H5 webpage front-end and back-end local debugging method, device and medium for hybrid development of APPs

Abstract

The application discloses a kind of H5 web page front-end and back-end local debugging methods, equipment and medium of mixed development APP, wherein the method comprises: when mixed development APP carries out front-end and back-end local debugging, business back-end provides business interface to the H5 web page test front-end of mixed development APP;Common plug-in is introduced to H5 web page test front-end, and common plug-in sends first request to plug-in back-end through test interface, for request corresponding to user identity information Verification information, at least one user identity information is included in first request, and verification information is used to verify whether the business request sent by H5 web page test end to server meets the identity information security requirement of user;In response to first request, plug-in back-end generates verification information, and sends verification information to common plug-in;Common plug-in puts verification information into the cookie of H5 web page. Utilize the embodiment of the application can improve the efficiency of H5 web page of mixed development APP to carry out front-end and back-end local debugging.

Description

Technical Field

[0001] This invention relates to the field of Internet information technology, and in particular to a method for local front-end and back-end integration of H5 web pages for hybrid APP development, electronic devices, computer-readable storage media, and computer program products. Background Technology

[0002] HTML5 is a language for describing web content. It is the next-generation standard for the internet and a language for building and presenting internet content. It is considered one of the core technologies of the internet. Pages designed using HTML5 front-end technologies can be called H5 pages.

[0003] Hybrid development (Hybrid App development) refers to the use of a combination of native and HTML5 development technologies to improve efficiency and save costs when developing an app product. It usually consists of two parts: an HTML5 cloud website and an app application client.

[0004] Typically, when performing local integration testing of the H5 webpage for a hybrid app's test frontend and business backend, an additional test machine is required. This test machine is connected to the computer, an interface for debugging is accessed, and the hybrid app is opened on the test machine. The HTML page is placed within the app, and communication with the backend is achieved through the app and the debugging interface. The hybrid app then retrieves authentication information used to verify user identity. However, this integration testing method relies on a test machine and requires coordination of multiple devices, resulting in low efficiency.

[0005] In addition, regarding the front-end and back-end communication of H5 web pages in hybrid development apps after joint debugging, the H5 page often requests verification information from the client first, then transmits the verification information to the back-end, and the back-end then returns business data. However, in this process, the H5 page needs to wait for the client's protocol callback before requesting the business back-end, which increases the communication time between the front-end and back-end and reduces the loading efficiency of the H5 page. Summary of the Invention

[0006] In view of this, embodiments of this application provide a front-end and back-end communication method, electronic device, computer-readable storage medium, and computer program product for hybrid development of H5 web pages for APPs, to solve at least one technical problem.

[0007] This application provides a method for local front-end and back-end integration testing of an H5 webpage in a hybrid development APP, comprising: when the hybrid development APP is performing local front-end and back-end integration testing, the business back-end provides a business interface to the H5 webpage test front-end of the hybrid development APP; a common plugin is introduced into the H5 webpage test front-end, the common plugin sending a first request to the plugin back-end through the test interface to request verification information corresponding to user identity information, the first request including at least one user identity information, the verification information being used to verify whether the business request sent by the H5 webpage test front-end to the server complies with the user's identity information security requirements; in response to the first request, the plugin back-end generates verification information and sends the verification information to the common plugin, the common plugin placing the verification information in the H5 webpage's cookie; the H5 webpage test front-end sends an access request to the business back-end, the access request carrying the H5 webpage's cookie; the business back-end obtains the verification information from the H5 webpage's cookie from the received access request, verifies the verification information, and returns business data to the H5 webpage test front-end after successful verification, thus ending the integration testing.

[0008] Optionally, after the joint debugging is completed, the client of the hybrid development APP sends a second request to the server to request verification information corresponding to the current user's identity information. The verification information is used to verify whether the business request sent by the front end of the H5 webpage to the server meets the user's identity information security requirements. In response to the second request, the server sends the verification information to the client. The client stores the received verification information in the cookie of the H5 webpage. The front end of the H5 webpage sends an access request to the server, and the access request includes the cookie of the H5 webpage. The server obtains the verification information from the cookie of the H5 webpage from the received access request, and verifies the verification information. If the verification is successful, the loading of the H5 webpage is allowed.

