xerox.RTM.
Corporation, known as the DocuTech.RTM. electronic printing system, a job
can be inputted to the printing system from, among other sources, a
network or a scanner. An example of a printing system with both network
and scanner inputs is found in the following patent:
U.S. Pat. No. 5,170,340
Patentees: Prokop et al.
Issued: Dec. 8, 1992
When a scanner is employed to generate the job, image bearing documents are
scanned so that the images therein are converted to image data for use in
making prints. When a network is used to generate the job, a stream of
data, including various job related instructions and image data, expressed
in terms of a page description language is captured, decomposed and stored
for printing. As is known, a network job can have its origin in a remote
client, such as a workstation, or a print server with a storage device.
Jobs provided at the IIT may be stored in a memory section, sometimes
referred to as "electronic precollation memory". An example of electronic
precollation memory may be found in the following patent:
U.S. Pat. No. 5,047,955
Patentees: Shope et al.
Issued: Sep. 10, 1991
U.S. Pat. No. 5,047,955 discloses a system in which input image data of a
job is rasterized and compressed. The compressed, rasterized image data is
then stored, in collated form, in a job image buffer. Once the job has
been stored in the job image buffer, a selected number of job copies can
be decompressed and printed without further job rasterization.
In one area related to electronic printing, namely digital copying, a
demand for "multifunctionality" continues to grow. As illustrated by the
following patent, a multifunctional digital copier can assume the form of
an arrangement in which a single electrostatic processing printer is
coupled with a plurality of different image input devices, with such
devices being adapted to produce image related information for use by the
printer.
U.S. Pat. No. 3,957,071
Patentee: Jones
Issued: Jul. 27, 1971
U.S. Pat. No. 3,957,071 discloses that the image related information, in
one example, could have its origin in video facsimile signals, microfilm,
data processing information, light scanning platens for full size
documents, aperture cards and microfiche.
The following patents also relate to the area of multifunctional digital
copying:
U.S. Pat. No. 4,821,107
Patentees: Naito et al.
Issued: Apr. 11, 1989
U.S. Pat. No. 5,021,892
Patentees: Kita et al.
Issued: Jun. 4, 1991
U.S. Pat. No. 5,175,633
Patentees: Saito et al.
Issued: Dec. 29, 1992
U.S. Pat. No. 5,223,948
Patentees: Sakurai et al.
Issued: Jun. 29, 1993
U.S. Pat. No. 5,276,799
Patentee: Rivshin
Issued: Jan. 4, 1994
U.S. Pat. No. 5,307,458
Patentees: Freiburg et al.
Issued: Apr. 26, 1994
Multifunctional copying devices are typically adapted to store a plurality
of jobs for eventual printing. In one example, jobs are ordered for
printing in an arrangement referred to as a "print queue". Xerox Network
Systems have employed the concept of the print queue for at least a decade
to manage jobs at network printers. Further teaching regarding network
printing is provided in the following patent:
U.S. Pat. No. 5,436,730
Patentee: Hube
Issued: Jul. 25, 1995
The concept of a print queue is integral to operation of Xerox' DocuTech
Printing System as exemplified in the following patent:
U.S. Pat. No. 5,164,842
Patentees: Gauronski et al.
Issued: Nov. 17, 1992
A print queue particularly well suited for use with a multifunctional
printing system is disclosed by the following patent:
U.S. Pat. No. 4,947,345
Patentees: Paradise et al.
Issued: Aug. 7, 1990
It has been found that a typical digital copier is particularly well suited
for use with a network printing arrangement in which the digital copier is
interfaced with a client (e.g. workstation) by way of a suitable network
connection and a print server. The following patents represent examples of
servers suitable for use with printing systems:
U.S. Pat. No. 5,113,494
Patentees: Menendez et al.
Issued: May 12, 1992
U.S. Pat. No. 5,179,637
Patentee: Nardozzi
Issued: Jan. 12, 1993
U.S. Pat. No. 5,220,674
Patentees: Morgan et al.
