JP3947136B2 - Web service system, flow development support device, and flow development support program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a web service system that provides a web service by developing a web service flow by combining a plurality of unit flows that define some processes of the web service flow, and a flow that individually executes the unit flow. The present invention relates to a flow development support device and a flow development support program for supporting development of a web service flow by an execution device.
[0002]
[Prior art]
In recent years, with the progress of information processing technology, new mechanisms that can call and use application programs provided in an in-company information system and an inter-company commerce system via a network and receive calculation results are spreading. Such a mechanism is called a web service (Web service), and is realized by using open technologies such as the Web and XML (extensible markup language). The three specifications, SOAP (simple object access protocol), WSDL (web services description language), and UDDI (universal description, discovery and integration), which are currently standardized, are the most basic operations of Web services. Service description, discovery, and invocation are realized. By using these technologies, one-to-one cooperation between a Web service user and a Web service provider becomes possible.
[0003]
However, in-company information systems and inter-company commerce systems require more complex system linkages. There is a strong demand for research and development of new software technologies to achieve this. One of them is a mechanism that organizes calls to multiple Web services as business processes and workflows. Currently, BPEL4WS (business process execution language for web services), WSFL (web services flow language), XLANG, WSCI, BPML (business) are standard languages for describing web service flows that define calling procedures for multiple web services. Many proposals such as process modeling language have been made. In these Web service flow description languages, one logical Web service flow is defined as one Web service flow description (see Non-Patent Document 1 to Non-Patent Document 6).
[0004]
[Non-Patent Document 1]
"Behavior description mechanism for Web service composition", Journal of Artificial Intelligence, vol.17, no.4, 2002.
[0005]
[Non-Patent Document 2]
`` Web Services Architecture Overview '', http://www-6.ibm.com/jp/developerworks/webservices/001201/j_w-ovr.html
[0006]
[Non-Patent Document 3]
"Web Services Architect: Part 1: Introduction to Dynamic e-business", http://www-6.ibm.com/developerworks/webservices/010608/j_ws-arc1.html
[0007]
[Non-Patent Document 4]
"Business Processes with BPEL4WS: About BPEL4WS, Part 1", http://www-6.ibm.com/developerworks/webservices/021025/j_ws-bpelcol1.html
[0008]
[Non-Patent Document 5]
"Business Process Execution Language for Web Services, Version 1.0", http://www-106.ibm.com/developerworks/webservices/library/ws-bpel/,2002
[0009]
[Non-Patent Document 6]
Web Services Description Language (WSDL) Version 1.2, http://www.w3.org/TR/2003/WD-wsdl12-20030124/,2003
[0010]
[Problems to be solved by the invention]
However, in a large-scale business process, there is a strong demand for switching the Web service to be called according to the execution status of the process. In the case of the above Web service flow description language, conditional statements must be frequently used in the Web service flow to describe Web service selection. As a result, the definition of control statements and individual Web service call processing definitions is relatively higher than the semantic processing originally intended to be realized in the Web service flow, and the description is complicated and the Web service flow definition is unpredictable. It has become.
[0011]
The present invention has been made in consideration of such circumstances, and the object of the present invention is to flexibly combine unit flows for performing relatively small processing, and to create a logical web as a whole. The object is to provide a web service system capable of dynamically assembling service flows to realize a web service. Therefore, another object is to provide a flow development support apparatus and a flow development support program that can efficiently support the development of a web service flow by a flow execution apparatus that individually executes a unit flow.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, a web service system of the present invention includes a plurality of web service providing apparatuses that individually provide a plurality of web services having the same plan name, and a plurality of processes that use the web service. A flow execution device that individually executes processing corresponding to a plurality of unit flows each indicating a processing procedure; and the unit flow that indicates the plan name of the web service and the processing procedure that uses the web service. A plan storage device that stores plan information in which a flow name and a precondition including a plurality of variables are associated, a state storage device that stores state information indicating an execution state of the process in the flow execution device, and a flow A unit support unit that is provided in the flow execution device and selected in response to a request from the user terminal. Means for outputting a call request including the plan name to the flow development support device when the flow call by the plan name is included in the flow development support device, and receiving the call request, Means for storing in the state storage device as the state information data for handing over to the flow execution device indicated in the call request; and the plan name provided in the flow development support device and indicated in the call request. The plan information including the preconditions that can be substituted for all variables including the data stored in the state storage device is selected from the plan storage device and indicated in the selected plan information Means for outputting an execution request indicating the flow name to the flow execution device; and provided in the flow execution device; Means for outputting first execution result information obtained by execution of a unit flow having the flow name indicated in the execution request to the flow development support apparatus as a reply to the execution request; Provided in the support apparatus, provided with the means for inputting the first execution result information and outputting the input first execution result information to the flow execution apparatus as an answer to the call request; The second execution result information is generated by executing the process indicated in the unit flow including the flow call using the first execution result information output from the flow development support apparatus. And means for outputting the second execution result information to the user terminal as an answer to the request from the user terminal.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of a Web service system according to the present embodiment.
