A QUERY BASED SYSTEM FOR OPTIMIZING WEB SERVICES

A QUERY BASED SYSTEM FOR OPTIMIZING WEB SERVICES THROUGH PROGRAM SLICING Ravindra Kumar Amit Kumar Balkaran Singh Sidhu Sudip Akura 01710403111 00710403111 05810403111 00210403111

Presentation Preview • • • Minor Project Work Problems to rectify Goals and Objective Abstract Theoretical Introduction Technical Introduction User Query Interface Design and Architecture Fallback Invocation Behavior Pending Work References

Minor Project Work • Topic- “Generation of Web Services through Program Slicing” – This project includes the development of an efficient tool based on Program Slicing technique in which a web service can be generated through choosing the slicing criteria based on methods. The main purpose is to generate Web Service with high optimization and performance factor

Problems to rectify • Address the problem of users and developers having to understand the operations in web services. • Reduce user interaction with web services • Map user queries to relevant operations in a domain specific web service • Faster execution of the web services.

Goals and Objectives • This project address the problem of users and developers having to understand the operations in web services and hide details of web service specification and implementation from users. • For efficient data retrieval and updating, fast service distribution and fault tolerance.

Abstract • This project abstract away the fundamental complexity of XML based Web services specifications and toolkits, and provide an elegant, intuitive, simple, and powerful query based invocation system to end users. We employ a set of algorithms and optimizations to match user queries with corresponding operations in Web services, invoke the operations with the correct set of parameters, and present the results to the end user. Our system uses the Semantic Web, Ontologies, Program Slicing and Caching in the process of automating Web services invocation and execution.

Introduction – Why this ? • Web services are rapidly emerging as a popular standard for sharing data and functionality among loosely-coupled, heterogeneous systems. • Many enterprises are moving towards a Service Oriented Architecture by putting their databases behind web services, thereby providing a well-documented, interoperable method of interacting with their data. • Furthermore, data not stored in traditional databases also is being made available via web services.

Introduction- Web Services • A web service is a network accessible interface for application functionality, built using standard Internet technologies. • Clients of web services do not need to know how it is implemented. Client Network Web Service Application Code

Introduction- Components of Web Services • WSDL (Web Service Description Language) – Describes three fundamental properties • What a service does, How a service is accessed, Where a service is located • SOAP (Simple Object Access Protocol) – A simple markup language for describing messages between applications • UDDI (Universal Description, Discovery and Integration) – A directory for storing information about web services

Introduction- Program Slicing • Program slicing is a technique for automatically decomposing programs by analysing their data flow and control flow. • In general a program slice consist of those statements that may directly or indirectly affect the variables computed at a given program point. – Depends on the program location – The criterion that defines the slicing problem is a pair C=(p, V) where p denotes program location – The criterion is the slicing criterion

Introduction- Program Slicing Example Function f(N) sum = 0; prod = 1; for(i = 0; i < N; ++i) { sum = sum + i; prod = prod *i; } write(sum); write(prod); Source Code Sliced Code<8, sum>

Introduction- Query Based System • Process user’s query and automatically determine which web services is to be used and which operation is to be performed. – What is the temperature in New Delhi? get. Current. Weather(3166) ID of City- NEW DELHI • Invoke the chosen operation by passing the input parameters and display the results • User does not have to fill detailed forms for each service

Introduction- Caching • A Cache is a component that stores data so future requests for that data can be served faster. • The data stored in a cache might be the results of an earlier computation, or the duplicates of data stored elsewhere. • A cache hit occurs when the requested data can be found in a cache, while a cache miss occurs when it cannot.

Introduction- Caching • ASP. NET provides three primary forms of caching: – Page level output caching • Keeps a copy of the HTML that was sent in response to a request in memory five attributes: – Supports User control level output caching (or fragment caching) Duration. Max 3600 seconds • Cached particular fragments Location- Client, Downstream, None, Server or Server. And. Client – Vary. By. Pram. Cache API none(no variation), “*”(all) • Store any serializeable data object, and control Vary. By. Headerbased on variation in specific headerhow that cache entry expires based on a combination one or more dependencies Vary. By. Custom variation e. g. . of. Browser • Example Cache. Insert("key", my. XMLFile. Data, new System. Web. Caching. Cache. Dependency(Server. Map. Path("users. xml")));

User Query Interface • • Accepts user query in a free from text box. Matches user’s query with web service descriptions. Invokes the relevant web service Displays results http: //localhost/My. Web. Services/Search. aspx Will there be rain tomorrow in New Delhi ? Output: Clear Cloud Max: 28 C Min: 20 C Search

Design & Architecture Weather. Info. asmx Will it be rain tomorrow at New Delhi? Output: Clear Cloud Max: 28 C Min: 20 C Methods: get. Weather. By. Loc() get. Weather. By. ID(loc. ID) get. Weather. By. ID(12)

Design & Architecture – Query Based System

Design & Architecture – Program Slicing Login() Compose() Inbox() Sent_Mail()

Design & Architecture – Invocation and Caching http: //localhost/My. Web. Services/Class. Name. asmx SOAP Envelope after passing parameters: string _soap. Envelope = <soap: Envelope xmlns: xsi="http: //www. w 3. org/2001/XMLSchema-instance" Empty SOAP Envelope: xmlns: xsd="http: //www. w 3. org/2001/XMLSchema" string _soap. Envelope = <%@ Web. Service language ="C#" class = “Class. Name" %> xmlns: soap="http: //schemas. xmlsoap. org/soap/envelope/"> @"<soap: Envelope <soap: Body> xmlns: xsi='http: //www. w 3. org/2001/XMLSchema-instance' <login. Mail xmlns="http: //localhost/My. Web. Services/"> xmlns: xsd='http: //www. w 3. org/2001/XMLSchema' <user. ID>ravin@gmail. com</user. ID> xmlns: soap='http: //schemas. xmlsoap. org/soap/envelope/'> <Pwd>Password@123</Pwd> <soap: Body></soap: Envelope>"; Wait for 3 Sec(Time Window) <port. Addrs>993</port. Addrs> Fetch all request, Send single request <host. Addrs>imap. gmail. com</host. Addrs> </login. Mail> request. Get. Response() </soap: Body> </soap: Envelope>

Fallback Invocation Behavior • If no operation can be identified after matching query with Web files • User is presented with a form with links to various operations. • User can select the desired operation • Information pre-filled in the form based on user query • If nothing works user asked to refine query.

Pending Work • Saving and checking output in cache • Match Processor and WS Invoker in Query based system Caching Module (Invocation & Caching) Includes- Cache check and storing result Includes- Invocation of WS when QBS detect it WS Invoker (Query based system)

References [1] Chaitali Gupta, Rajdeep Bhowmik, Michael R. Head, Madhusudhan Govindaraju and Weiyi Meng , “A Querybased System for Automatic Invocation of Web Services”. [2] Yingzhou Zhang , Wei Fu, Geng Yang, Lei Chen and Weifeng Zhang, “Web Service Generation Through Program Slicing” , Int. J. Communications, Network and System Sciences, 2010, 3, 877 -887. [3] Julio Fernandez Vilas, Ana Fernandez Vilas and Jose Pazos Arias, “Optimizing Web Services Performance using Cache”, International Conference on Next Generation Web Services Practices, 2005