Issued: Jun. 15, 1993
U.S. Pat. No. 5,113,494 discloses an arrangement in which a plurality of
nodes communicate with one another by way of a local area network
communication line. In one example, a hardcopy of a job could be processed
at a scan node while an electronic copy of the same job could be processed
at a print node.
U.S. Pat. No. 5,179,637 discloses a system for distributing print jobs
received from a print image data source among a set of print engines and
associated processors. One or more data files containing the information
required to print one or more copies of an image are submitted to a
scheduler and the scheduler interprets the job control information in the
data file(s) for the image and passes the data files(s) to an image
processor.
U.S. Pat. No. 5,220,674 discloses a local area print server which functions
in cooperation with a plurality of clients and a plurality of printers to
facilitate communication between the clients and the printers. The server
includes various subsystems, such as a status collection subsystem that
maintains a wide range of state information regarding virtually every
subsystem with which the server communicates. The status collection
subsystem includes a notification facility which sends reports of printing
system status changes or events to appropriate network components internal
and external to the local area print server that would have an interest in
knowing them.
Further detailed description of the network printing area is provided in
U.S. Pat. No. 5,551,686 to Sanchez et al.
The disclosure of each reference mentioned or discussed in the above
Background is incorporated herein by reference.
On the increasingly popular world-wide-web (www), hypertext markup language
(html) specifies the display of information on a "client" computer, and
hypertext transfer protocol (http) provides a neutral mechanism for the
transfer of information from a "server" computer to a "client" computer
over the TCP/IP network protocol. Of particular interest is the neutral
aspect, in which the transfer and display of information does not depend
on the client computers operating system or processor configuration, but
only on the capabilities of a protocol-compliant "browser". Such software
is widely available for most computers at this time. Information
transferred and displayed to the client includes both static information
defined in advance and dynamic information computed at the time that a
client makes a request to the server. Publicly available server software
often includes the common gateway interface (CGI) which allows the server
to invoke a software program which may be passed user specified
parameters, and whose output will be transferred to, and displayed on the
client computer.
Print and document processing machines can use html and http as interfaces
for control and status, and design of these machines benefits greatly from
use of such interfaces for several reasons. First, development costs are
lower and deployment schedules shorter since the mechanism can be used by
many clients without the necessity of writing the client display software
(often referred to as "user interface" or UI) for each operating system
and processor that clients use. Second, it is straightforward to define
multi-lingual interfaces by storing the information in multiple languages
on the server, permitting the server to be accessed in multiple languages
by different clients concurrently. Third, upgrades or changes can be made
to the print or document processing machine's capabilities without the
inconvenience of the vendor developing new client display software and of
the client having to install new software on every client computer for
each such upgrade.
In a network printing system, such as that disclosed by U.S. Pat. No.
5,220,674, a significant number of queries are passed between a given
client and one or more printing subsystems to determine selected
information regarding a given printing subsystem, such as machine settings
for or status of the given printing subsystem. It is believed to be known
that, in one example, the CGI can be employed to generate information in
response to a given query, provided a program is provided for both writing
out certain static data, such as certain basic information identifying the
printing subsystem being queried, and dynamic information, such as a
listing of jobs currently in a queue and the respective states of those
jobs.
Commonly, for each type of query to be submitted, a program to generate
both the static data and the dynamic data is developed. Creating a program
to accommodate for each type of query, however, can be both time consuming
and tedious. Moreover, providing a program for each query is inefficient
since much of the code for a number of queries overlaps. It would be
desirable to provide a system in which a single program is provided in
such a manner that the amount of code required to handle the set of
queries submitted to a given printing subsystem is minimized.