[0015]
A Web service flow is a document that defines the calling order for Web services. The simplest web service flow is one that reads a series of web services sequentially. In a more complex Web service flow, it is possible to select a Web service or define a process for calling multiple Web services in parallel.
[0016]
The Web service system of this embodiment is divided into a large-level flow that defines a semantic processing flow in advance and a small-level flow that defines an individual processing implementation method, The present invention provides a mechanism capable of dynamically assembling and executing a logical web service flow as a whole by appropriately calling a lower-level flow required by a higher-level flow at the time of execution. Specifically, as a low-level flow, procedures for performing individual processes such as airline seat search, airline seat reservation, accommodation facility vacancy search, or accommodation facility reservation, etc. By assembling and executing a Web service flow that creates a travel plan by combining a small level flow according to a flow of a size level by defining a procedure for creating a travel plan as a level flow. .
[0017]
This Web service system includes a flow development support device 1, a flow execution device 2, a user terminal 3, and service providing hosts 4-1, 4-2, 4-3,. The flow development support device 1, the flow execution device 2, the user terminal 3, and the service providing hosts 4-1, 4-2, 4-3... Can communicate with each other via the Internet 5.
[0018]
The flow development support apparatus 1 supports the flow execution apparatus 2 to develop a Web service flow. The flow execution device 2 has a plurality of unit flows 21 corresponding to the above-described large level flow and small level flow, and executes the unit flows 21 individually. The unit flow 21 is, for example, a process of accessing a website provided by an airline company via the Internet 5 and performing a seat search for the airline company. When the flow execution apparatus 2 receives the request including the Web service flow name via the Internet 5, the flow execution apparatus 2 executes the designated unit flow 21 and returns the result to the request source. As an example of an application program that realizes such a flow execution apparatus 2, BPWS4J (business process execution language for web services Java (TM) run time) manufactured by IBM, WebSphere Application Server, and the like are known.
[0019]
The user terminal 3 is a computer terminal having a function of accessing the Internet 5. The user terminal 3 performs interface processing for a user who wants to receive a Web service. That is, for example, the user terminal 3 sends an execution request to the flow execution device 2 according to a user operation, or presents a result returned from the flow execution device 2 to the user.
[0020]
The service providing hosts 4-1, 4-2, 4-3.
[0021]
FIG. 2 is a block diagram showing the configuration of the flow development support apparatus 1.
As shown in FIG. 2, the flow development support apparatus 1 includes a plan list 11, an execution state database 12, and a support processing unit 13.
The flow development support device 1 can use, for example, a general-purpose server device or computer device as basic hardware. The support processing unit 13 can be realized by causing a processor mounted on the server device or the computer device to execute a flow development support program. At this time, the support processing unit 13 may be realized by installing the above-described flow development support program in a server device or a computer device in advance, or may be recorded on a removable recording medium such as a CD-ROM, or The flow development support program may be distributed via a network, and the flow development support program may be appropriately installed in a server device or a computer device. The plan list 11 and the execution state database 12 include a storage device such as a memory or a hard disk device built in the server device or computer device, or a storage device such as a memory or a hard disk device externally attached to the server device or computer device. Further, it can be realized by appropriately using a removable recording medium such as a floppy (R) disk.
[0022]
The plan list 11 holds a plurality of pieces of plan information (hereinafter referred to as plans) describing rule information (meta information) for developing a Web service flow.
[0023]
The execution state database 12 holds the execution state of the Web service flow.
[0024]
The support processing unit 13 further includes a request input unit 13a, an extraction unit 13b, a selection unit 13c, an output unit 13d, a response input unit 13e, a notification unit 13f, and an update unit 13g.