[0009] Optionally, the verification information includes at least one of the following: user identity information, user login password, and verification code.

[0010] Optionally, the verification information is stored in a cookie as encrypted ciphertext.

[0011] Optionally, a gateway is set between the front end of the H5 webpage and the server; the server obtains the verification information from the cookie and verifies the verification information, including: the front end of the H5 webpage sends the verification information to the server through the gateway; the server obtains the verification information and verifies the verification information.

[0012] This application also proposes an electronic device, which includes a processor and a memory storing computer program instructions; when the electronic device executes the computer program instructions, it implements the method described above.

[0013] This application also proposes a computer-readable storage medium storing computer program instructions that, when executed by a processor, implement the method described above.

[0014] This application also proposes a computer program product, characterized in that it includes computer program instructions that, when executed by a processor, implement the method described above.

[0015] The front-end and back-end local integration testing method proposed in this application eliminates the need for a test machine for communication between the front-end and back-end of H5 web pages. Verification information can be directly obtained through the introduced public plugin and the test interface provided by the plugin's backend. This verification information is then placed in the H5 web page's cookie, enabling fast and efficient business communication between the front-end and back-end of H5 web page testing. Furthermore, the integration testing account information can be switched at any time. As the integration testing account information changes, the verification information in the public plugin will also automatically change. All of this is done in the background, and integration testing personnel only need to switch integration testing accounts to perform business integration testing under different account information, thus significantly improving integration testing efficiency. Attached Figure Description

[0016] The preferred embodiments of the present invention will now be described in further detail with reference to the accompanying drawings, wherein:

[0017] Figure 1 A schematic diagram of a system architecture according to an embodiment of this application is shown;

[0018] Figure 2 A flowchart illustrating the front-end and back-end local integration method for an H5 webpage of a hybrid development APP according to an embodiment of this application is shown.

[0019] Figure 3 This diagram illustrates the front-end and back-end communication process of an H5 webpage after the integration testing is completed according to an embodiment of this application.

[0020] Figure 4 This is a schematic diagram of an electronic device used to implement the methods of the embodiments of this application. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the following detailed description, reference can be made to the accompanying drawings, which form part of this application and illustrate specific embodiments of the present application. In the drawings, similar reference numerals describe substantially similar components in different figures. Specific embodiments of the present application are described in sufficient detail below to enable those skilled in the art to implement the technical solutions of the present application. It should be understood that other embodiments may also be utilized, or structural, logical, or electrical changes may be made to the embodiments of the present application.

[0023] The principles and spirit of this application will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided to make the principles and spirit of this application clearer and more thorough, enabling those skilled in the art to better understand and implement the principles and spirit of this application. The exemplary embodiments provided herein are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described herein without inventive effort are within the scope of protection of this application.

[0024] The embodiments of this application relate to terminal devices and / or servers. Those skilled in the art will understand that the embodiments of this application can be implemented as a system, apparatus, device, method, computer-readable storage medium, or computer program product. Therefore, this disclosure can be specifically implemented in at least one of the following forms: entirely hardware, entirely software, or a combination of hardware and software. According to the embodiments of this application, this application claims protection for a front-end and back-end communication method, electronic device, computer-readable storage medium, and computer program product for hybrid development of H5 web pages for APPs. Figure 1 A schematic diagram of a system architecture according to an embodiment of this application is shown. For example... Figure 1As shown, the system includes a terminal device 102 and a server 104. The terminal device 102 can include at least one of the following: a smartphone, tablet, laptop, desktop computer, smart TV, various wearable devices, augmented reality (AR) devices, virtual reality (VR) devices, etc. A client can be installed on the terminal device 102. For example, the client can be a client specifically designed to perform a particular function (such as an application app), or a client with multiple embedded application applets (with different functions), or a client logged in via a browser. Users can operate on the terminal device 102. For example, a user can open the client installed on the terminal device 102 and input commands through the client, or a user can open the browser installed on the terminal device 102 and input commands through the browser. After receiving the user's input command, the terminal device 102 sends a request message containing the command to the server 104. After receiving the request message, the server 104 performs the corresponding processing and then returns the processing result information to the terminal device 102. The user command is completed through a series of data processing and information interaction.