SUMMARY OF THE INVENTION
In accordance with the disclosed embodiment of the present invention, there
is provided a printing system disposed in a local or wide area network in
which one of a plurality of queries is transmitted from a client to a
server for obtaining a set of information including both a file with
static information and a subset of dynamic information. The subset of
dynamic information varies as a function of one or more print related
characteristics of a document processing system with which the server
communicates, and the printing system comprises: a) a parsing subsystem,
communicating with the client for receiving the one of the plurality of
queries, said parsing subsystem facilitating the obtaining of the set of
information by copying a portion of the file, in response to reading a
first instruction, and communicating the copied portion at the server for
storage thereat; b) a query resolving subsystem, communicating with said
parsing subsystem, for obtaining the subset of dynamic information from
the document processing system in response to said parsing system reading
a second instruction; and c) wherein the copied portion of the file and
the subset of dynamic information are combined for output thereof at the
client.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a networked digital copier suitable for
receiving a job developed in accordance with the present invention;
FIG. 2 is a block diagram depicting a multifunctional, network adaptive
printing machine;
FIG. 3 is a block diagram of a network controller for the printing machine
of FIG. 2;
FIG. 4 is a block diagram showing the network controller of FIG. 3 in
greater detail;
FIG. 5 is a schematic block diagram showing a query handling system
embodying the present invention;
FIG. 6A is a schematic block diagram illustrating an Internet based query
system in which a plurality of programs is provided to accommodate for the
various queries which are to be submitted to a given printing subsystem;
and
FIG. 6B is a schematic block diagram illustrating an Internet based query
system in which a single template ("Extended HTML") is provided, along
with a plurality of files, to implement a printing subsystem querying
system in which one program is employed to manage the various queries.
DESCRIPTION OF THE INVENTION
While the present invention will hereinafter be described in connection
with a preferred embodiment thereof, it will be understood that it is not
intended to limit the invention to that embodiment. On the contrary, it is
intended to cover all alternatives, modifications and equivalents as may
be included within the spirit and scope of the invention as defined by the
appended claims.
Referring to FIG. 1 of the drawings, a digital copier system of the type
suitable for use with the preferred embodiment is shown. As shown, the
system includes a document feeder 1 and an operation (and display) panel
2. After desired conditions have been entered on the operation panel 2,
the document feeder 1 conveys a document to a predetermined reading
position on an image reading device 3 and, after the document has been
read, drives it away from the reading position. The image reading device 3
illuminates the document brought to the reading position thereof. The
resulting reflection from the document is transformed to a corresponding
electric signal, or image signal, by a solid state imaging device, e.g., a
CCD (Charge Coupled Device) image sensor. An image forming device 4 forms
an image represented by the image signal on a plain paper or a
thermosensitive paper by an electrophotographic, thermosensitive, heat
transfer, ink jet or similar conventional system.
As a paper is fed from any one of paper cassettes 7 to the image on forming
device 4, the device 4 forms an image on one side of the paper. A duplex
copy unit 5 is constructed to turn over the paper carrying the image on
one side thereof and again feed it to the image forming device 4. As a
result, an image is formed on the other side of the paper to complete a
duplex copy. The duplex copy unit 5 has customarily been designed to
refeed the paper immediately or to sequentially refeed a plurality of
papers stacked one upon the other, from the bottom paper to the top paper.
The papers, or duplex copies, driven out of the image forming device 4 are
sequentially sorted by a output device 6 in order of page or page by page.
Applications, generally 8, share the document feeder 1, operation panel 2,
image reading device 3, image forming device 4, duplex unit 5, output
device 6, and paper cassettes 7 which are the resources built in the
copier system. As will appear, the applications include a copier
application, a printer (IOT) application, a facsimile (Fax) application
and other applications. Additionally, the digital copier system is coupled
with a network by way of a conventional network connection 9.
Referring to FIG. 2, a multifunctional, network adaptive printing system is
designated by the numeral 10. The printing system 10 includes a printing
machine 12 operatively coupled with a network service module 14. The
printing machine 12 includes an electronic subsystem 16, referred to as a
video control module (VCM), communicating with a scanner 18 and a printer
20. In one example, the VCM 16, which is described in detail in U.S. Pat.
No. 5,579,447 to Salgado, the disclosure of which is incorporated herein
by reference, coordinates the operation of the scanner and printer in a
digital copying arrangement. In a digital copying arrangement, the scanner
18 (also referred to as image input terminal (IIT)) reads an image on an
original document by using a CCD full width array and converts analog
video signals, as gathered, into digital signals. In turn, an image
processing system (not shown), associated with the scanner 18, executes
signal correction and the like, converts the corrected signals into
multi-level signals (e.g. binary signals), compresses the multi-level
signals and preferably stores the same in electronic precollation (not
shown).