[0025]
The request input unit 13 a inputs a flow development request output from the flow execution device 2 via the Internet 5. The flow development request includes a plan name and data. The request input unit 13a outputs the plan name included in the input flow development request to the extraction unit 13b, and outputs the data to the update unit 13g.
[0026]
The extraction unit 13b includes a plan list including a plan name that includes the same plan name as the plan name output from the request input unit 13a and has a precondition having a predetermined relationship with the execution state stored in the execution state database 12. Extract all from 11. The extraction unit 13b outputs the extracted plan to the selection unit 13c. If the extraction unit 13b cannot extract the corresponding plan, the extraction unit 13b notifies the notification unit 13f to that effect.
[0027]
The selection unit 13c selects one of the plans output from the extraction unit 13b. The selection unit 13c outputs the selected one plan to the output unit 13d and the update unit 13g.
[0028]
The output unit 13d sends the execution request for the unit flow indicated in the plan output from the selection unit 13c to the flow execution apparatus 2 and sends it to the Internet 5.
[0029]
The response input unit 13 e inputs execution result information output from the flow execution device 2 as a result of executing the unit flow based on the execution request output from the output unit 13 d via the Internet 5. The response input unit 13e outputs the input execution result information to the notification unit 13f and the update unit 13g.
[0030]
The notification unit 13f creates result notification information including the execution result information output from the response input unit 13e, and sends this result notification information to the flow execution device 2 to the Internet 5.
[0031]
The update unit 13g stores in the execution state database 12 based on the data output from the request input unit 13a, the post-conditions included in the plan output from the selection unit 13c, or the execution result information output from the response input unit 13e. Updated information.
[0032]
Next, the operation of the Web service system configured as described above will be described.
Here, it is assumed that the service providing hosts 4-1, 4-2, and 4-3 provide a web service for vacant seat search and seat reservation for the airlines AIR1, AIR2, and AIR3. One of the unit flows 21 included in the flow execution device 2 is assumed to describe processing for creating a travel plan in response to a request from the user. Hereinafter, this unit flow 21 is referred to as a travel plan creation flow. Assume that three of the unit flows 21 describe a process of searching for vacant seats using Web services provided by the service providing hosts 4-1, 4-2, and 4-3, respectively. Hereinafter, these unit flows 21 are referred to as vacant seat search flows.
[0033]
FIG. 3 is a diagram showing the flow of information between the components of the Web service system, omitting the Internet 5.
As described above, the flow execution device 2 has the travel plan creation flow 21-1 and the vacant seat search flows 21-2, 21-3, and 21-4.
[0034]
The execution state database 12 may be empty as an initial state, that is, may have no execution state, or one or a plurality of states may be registered in advance. The state in the execution state database 12 is deleted or newly added by an operation from the update unit 13g as the execution of the support processing unit 13 proceeds. Each state is held in a data format called a predicate described below.
[0035]
The predicate is described below. As an example, consider the sentence “Narita is the departure place”. This sentence indicates that the individual “Narita” has the property of “being a departure place”. Here, the symbol `` NARITA '' is given to the subject `` Narita '', the symbol `` FROM '' is given to the sentence predicate `` is the departure place '', and the sentence `` Narita is the departure place '' is given as `` FROM ( NARITA) ”. This expression “FROM (NARITA)” is called a predicate, and “FROM” is called a predicate symbol. “FROM (NARITA)” indicates that the individual “Narita” is the starting point, but to express that the unspecified individual is the starting point, the variable “from” is used to indicate “FROM (from) ". A predicate having a plurality of arguments is expressed as “predicate symbol (argument 1, argument 2,...)”. Therefore, for example, the relationship that the character string “1234567” is the “ID” of the mile account of the airline “AIR1” is expressed as “ID (AIR1, 1234567)” using the predicate symbol “ID”.
[0036]
Here, predicates used to describe specific examples in the present embodiment are listed below, and the meanings represented by the respective predicates are briefly described.
[0037]
-FROM (from): from is the departure place.
[0038]
-TO (to): to is the destination.
[0039]
-DATE (date): date is the boarding date.
[0040]
-ID (airline, id): The character string id is the mileage account ID of the airline airline.
[0041]
-AVAILABLE (flight): Flight flight has vacant seats.
[0042]
-BEL (u, P): User u believes in predicate P.