[0025] In this document, terms such as first, second, and third are used only to distinguish one entity (or operation) from another, and are not intended to require or imply any order or relationship between these entities (or operations).

[0026] Figure 2 The diagram illustrates a flowchart of a method for local front-end and back-end integration testing of an H5 webpage for a hybrid development app according to an embodiment of this application. The method includes the following steps:

[0027] S101: When performing local front-end and back-end integration testing for a hybrid development APP, the business back-end provides business interfaces to the H5 webpage test front-end of the hybrid development APP;

[0028] S102: Introduce a public plugin to the H5 webpage test front end. The public plugin sends a first request to the plugin back end through the test interface to request verification information corresponding to the user's identity information. The first request includes at least one user identity information. The verification information is used to verify whether the business request sent by the H5 webpage test end to the server meets the user's identity information security requirements.

[0029] S103: In response to the first request, the plugin backend generates verification information and sends the verification information to the public plugin, which puts the verification information into the cookie of the H5 webpage;

[0030] S104: The H5 webpage test frontend sends an access request to the business backend, and the access request carries the H5 webpage cookie;

[0031] S105: The business backend obtains the verification information from the H5 webpage's cookie from the received access request, verifies the verification information, and returns business data to the H5 webpage test frontend after successful verification, thus ending the integration test.

[0032] According to an embodiment of this application, the public plugin has the function of calling a test interface to obtain verification information. The test interface is provided by the plugin backend and can be used for communication between the public plugin and the plugin backend. Before performing local front-end and back-end integration testing, the public plugin already has the ability to send requests to the plugin backend through the test interface. When the H5 webpage test frontend references the public plugin, the public plugin is activated and then actively sends a first request to the plugin backend to obtain verification information. After receiving the first request, the plugin backend sends the generated verification information to the public plugin, and the public plugin puts the verification information into the H5 webpage's cookie.

[0033] In this application, the plugin backend corresponds to the public plugin. The plugin backend operates in the background, controlling the content of the public plugin. The public plugin can send requests to the plugin backend, and the plugin backend can send response data to the public plugin based on those requests. In this application, the plugin backend and the public plugin communicate through a test interface. Requests sent by the public plugin are received by the plugin backend, and the plugin backend responds by returning data to the public plugin.

[0034] Specifically, the public plugin can send a first request to the plugin backend through the test interface to obtain verification information. The first request includes the identity information of at least one user. After receiving the user's identity information, the plugin backend will generate verification information.

[0035] In some embodiments, optionally, the user identity information is a username generated by the tester. After receiving the first request and the username, the plugin backend will generate verification information corresponding to the username. In some embodiments, optionally, the verification information has a time limit. Within the time limit, the verification information can be recognized and verified by the business backend. Once the time limit is exceeded, the verification information will be invalidated, and new user identity information needs to be provided and new verification information needs to be generated.

[0036] In addition, in this application, when the hybrid development APP is tested locally between the front-end and back-end, the business back-end provides a business interface for communication between the H5 webpage test front-end and the business back-end. The business interface is the interface provided by the business back-end to the H5 webpage test front-end for business communication. The business back-end and the H5 webpage test front-end perform business integration tests. The business back-end works in the background and controls the content of the H5 webpage test front-end. The H5 webpage test front-end faces the user, receives the user's input commands, and sends the received commands to the business back-end. After performing logic processing in the background, the business back-end returns data to the H5 webpage test front-end, which is then displayed on the H5 webpage test front-end.

[0037] When the H5 webpage testing frontend and the business backend communicate, the access request sent by the H5 webpage testing frontend to the business backend will carry a cookie containing verification information. This way, the business backend can obtain the verification information when it receives the access request, verify the verification information, and return the business data to the H5 webpage testing frontend after successful verification.