Referring to FIG. 2, the printer 20 (also referred to as image output
terminal (IOT)) preferably includes a xerographic print engine. In one
example, the print engine has a multi-pitch belt (not shown) which is
written on with an imaging source, such as a synchronous source (e.g.
laser raster output scanning device) or an asynchronous source (e.g. LED
print bar). In a printing context, the multi-level image data is read out
of the EPC memory, while the imaging source is turned on and off, in
accordance with the image data, forming a latent image on the
photoreceptor. In turn, the latent image is developed with, for example, a
hybrid jumping development technique and transferred to a print media
sheet. Upon fusing the resulting print, it may be inverted for duplexing
or simply outputted. It will be appreciated by those skilled in the art
that the printer can assume other forms besides a xerographic print engine
without altering the concept upon which the disclosed embodiment is based.
For example, the printing system 10 could be implemented with a thermal
ink jet or ionographic printer.
Referring to FIG. 3, the network service module 14 is discussed in further
detail. As will be recognized by those skilled in the art, the
architecture of the network service module is similar to that of a known
"PC clone". More particularly, in one example, a controller 44 assumes the
form of a SPARC processor, manufactured by Sun Microsystems, Inc., is
coupled with a standard SBus 72. In the illustrated embodiment of FIG. 3,
a host memory 74, which preferably assumes the form of DRAM, and a SCSI
disk drive device 76 are coupled operatively to the SBus 72. While not
shown in FIG. 3, a storage or I/O device could be coupled with the SBus
with a suitable interface chip. As further shown in FIG. 3, the SBus is
coupled with a network 78 by way of an appropriate network interface 80.
In one example, the network interface includes all of the hardware and
software necessary to relate the hardware/software components of the
controller 44 with the hardware/software components of the network 78. For
instance, to interface various protocols between the network service
module 14 and the network 78, the network interface could be provided
with, among other software, Netware.RTM. from Novell Corp.
In one example, the network 78 includes a client, such as a workstation 82
with an emitter or driver 84. In operation, a user may generate a job
including a plurality of electronic pages and a set of processing
instructions. In turn, the job is converted, with the emitter, into a
representation written in a page description language, such as PostScript.
The job is then transmitted to the controller 44 where it is interpreted
with a decomposer, such as one provided by Adobe Corporation. Some of the
principles underlying the concept of interpreting a PDL job are provided
in U.S. Pat. No. 5,493,634 to Bonk et al. and U.S. Pat. No. 5,226,112 to
Mensing et al., the disclosures of both references being incorporated
herein by reference. Further details regarding a technique for generating
a job in a PDL may be obtained by reference to the following text, the
pertinent portions of which are incorporated herein by reference:
PostScript.RTM. Language Reference Manual
Second Edition
Addison-Wesley Publishing Co.
1990
Referring to FIG. 4, a block diagram which further elaborates on the
network controller schematic of FIG. 3 is shown. In the illustrated
embodiment of FIG. 4, the clients 100 (each client, in FIG. 3, being shown
with a workstation 82 and an emitter 84) are configured with a variety of
protocols, such as LPD (a protocol for UNIX), Novell network protocol,
AppleTalk and DCS (a protocol for Xerox digital copiers known as the
"Document Centre Systems"). Additionally, each of the clients is
preferably provided with "browsing" capability which allows for
communication with an HTTP server for access to, among other locations,
the World Wide Web. The clients communicate with the network server or
electronic subsystem ("ESS") 14 by way of Connectivity Services (CS) 102.