[0043]
FIG. 4 is a diagram illustrating an example of the execution state database 12. The execution state database 12 shown in FIG. 4 has three states, “BEL (NAGANO, ID (AIR1, 1234567))”, “BEL (HASEGAWA, ID (AIR2, 111222333))”, “BEL (OHSUGA, ID (AIR2 , 444555666)) ”. For example, “BEL (NAGANO, ID (AIR1, 1234567))” [the user “NAGANO” believes that the character string “1234567” is the mile account ID of the airline “AIR1”. ] Information.
[0044]
A plan is registered in advance in the plan list 11.
The above plan is composed of five items: a plan ID, a plan name, a precondition, a flow call, and a post condition. The plan ID is a unique identifier in the plan list 11. The plan name is a character string representing the name of the plan, and the same plan name may be defined for a plurality of different plans. The precondition is a necessary condition for selecting a plan, and is described in a predicate format. The flow call defines information for requesting the flow execution device 2 to execute the unit flow, and the flow name for identifying the unit flow held by the flow execution device 2 and its unit Specify the three types of argument data to be passed to the flow and the variable that stores the data received as a result of the request. The post-condition is a condition as an effect of selecting a plan and calling a unit flow, and is described in a predicate format.
[0045]
FIG. 5 is a diagram showing an example of the plan list 11. The plan list 11 shown in FIG. 5 holds three plans, and the plan IDs are “plan1”, “plan2”, and “plan3” in order from the top. In both cases, the same plan name “search” is defined. These three plans correspond to vacant seat search flows 21-2, 21-3, and 21-4, respectively. “Search” is a plan name assigned to the vacant seat search.
[0046]
Hereinafter, taking the plan with the plan ID “plan1” as an example, its definition will be described in detail.
[0047]
The plan name is “search”.
[0048]
The preconditions are as follows.
BEL (u, FROM (from)) ∧
BEL (u, TO (to)) ∧
BEL (u, DATE (date)) ∧
BEL (u, ID (AIR1, number)
This precondition is expressed as a logical product (AND operation) of the following four predicates.
BEL (u, FROM (from))
BEL (u, TO (to))
BEL (u, DATE (date))
BEL (u, ID (AIR1, number))
That is, the following conditions are expressed.
User u believes from is the departure place, and
User u believes to is the destination, and
User u believes that date is the boarding date and time, and
User u believes that string number is the mile account ID of airline AIR1.
[0049]
The flow call is as follows.
flight = call ("AIR1 Search Service Flow", from, to, date, id)
That is, a unit flow whose flow name for identifying the vacant seat search service of the airline AIR1 is “AIR1 Search Service Flow” is called, and four argument data, from, to, date, id are passed and received as a result of the call. It represents storing data in the variable flight.
[0050]
The post-conditions are as follows.
[0051]
BEL (u, AVAILABLE (flight)) ∧
BEL (u, ID (AIR1, number))
This condition expresses that [user u believes that flight flight has vacant seats].
[0052]
FIG. 6 is a sequence diagram regarding execution of a Web service flow for creating a travel plan.
[0053]
Now, it is assumed that the user performs an operation for requesting the creation of a travel plan after accessing the flow execution device 2 by the user terminal 3. At this time, as shown in FIG. 6, an execution request 61 of a travel plan creation flow 21-1 is sent from the user terminal 3 to the flow execution device 2. In the travel plan creation flow 21-1, the procedure for creating a travel plan is defined, such as “Flight seat search → Air seat reservation → Accommodation vacancy search…”. Is not defined. Therefore, the travel plan creation flow 21-1 sends a flow development request 62 indicating a plan name “search” corresponding to “vacant flight seat search” to the flow development support apparatus 1. The flow development request 62 includes a user ID, data for delivery to another unit flow 21, and the like.
[0054]
When the flow development support apparatus 1 receives the flow development request 62, the plan name, user ID, and data to be delivered to another flow execution unit indicated in the flow development request are input by the request input unit 13a. Then, in response to the request input unit 13a inputting the various information as described above, the support processing unit 13 starts an inference process as shown in FIG.
[0055]
The user ID is an identifier representing the user, and for example, a user name is designated. The data is represented by a set of parameter name and value, and either one set or a plurality of sets may be transferred.
[0056]
FIG. 7 is a flowchart of the inference process.
In step ST1, the request input unit 13a receives the plan name and user ID output from the flow execution unit 2a as described above, and data for delivery to another flow execution unit.