[0038] In some embodiments of this application, optionally, when an access request needs to communicate with multiple business backends, a plugin backend can be set up between the H5 webpage testing frontend and the business backend. The access request sent by the H5 webpage testing frontend to the business backend passes through the plugin backend, where the plugin backend retrieves the verification information from the cookie, translates it, and then provides it to the business backend. This improves the efficiency of joint debugging between the H5 webpage testing frontend and the business backend when the business communication volume is large.

[0039] Using the front-end and back-end communication method of H5 webpage in hybrid development APP proposed in this application, when the front-end and back-end are being integrated for local testing of hybrid development APP, a public plugin for introducing H5 webpage test front-end is used to embed the verification information generated by the server into the cookie of H5 webpage. When H5 webpage test front-end sends a request to the server, the server can directly read the verification information in the cookie and perform verification. When the verification is successful, business data is returned to H5 webpage test front-end.

[0040] In this way, when performing local integration testing of the front-end and back-end of a hybrid app, there's no need to rely on a test machine. Verification information can be directly obtained through the introduced public plugin and the testing interface provided by the plugin's backend. This verification information is then placed in the H5 webpage's cookie, enabling fast and efficient business communication between the front-end and back-end for H5 webpage testing. Furthermore, the account information used for integration testing can be switched at any time. As the account information changes, the verification information in the public plugin will automatically update. All of this is done in the background; integration testing personnel only need to switch accounts to perform business integration testing under different account information, thus significantly improving integration testing efficiency.

[0041] In the embodiments of this application, reference is made to Figure 3 After the joint debugging is completed, the following steps can be performed:

[0042] S201: After the joint debugging is completed, the client of the hybrid development APP sends a second request to the server to request verification information corresponding to the current user's identity information. The verification information is used to verify whether the business request sent by the front end of the H5 webpage to the server meets the user's identity information security requirements.

[0043] S202: In response to the second request, the server sends verification information to the client;

[0044] S203: The client stores the received verification information in the cookie of the H5 webpage;

[0045] S204: The front end of the H5 webpage sends an access request to the server, and the access request includes the H5 webpage's cookie;

[0046] S205: The server obtains the verification information from the cookie of the H5 webpage from the received access request, verifies the verification information, and allows loading the H5 webpage after successful verification.

[0047] In the embodiments of this application, after the joint debugging is completed, communication between the front-end and back-end of the H5 webpage will be carried out in the hybrid development APP. In this case, the client of the hybrid development APP sends a second request to the server, requesting to obtain verification information corresponding to the current user's identity information. In some embodiments, the current user's identity information may optionally be the username and password entered by the user when logging into the client of the hybrid development APP. After obtaining the username and password, the server responds to the second request and sends verification information to the client. The server responds to the second request and sends the verification information to the client. After obtaining the verification information, the client stores the verification information in the cookie of the H5 webpage. In this way, the cookie stores the verification information corresponding to the user's identity information. The front-end of the H5 webpage sends an access request to the server, which includes the cookie storing the verification information. The server obtains the verification information from the cookie, verifies the verification information, and opens the H5 webpage in the client after successful verification.

[0048] Using the front-end and back-end local integration method for H5 web pages in hybrid development APP proposed in this application, in the communication between the front-end and back-end of H5 web pages in hybrid development APP after integration, H5 web pages do not need to request verification information from the client first and then send the verification information to the server. Instead, the client directly stores the verification information in the cookie of H5 web pages. In this way, when H5 web pages send requests to the server, the server will directly obtain the verification information from the cookie and perform the verification. When the verification is successful, the loading of H5 web pages is allowed.

[0049] The method proposed in this application embodiment eliminates the need for the front-end and back-end of H5 web pages to focus excessively on verification information during communication. Instead, it allows them to concentrate more on business interactions between the front-end and back-end, thereby improving the efficiency of front-end and back-end communication and page loading.

[0050] In some embodiments of this application, the verification information may optionally include at least one of the following: user identity information, user login password, and verification code. During local front-end and back-end integration testing of a hybrid development app, the verification information is generated by the plugin back-end; after integration testing, the verification information is generated by the server corresponding to the client of the hybrid development app. Optionally, the verification information may be encoded user identity information generated by the plugin back-end or the server, or the user login password, or a verification code generated based on the user identity information. It should be noted that the form of verification information is diverse; any verification information used to verify identity during front-end and back-end communication is within the scope of protection of this application.