As shown in FIG. 4, the ESS comprises two parts, namely a Microkernal 104
(more particularly, a partial abstract model of a Microkernal mapped into
a model based on DPA ISO 10175/POSIX IEEE 1003.7) and an application
specific subsystem 106.
In general, a network or point-to-point print submission originates at the
Protocol Services level of the (CS) subsystem. Each Protocol Service
listens on a well-known socket for a connection indication. When a
Protocol Service receives the connection indication it submits a job
request to the Connectivity Core. The Connectivity Core will translate
this request into a DPA-compatible format and forward it to a DM subsystem
108. When the job submission is granted, the Protocol Services can submit
one or more documents. Document submission is achieved by sending a
document request and an I/O descriptor to the Connectivity Core. This will
also be translated and forwarded to the DM subsystem.
After the document has been accepted, the Protocol Service starts to
receive data from the underlying protocol stack and writes it into the I/O
descriptor. This data will read on the other side of the I/O descriptor by
a consumer or will be spooled somewhere in the system. When the remote
client indicates that there is no more data, the I/O descriptor is closed
signaling the end of this specific document. After all documents have been
received, a job termination request is sent from the Protocol Services to
the Connectivity Core, which then forwards it to the DM. Eventually, this
request will be completed by the system, and the Protocol Service will
release all resources associated with the job.
Queries normally directed from a client (FIG. 4) to the printing machine 12
are processed by use of an HTTP server 107 operating in conjunction with
the DM subsystem 108, as discussed below in detail.
The Microkernel has a Document Management (DM) subsystem that performs most
of the DPA/POSIX Server functionality. The DM subsystem validates user
requests, queues requests, spools document data, schedules the job for the
device, and collects and maintains status information. The DM subsystem
extends the DPA/POSIX Server in some aspects, since it can be configured
to handle scan jobs (for filing or faxing) and copying jobs. DM provides
for document sniffing, spooling, and scheduling services. Service
providers, such as Document Processing 110 can register their services
with DM.
Document Processing (DP), which includes the Image Frame Store (IFS) and
the instantiation of at least one producer, is provided with the
Microkernel. DP processes documents into images (full frame buffers or
raster-scan bands, depending on the configuration of the Microkernel). The
Image Frame Store assigns producers to consumers.
Essentially, the Microkernal 104 can be thought of as a generic ESS while
the subsystem 106 can be thought of as an application specific ESS. That
is, the Microkernal 104 contains the fundamental building blocks of a
print server, while the subsystem 106 contains all of the software
components necessary to, in conjunction with the Microkernal 104, provide
the VCM 16 with a desired level of operability. More particularly, an
Agent, which filters out all commands/requests emanating from the
Microkernal 104, is designated with the numeral 114. Basically, the Agent
serves as a "hook" into the generic ESS to facilitate the handling of all
remote requests. The Agent works in conjunction with other services, such
as Print Services 116 and Diagnostics 118, to support the operation of the
VCM.
The Agent 114 also communicates with an ESS Query Utility 120 to maintain,
among other things, a composite queue, which composite queue is the basis
of copending U.S. patent application Ser. No. 08/786,466 filed by Grzenda
et al. on Jan. 21, 1997. While the functions of the Agent and the ESS
Query Utility could be combined, they are shown as separate here in a
modularized model. The ESS Query Utility also communicates with a
Scan-to-File process 122, which process facilitates the filing of
previously scanned documents to the network, as well as an
Accounting/Authorization/Authentication service ("AAA") 124. The AAA is
used, among other things to authorize the performance of certain acts
sought to be performed by a remote client. In one example, the AAA is
implemented with software of the type found in Xerox' DocuSP 1.0 print
server. As will appear, the AAA facilitates the preferred embodiment in
that it prevents the undesirable tampering of one or more queued jobs by
unauthorized system users. Additionally, as will appear, ESS Query Utility
120 can be used to obtain a host of information other than queue
information. For example, the Utility 120 can be employed to obtain both
machine configuration information (such as machine settings) as well as
status information relating to subsystems/processes other than the
queue(s).