[0057]
In step ST2, the update unit 13g generates predicate data in which the parameter name is a predicate symbol and the value is set as an argument of the predicate for the data received by the request input unit 13a, and the predicate data is executed in the execution state database. 12 is registered. For example, when the request input unit 13a receives data including “NAGANO” as the user ID, the parameter name “FROM”, and the value “NARITA” as the input regarding the departure place, the update unit 13g receives the predicate data “BEL”. (NAGANO, FROM (NARITA)) "is generated and registered in the execution state database 12.
[0058]
In step ST3, the extraction unit 13b has the same plan name as that entered in the request input unit 13a from the plan list 11 and can use a predicate in the execution state database 12 to unify preconditions. Search for p. Note that a plan that can be unified refers to a plan that can find a predicate having values that can be assigned to all variables included in the predicate.
[0059]
In step ST4, the extraction unit 13b confirms whether the plan p exists.
If the plan p exists, the plan p extracted by the extraction unit 13b is passed to the selection unit 13c, and the process proceeds to step ST5.
[0060]
In step ST5, the selection unit 13c selects one plan p. If only one plan p has been extracted by the extraction unit 13b, the selection unit 13c may select this one plan p. If a plurality of plans p are extracted by the extraction unit 13b, they may be selected based on some appropriate criterion. For example, there is a technique such as selecting the first discovered by the extraction unit 13b first, or selecting one having a large number of preconditions.
[0061]
In step ST6, the output unit 13d performs the unification obtained in step ST3 with respect to the plan p selected by the selection unit 13c, that is, the variable between the flow call and the postcondition defined in the plan p. Apply to
[0062]
In step ST7, the output unit 13d calls the flow execution device 2, and sends an execution request including the flow name of the unit flow included in the flow call obtained in step ST6 and data to be delivered to the unit flow.
[0063]
For example, as the unit flow 21 corresponding to the plan name “search”, there are three vacant seat search flows 21-2, 21-3, and 21-4. Of these, the vacant seat search flow 21-2 is selected. If so, an execution request 63 is sent from the output unit 13d to the vacant seat search flow 21-2 as shown in FIGS.
[0064]
If this execution request is received, the flow execution apparatus 2 executes the unit flow having the flow name indicated in the execution request. As a result, in the above example, the vacant seat search flow 21-2 is started. The vacancy search flow 21-2 describes a procedure for searching for a vacancy by using a Web service provided by the service providing host 4-1. Accordingly, the vacant seat search flow 21-2 sends a vacant seat search request 64 to the service providing host 4-1, as shown in FIG. 6, and receives vacant seat information 65 returned from the service providing host 4-1 as a response to this request. Furthermore, the vacant seat search flow 21-2 sends the execution result information 66 including the vacant seat information 65 to the flow development support apparatus 1 as a response to the execution request 63 as shown in FIG. The execution result information 66 is input to the response input unit 13e in the flow development support apparatus 1.
[0065]
In the support processing unit 13, after the output unit 13d outputs the execution request in step ST7 in FIG. 7, the process proceeds to step ST8. In step ST8, the response input unit 13e confirms whether or not the execution request has been normally completed. If the execution request ends normally, the process proceeds to step ST9.
[0066]
In step ST9, the update unit 13g substitutes the execution result information 66 received by the response input unit 13e into a variable designated by the flow call of the plan p. If the same predicate exists in the unified postcondition, the update unit 13g also substitutes the execution result information 66 for the predicate.
[0067]
In step ST10, the update unit 13g deletes each predicate included in the precondition unified in step ST6 from the execution state database 12, and then executes each predicate included in the postcondition unified in step ST9. Register in the database 12.
[0068]
Finally, in step ST11, the notification unit 13f receives the result notification information 67 indicating the contents of the execution result information 66 received by the response input unit 13e as a response to the flow development request 62 as shown in FIG. Send to 21-1.
[0069]
If the plan p cannot be found in step ST3 in FIG. 7, the process proceeds from step ST4 to step ST11. If the execution request ends abnormally, the process proceeds from step ST8 to step ST11. In these cases, in step ST11, the notification unit 13f indicates that the result notification information 67 has failed in the flow development.
[0070]
Thereafter, air ticket reservations, accommodation vacancy searches, and the like are sequentially performed in the same manner as described above. Then, a travel plan creation flow 21-1 creates a travel plan based on various information obtained by these processes. Execution result information 68 indicating this travel plan is sent from the travel plan creation flow 21-1 to the user terminal 3 as a response to the execution request 61 as shown in FIG.