[0051] In some embodiments of this application, the verification information is optionally stored in a cookie as encrypted ciphertext. Encrypting the verification information improves information security and further enhances the information security of front-end and back-end communication in H5 web pages of hybrid development apps.

[0052] In some embodiments of this application, optionally, a gateway is set between the front end of the H5 webpage and the server; the server obtains verification information from the cookie and verifies the verification information, including: the front end of the H5 webpage sends the verification information to the server through the gateway; the server obtains the verification information and verifies the verification information.

[0053] After the integration is completed, access requests sent by the H5 webpage frontend are sent to the server through the gateway. The gateway first retrieves the verification information from the cookie, then translates the verification information and sends it to the server. After receiving the verification information, the server directly verifies the verification information, which can further improve the communication efficiency between the H5 webpage frontend and the server, as well as the loading efficiency of the H5 page.

[0054] The electronic device in this application embodiment may be a user terminal device, a server, other computing devices, or a cloud server. Figure 4 The diagram illustrates the hardware structure of an electronic device according to an embodiment of this application. The electronic device may include a processor 601 and a memory 602 storing computer program instructions. When the processor 601 executes the computer program instructions, it implements the process or function of any of the methods described above.

[0055] Specifically, processor 601 may include a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application. Memory 602 may include mass storage for data or instructions. For example, memory 602 may be at least one of the following: hard disk drive (HDD), read-only memory (ROM), random access memory (RAM), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, universal serial bus (USB) drive, or other physical / tangible memory storage device. Alternatively, memory 602 may include removable or non-removable (or fixed) media. Furthermore, memory 602 may be internal or external to the integrated gateway disaster recovery device. Memory 602 may be non-volatile solid-state memory. In other words, typically memory 602 includes a tangible (non-transitory) computer-readable storage medium (such as a memory device) encoded with computer-executable instructions, and when the software is executed (e.g., by one or more processors), it can perform the operations described in the methods of the embodiments of this application. The processor 601 implements the process or function of any of the methods described in the above embodiments by reading and executing computer program instructions stored in the memory 602.

[0056] In one example Figure 4The illustrated electronic device may also include a communication interface 603 and a bus 610. The processor 601, memory 602, and communication interface 603 are connected via bus 610 and communicate with each other. Communication interface 603 is primarily used to enable communication between modules, devices, units, and / or equipment in the embodiments of this application. Bus 610 may include hardware, software, or both, and can couple components of the online data traffic billing device together. For example, the bus may include at least one of the following: Accelerated Graphics Port (AGP) or other graphics bus, Enhanced Industry Standard Architecture (EISA) bus, Front Side Bus (FSB), HyperTransport (HT) Interconnect, Industry Standard Architecture (ISA) bus, Infinite Bandwidth Interconnect, Low Pin Count (LPC) bus, memory bus, Microchannel Architecture (MCA) bus, Peripheral Component Interconnect (PCI) bus, PCI-Express (PCI-X) bus, Serial Advanced Technology Attachment (SATA) bus, Video Electronics Standards Association Local (VLB) bus, or other suitable buses. Bus 610 may include one or more buses. Although specific buses are described or illustrated in the embodiments of this application, any suitable bus or interconnection method may be considered in the embodiments of this application.

[0057] In conjunction with the methods in the above embodiments, this application also provides a computer storage medium storing computer program instructions, which, when executed by a processor, implement the process or function of any of the methods in the above embodiments.

[0058] In addition, this application also provides a computer program product that stores computer program instructions, which, when executed by a processor, implement the process or function of any of the methods described above.

[0059] The flowcharts and / or block diagrams of methods, apparatuses, systems, and computer program products according to embodiments of this application have been exemplarily described above, and related aspects have been described. It should be understood that each block or combination thereof in the flowcharts and / or block diagrams may be implemented by computer program instructions, by dedicated hardware performing a specified function or action, or by a combination of dedicated hardware and computer instructions. For example, these computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to form a machine that enables the implementation of the function / action specified in each block or combination thereof in the flowcharts and / or block diagrams, executable via such processor. Such a processor may be a general-purpose processor, a dedicated processor, a special-purpose application processor, or a field-programmable logic circuit.