Referring to the printing machine 12 aspect of FIG. 4, a Copy Service 128
communicates with the ESS Query Utility 120 and a VCM Queue Utility 130.
The Copy Service, which resides, in one example, on the controller 44
(FIG. 6) performs a function, on the copy side, comparable to the DM 108.
Among other things, the Copy Service, supervises the development of copy
and Fax jobs as well as the management of the VCM Queue. The VCM Queue
Utility communicates with and gathers queue related data from a Mark
Service 132 and a suitable User Interface 134. While the functions of the
User Interface and the VCM Queue Utility could be combined, they are shown
as separate here in a modularized model.
The Mark Service is associated with the printer 20 (FIGS. 2 and 3) and a
VCM Queue is associated with the User Interface, as on, for example, the
Xerox Document Centre 35 digital copier. As will be appreciated by those
skilled in the art, both of the Mark Service and the User Interface are
key components in developing and maintaining the VCM Queue. For example,
the complexion of the VCM Queue is constantly being altered as a result of
activity in the Mark Service, while a significant amount of control is
asserted on the VCM Queue as a function of communication with the User
Interface.
Referring still to FIG. 4, the HTTP server 107 further includes a common
gateway interface ("CGI") designated with the numeral 140. As discussed
above, the CGI, through use of suitable software, permits output
responsive to user provided parameters, to be communicated to the client
100. More particularly, in practice, a client user develops a query
(including a set of parameters) which requests an output from a remote
network system, such as the printing system 12. In one example, a request
may be made with respect to information regarding the order of jobs in a
queue or the current settings of the printing system. As will be
appreciated by those skilled in the art, a query may be directed toward a
wide range of information associated with the printing system and the
remote network system being queried could include a system other than a
printing system--for instance, the remote network system could include a
stand-alone scanning device.
Referring now to FIG. 5, the HTTP server 107 with its related CGI 140 are
shown in greater detail. As shown in the illustrated embodiment of FIG. 5,
the CGI 140 includes a CGI script 142 communicating with a query parser
144. In particular, the CGI script informs the parser as to the
information requested by way of an incoming query. The query parser
communicates with a set of files Q(i) which may, in one example, be stored
in mass memory 76 (FIG. 3). Preferably, each file, as will appear, is
formatted as an extended HTML file. Additionally, the query parser 144
communicates with a query resolver 146, which query resolver "looks to"
the document manager 108 for pertinent dynamic information called for by a
query. The query resolver communicates with the formatter 148 for passing
the dynamic information thereto. Output of the query parser 144 and the
formatter 148 are relayed to the HTTP server 107.
To appreciate the problem solved by the preferred embodiment, reference is
made to FIGS. 6A and 6B. In the prior art, as illustrated in FIG. 6A, an
HTTP server communicates with the CGI, which CGI includes a plurality of
programs or "scripts". A first program facilitates acquisition of a first
type of query information (e.g. information regarding the jobs currently
residing in a print queue of the printing system 12 (FIG. 4)), a second
program facilitates acquisition of a second type of query information
(e.g. machine settings for the printing system 12), and so on. In prior
art systems, a response to a query, as shown on a "web page" includes
certain idenitfying information (e.g. source of data), referred to as
"static" information and other "dynamic" information showing a current
state of a subsystem with which the query corresponds. In one example, the
dynamic information may comprise current state information from a target
queue.
The following example is provided to convey one known approach for
developing the web page in the prior art arrangement of FIG. 6A. In
particular, it may be desired to create a web page with the following
information:
StaA
StaB
DyInfo
StaC
where "Sta--" indicates that the information to be displayed is static, and
"DyInfo" indicates that the information to be displayed is dynamic.
In the illustrated embodiment of FIG. 6A, the above page is generated by
way of the following scheme wich includes the following instructions:
Print StaA
Print StaB
Get DyInfo
Print DyInfo
Print StaC
where the term "Print" is used in a sense comparable with "writing."