[0071]
Next, the operation of the flow development support apparatus 1 will be described in more detail.
First, in the flow development request 62, the plan name “search”, the user ID “NAGANO”, and the data “(FROM, NARITA), (TO, ITAMI), (DATE, 2003/04/0110: 00)” are shown. Suppose that
[0072]
The updating unit 13g receives the predicate “BEL (NAGANO, FROM (NARITA))” from the data “(FROM, NARITA)” and the predicate “BEL (NAGANO, TO (ITAMI))” from the data “(TO, ITAMI)”. , “BEL (NAGANO, DATE (2003/04/01 10:00))” is generated from the data “(DATE, 2003/04/01 10:00)” and registered in the execution state database 12. At this time, the execution state database 12 is updated to the state shown in FIG. 8 by increasing three predicates from the state shown in FIG.
[0073]
On the other hand, the extraction unit 13b searches for a plan p having the plan name “search” and using a predicate in the execution state database 12 to unify preconditions.
Here, there are three plans having the plan name “search”: “plan1”, “plan2”, and “plan3”.
[0074]
The pre-conditions for “plan1” are as follows.
BEL (u, FROM (from)) ∧
BEL (u, TO (to)) ∧
BEL (u, DATE (date)) ∧
BEL (u, ID (AIR1, number))
In comparison with the execution state database 12 shown in FIG. 8, it can be seen that the assignment to all the following five variables can be unified.
u = NAGANO
from = NARITA
to ＝ ITAMI
date = 2003/04/01 10:00
number = 1234567
At this time, the unified precondition is as follows.
BEL (NAGANO, FROM (NARITA)) ∧
BEL (NAGANO, TO (ITAMI)) ∧
BEL (NAGANO, DATE (2003/04/01 10:00)) ∧
BEL (NAGANO, ID (AIR1, 1234567))
These unified preconditions coincide with each predicate in the execution state database 12. Therefore, “plan1” is a candidate for plan p.
[0075]
The pre-conditions for “plan2” are as follows.
BEL (u, FROM (from)) ∧
BEL (u, TO (to)) ∧
BEL (u, DATE (date)) ∧
BEL (u, ID (AIR2, number))
In comparison with the execution state database 12 shown in FIG. 8, the following four variables can be substituted, that is, unified.
u = NAGANO
from = NARITA
to ＝ ITAMI
date = 2003/04/01 10:00
However, since the predicate corresponding to “BEL (u, ID (AIR2, number))” does not exist in the execution state database 12, it cannot be assigned to the variable “number”. Therefore, “plan2” is not a candidate for plan p. Similarly, for “plan3”, since the predicate corresponding to “BEL (u, ID (AIR3, number))” does not exist in the execution state database 12, it cannot be assigned to the variable “number”. Therefore, “plan3” is not a candidate for plan p.
[0076]
As described above, the extraction unit 13b extracts “plan1” as the plan p.
At this time, since only one plan has been extracted, the selection unit 13c selects the above “plan1” as it is.
[0077]
The output unit 13d applies the unification with respect to the precondition of “plan1” to the flow call and postcondition of “plan1”. The flow call for “plan1” is as follows.
flight = call ("AIR1 Search Service Flow", from, to, date, number)
When unification is applied to this flow call, the result is as follows.
flight = call ("AIR1 Search Service Flow", NARITA, ITAMI, 2003/04/01 10:00, 1234567)
The post-conditions are as follows.
BEL (u, AVAILABLE (flight)) ∧
BEL (u, ID (AIR1, number)
When unification is applied to this post-condition, it becomes as follows.
BEL (NAGANO, AVAILABLE (flight)) ∧
BEL (NAGANO, ID (AIR1, 1234567)
The variable “flight” is left as a variable at this stage.
[0078]
Next, the output unit 13 d sends an execution request 63 to the flow execution device 2. The execution request 63 includes the web service flow name “AIR1 Search Service Flow” and the four data “NARITA”, “ITAMI”, “2003/04/01 10:00” from the above unified flow call. , “1234567”. "AIR1 Search Service Flow"
Web service flow name assigned to vacancy search flow 21-2. For this reason, the vacancy search flow 21-2 is activated by the execution request 63.
[0079]
Assume that vacant seat flight "AIR1-079" is found by vacancy search flow 21-2. In this case, the execution result information 66 including this “AIR1-079” is returned from the vacant seat search flow 21-2. The execution result information 66 is input by the response input unit 13e and transferred to the update unit 13g. In the update unit 13g, the above-mentioned “AIR1-079” included in the execution result information 66 is substituted into the unified variable “flight” of the flow call.