[0060] The functional blocks shown in the structural block diagrams of this application can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc.; when implemented in software, they are programs or code segments used to perform the required tasks. Programs or code segments can be stored in memory or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. Code segments can be downloaded via computer networks such as the Internet or intranets.

[0061] It should be noted that this application is not limited to the specific configurations and processes described above or shown in the figures. The above descriptions are merely specific embodiments of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the described systems, devices, modules, or units can be referred to the corresponding processes in the method embodiments, and need not be repeated here. It should be understood that the scope of protection of this application is not limited thereto. Any person skilled in the art can conceive of various equivalent modifications or substitutions within the scope of the technology disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application.

Claims

1. A method for local front-end and back-end integration testing of H5 web pages in hybrid APP development, applied in a development and testing environment, characterized in that... include: When performing local front-end and back-end integration testing for a hybrid development APP, the business back-end provides business interfaces to the H5 webpage test front-end of the hybrid development APP; A common plugin is introduced into the H5 webpage test frontend. The common plugin sends a first request to a plugin backend that is independent of the business backend through a test interface. The first request is used to request verification information corresponding to the user identity information used for joint debugging test. The first request includes at least one user identity information. The verification information is used to verify whether the business request sent by the H5 webpage test end to the server meets the user identity information security requirements during the local joint debugging process. In response to the first request, the plugin backend generates verification information and sends the verification information to the public plugin. The public plugin puts the verification information into the cookie of the H5 webpage. The verification information is time-sensitive. Within the time limit, the verification information can be recognized and verified by the business backend. If the time limit is exceeded, the verification information is invalidated, and new user identity information for joint debugging testing needs to be provided and new verification information is generated. The H5 webpage test frontend sends an access request to the business backend, and the access request carries the H5 webpage's cookie. The business backend retrieves the verification information from the H5 webpage's cookie from the received access request, verifies the verification information, and returns business data to the H5 webpage test frontend after successful verification, thus ending the integration test. When an access request needs to communicate with multiple business backends, the plugin backend is set up between the H5 webpage test frontend and the business backend. The access request sent from the H5 webpage test frontend to the business backend passes through the plugin backend, which retrieves the verification information from the cookie, translates it, and then provides it to the multiple business backends respectively.

2. The method according to claim 1, characterized in that, The method further includes: After the joint debugging is completed, the client of the hybrid development APP sends a second request to the server to request verification information corresponding to the current user's identity information. The verification information is used to verify whether the business request sent by the front end of the H5 webpage to the server meets the user's identity information security requirements. In response to the second request, the server sends verification information to the client; The client stores the received verification information in the cookie of the H5 webpage; The front end of an H5 webpage sends an access request to the server, and the access request includes the H5 webpage's cookie. The server retrieves the verification information from the cookie of the H5 webpage from the received access request, verifies the verification information, and allows the loading of the H5 webpage after successful verification.

3. The method according to claim 1 or 2, characterized in that, The verification information includes at least one of the following: user identity information, user login password, and verification code.

4. The method according to claim 1, characterized in that, The verification information is stored in a cookie as encrypted ciphertext.

5. The method according to claim 2, characterized in that, A gateway is set between the front end of the H5 webpage and the server; The server obtains the verification information from the cookie and verifies the verification information, including: The front end of the H5 webpage sends the verification information to the server through the gateway; The server obtains the verification information and verifies the verification information.

6. An electronic device, characterized in that, The electronic device includes a processor and a memory storing computer program instructions; when the electronic device executes the computer program instructions, it implements the method as described in any one of claims 1-5.

7. A computer-readable storage medium, characterized in that, The computer storage medium stores computer program instructions, which, when executed by a processor, implement the method as described in any one of claims 1-5.

8. A computer program product, characterized in that, It includes computer program instructions that, when executed by a processor, implement the method as described in any one of claims 1-5.

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