It should be appreciated that the above page printing/writing scheme is
specific to the particular query to which it relates. That is, while the
above printing scheme may be suitable for writing a web page showing the
current state of a queue, it is not necessarily appropriate for writing a
web page showing machine settings since certain static information for the
queue web page will not be the same as certain static information for the
machine settings web page. For example, information, such as "StaB" may
not relate to the machine settings web page at all. Moreover, the order of
information presentation tends to vary among query based web pages to be
displayed. Accordingly, it is understood that separate programs must be
written to correspond respectively with separate queries. This is
disadvantageous in that writing a program for each query can be time
consuming.
Referring to FIGS. 5 and 6B, an approach, in which one program is used in
conjunction with multiple files, is discussed. Referring first to FIG. 6B,
the query parser 144 is corresponded with a plurality of files 152, which
files are stored in a suitable memory location, such as disk 76 (FIGS. 3
and 5). Each file 152 (i.e. file 1, file 2, . . . file n) is associated
with a particular set of static information required to generate a web
page for a corresponding query as well as the marker designating where the
dynamic state information is to be placed on the web page. For instance,
file 1 may include all of the static information required to fill out the
static information portion(s) of a queue web page.
Referring still to FIG. 6B, further discussion with respect to the extended
HTML is provided. Preferably, the query parser is provided with the
following parsing program (including the following instructions):
______________________________________
Copy File Q(i)
If <Dynamic>
Get DyInfo
Print DyInfo
Return
______________________________________
where Q(i) corresponds with a file having the set of information with which
the pending query is associated, e.g. Q(1) corresponds with a queue web
page file having a marker or indicator for designating the presence of
queue state information along with static information, Q(2) corresponds
with a machine settings web page file having an indicator designating the
presence of machine setting state information along with static
information for a machine settings web page, and so on; and
"<Dynamic>" serves as an indicator that the corresponding web page display
is at a point of development where DyInfo is required.
The roles of Q(i) and <Dynamic> will be more fully appreciated in view of
the following discussion:
Referring to FIG. 5, preferably a selected query is transmitted from the
client 100 (FIG. 4) to the HTTP server 107 which invokes the CGI script
142. In turn, the CGI script imparts to the query parser 144 what type of
query is to be processed. In turn, the parser uses its program to initiate
the copying of regular HTML, i.e. static information, to the HTTP server
for relay of information to the client. That is, referring to the copy
aspect of the above-shown template, information is copied out of the
appropriate Q(i) (in other words, one of the files 152) and provided, by
way of the query parser to the HTTP server. When the query parser 144
parses the information of the file referred to above as "<dynamic>", a
demand for the corresponding dynamic information is transmitted to the
query resolver 146. The query resolver, in turn, requests of the document
manager 108 that the appropriate dynamic information be retrieved from the
printing system 12 or the network module 14. The manner in which the
document manager obtain dynamic information from the printing system or
network module should appear from the discussion of FIG. 4 above. In
response to the request of the query resolver, the document manager
communicates requested dynamic information to the query resolver, which
query resolver passes along the dynamic information to the formatter 148.
It should be appreciated that writing a program to obtain the dynamic
information, e.g. state information, can be rather cumbersome in that the
amount of information to be obtained can be substantial, thus requiring a
retrieval program with a relatively large number of commands. In practice,
a "shorthand" expression is used by the document manager 108 to retrieve
dynamic information. In the example of retrieving state information for
jobs in a queue, a format statement, analogous to a format statement used
in Fortran, is employed to fetch such state information. Preferably, the
shorthand or format type statement indicates the query type, e.g.
query="list jobs", provides a range of state values to be obtained, e.g.
fmt=<tr><de="%1"> . . . ">, and designates other certain discrete
information to be obtained, e.g. "job name", "owner" and so on.
In using this sort of shorthand, all of the necessary information is
retrieved by the document manager and provided to the formatter 148. In
turn, the formatter causes the retrieved information to be written at the
HTTP server 107 in a presentable form for use in the web page ultimately
provided to the client. As will be appreciated b | | |