Therefore, the value of the variable “flight” is “AIR1-079”. At this time, the above-described unified post-conditions are as follows.
BEL (NAGANO, AVAILABLE (AIR1-079)) ∧
BEL (NAGANO, ID (AIR1, 1234567)
Subsequently, the update unit 13g deletes the next data from the execution state database 12.
BEL (NAGANO, FROM (NARITA))
BEL (NAGANO, TO (ITAMI))
BEL (NAGANO, DATE (2003/04/01 10:00))
BEL (NAGANO, ID (AIR1, 1234567))
At the same time, the updating unit 13g adds the following two predicates included in the unified post-condition described above to the execution state database 12.
BEL (NAGANO, AVAILABLE (AIR1-079))
BEL (NAGANO, ID (AIR1, 1234567)
Therefore, the execution state database 12 is updated from the state of FIG. 8 to the state of FIG.
Finally, the notification unit 13f sends the result notification information 67 indicating “AIR1-079” to the travel plan creation flow 21-1, which is the caller.
[0080]
As described above, according to the present embodiment, each time the flow development support apparatus 1 receives a flow development request, the flow development support apparatus 1 selects one appropriate unit flow 21 according to the request and requests execution of the unit flow 21. . Further, the flow development support apparatus 1 returns information obtained as a result of executing the requested unit flow 21 to the unit flow 21 of the flow development request source. Therefore, in the flow execution device 2, another unit flow 21 can be called indirectly from one unit flow 21. As a result, it is possible to construct and execute one logical Web service flow by flexibly combining a plurality of unit flows 21.
[0081]
Further, according to the present embodiment, for example, when a unit flow is newly added, the newly added unit flow can be used by updating the plan list 11. More specifically, if a unit flow that makes a call to the vacancy search web service of an airline called AIR4 is added, the plan name is “search” and the flow call is “flight = call (” AIR4 Search Service Flow By adding a plan “11”, “from”, “to”, “date”, “id”) to the plan list 11, the above-mentioned unit flow for planning a trip is modified from the old unit flow without any modification. It is possible to call and use the added unit flow. That is, according to the present embodiment, development of individual unit flows can be performed without considering details of other unit flows. Further, it is possible to easily extend the Web service flow by updating or adding some unit flows.
[0082]
Further, according to the present embodiment, the precondition is included in the plan, the execution state of the Web service flow is stored in the execution state database 12, and the precondition can be unified using the information in the execution state database 12. Since the plan is extracted, an appropriate unit flow can be executed according to the execution state of the Web service flow.
[0083]
This embodiment can be variously modified as follows.
The plan list 11 and the execution state database 12 may not be included in the flow development support apparatus 1. In that case, a communication means for accessing the plan list 11 and the execution state database 12 from the flow development support apparatus 1 is provided in the flow development support apparatus 1.
[0084]
The extraction of the plan from the plan list 11 may be performed based only on the plan name. In this case, the plan need not include preconditions and postconditions.
Further, the execution state database 12 becomes unnecessary.
[0085]
The update of the execution state database 12 does not have to consider the postcondition.
[0086]
The number of flow execution devices 2 is not necessarily one, and the unit flows 21 possessed by each of the plurality of flow execution devices 2 may be appropriately developed.
[0087]
The processing content indicated by each unit flow 21 may be arbitrary. And the unit flow 21 in which the interface process with the user terminal 3 is shown may use another unit flow 21 only once.
[0088]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
[0089]
【The invention's effect】
According to the present invention, it is possible to flexibly combine unit flows for performing relatively small processes and dynamically assemble and execute one logical web service flow as a whole.
[Brief description of the drawings]
FIG. 1 is a block diagram of a Web service system according to an embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration of the flow development support apparatus 1 in FIG.
FIG. 3 is a diagram showing a flow of information between each unit of the Web service system.
4 is a diagram showing an example of an execution state database 12 in FIG. 2. FIG.
5 is a diagram showing an example of the plan list 11 in FIG.
FIG. 6 is a sequence diagram regarding execution of a Web service flow for creating a travel plan.
FIG. 7 is a flowchart of inference processing.
