The Web Service Portfolio Under Long Transaction Processing Research And Realization

With the rapid development of Web technology and E-commerce, Web services arise rapidly. Web services composition is composed of the existing Web services on the network, to provide more reliable, flexible, valuable service for network users.But in the composition of Web services, the reliability and consistency in the different Web services,and exception processing should be solved in time, therefore, the transaction function should be built in the Web services composition System.Transaction in the Web services composition usually has a long-cycle time and its structure is complicated ,which is quite different from tranditional transaction process. There are several web services composition models and descriptions but none provides the support of transaction process.Serveral sepecifications, such as WS-Coordination,WS-AT/WS-BA, have been promoted by IBM, Microsoft…etc. However, it is difficult to realize all the details in these specifications,and the web service composition feature is not yet considered.Although, BPEL provides the ability to define fault handling and compensation in an application–specific manner to support long-running business transaction,but still need to enhancement.A transaction process model based on Web service composition is proposed in the thesis,which can meet requirement on long-running transaction. The contributions are listed below:1 Analysing the problem of long-running transaction in the web service composition environment, reviewing the Web service transaction model and Web service transaction standard, introducing the key issues of Web service and Web service composition,anaylsing and extending the transaction process mechanism of BPEL .2 On the basis of the existing Web service transaction standards, a transaction process model is designed based on WS-C, and combining with the feature of Web service composition transaction as well as its design and implementation.Its work includes:solving the consistency problem through combining the compensation mechanism of WS-BA and BPEL;designing the transaction layer?the architecture of long-running transaction process,introducing composition of the architecture and coordination mechanism; illuminating the implementation of autonomous service's coordination support and application interface of business transaction. This transaction process model ,which has the character of cross-platform and easy to extend, can provide support for kinds of business process by building in the Web Services Archtitecture.3 The simulation experiment is carried on to confirm the transaction model, and an application based on the transaction model is introduced.4 The content of the thesis is summarized, the questions which should be improved in the further research are pointed out.