FIG. 8 is a diagram showing an example of updating the execution state database 12 in FIG. 2;
FIG. 9 is a view showing an example of updating the execution state database 12 in FIG. 2;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Flow deployment assistance apparatus, 2 ... Flow execution apparatus, 2a, 2b ... Flow execution part, 11 ... Plan list, 12 ... Execution state database, 13 ... Support processing part, 13a ... Request input part, 13b ... Extraction part, 13c ... selection unit, 13d ... output unit, 13e ... response input unit, 13f ... notification unit, 13g ... update unit.

Claims (5)

A plurality of web service providing devices that individually provide a plurality of web services having the same plan name ;
A flow execution device that individually executes processes according to a plurality of unit flows each showing a procedure of a plurality of processes including a process of using the web service;
And plan storage device for storing the plan name and plan information associating the pre-conditions including a flow name and a plurality of variables of the unit flow showing a procedure of a process to utilize the web service in which the web service has ,
A state storage device for storing state information indicating an execution state of the process in the flow execution device;
A flow development support device,
further,
Wherein provided in the flow execution unit, the flow of the call request including the plan name if it contains flows call by the plan name into unit flow one selected in response to a request from the User chromatography The terminal expansion Means for outputting to the support device ;
Means provided in the flow development support device, and upon receipt of the call request, means for storing in the state storage device data for passing to the flow execution device indicated in the call request as the state information;
Provided in the flow expand support device, the plan name-containing Mikatsu shown before Kiko out request, the containing substitutable the preconditions the data stored in the state storage device for all variables Means for selecting one plan information from the plan storage device and outputting an execution request indicating the flow name indicated in the selected plan information to the flow execution device ;
The flow is provided in the flow execution device, a first execution result information obtained by the execution of the unit flow having the flow name indicated in the execution request among the plurality of unit flows as a reply to the execution request Means for outputting to the deployment support device ;
Means provided in the flow development support apparatus, for inputting the first execution result information, and outputting the input first execution result information to the flow execution apparatus as an answer to the call request;
Provided in the flow execution device, the previously executing SL by using the first execution result information output processing flow call is indicated in the unit flow that was included from the flow development support device And a means for outputting the second execution result information to the user terminal as a response to the request from the user terminal . It intended to assist the flow execution unit for individually executing the plurality of unit flow shown a plurality of processing procedures including processing using the Web service, the same plan name with the plurality of web services, each with its web A plan storage device that stores plan information in which a flow name of the unit flow indicating a processing procedure using a service and a precondition including a plurality of variables are associated with each other, and execution of the processing in the flow execution device A flow development support device accessible to a state storage device that stores state information indicating a state;
Means for inputting a call request indicating the plan name from the flow execution device;
Means for causing the state storage device to store data for delivery to the flow execution device indicated in the call request as the state information;
Select one of the plan information including the pre-condition that includes the plan name indicated in the call request and includes the preconditions that can substitute the data stored in the state storage means for all variables. And means for outputting an execution request indicating the flow name indicated in the selected plan information to the flow execution device;
Means for inputting execution result information as an answer to the execution request from the flow execution device;
And a means for outputting the execution result information as an answer to the call request to the flow execution apparatus. If the selected the plan information includes the post-conditions, including variables and the values and substitutable the data to the variable included in the execution result information the status information in a variable the posterior conditions The flow development support apparatus according to claim 2, further comprising means for updating to contents determined by substitution . A plan that stores plan information in which the same plan name that each of a plurality of web services has, the flow name of the unit flow that indicates the processing procedure for using the web service, and the preconditions that include a plurality of variables are associated with each other A computer capable of accessing a storage device and a state storage device that stores state information indicating an execution state of the process in the flow execution device;
Means for inputting a call request indicating the plan name from the flow execution device;
Means for causing the state storage device to store data for delivery to the flow execution device indicated in the call request as the state information;
Select one of the plan information including the pre-condition that includes the plan name indicated in the call request and includes the preconditions that can substitute the data stored in the state storage means for all variables. And means for outputting an execution request indicating the flow name indicated in the selected plan information to the flow execution device;
Means for inputting execution result information as an answer to the execution request from the flow execution device;
A flow development support program that functions as means for outputting the execution result information to the flow execution apparatus as an answer to the call request. When the selected post-plan information includes a post-condition including a variable , the state information includes a value included in the execution result information as the post-condition variable and the data that can be substituted into the variable. The flow development support program according to claim 4 , further causing the computer to function as means for updating to contents determined by substitution .

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