IT6801-SERVICE ORIENTED ARCHITECTURE

Transcription

1 ST.JOSEPH COLLEGE OF ENGINEERING DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING IT 6801-SERVICE ORIENTED ARCHITECTURE UNIT I 2 MARKS 1. Define XML. Extensible Markup Language(XML) is a markup language that define a set of rules for encoding documents in a format which is both human readable and machine readable. It is defined by the W3c s XML 1.0 specification and by several other related specifications all of which are free open standards. 2.Write the rules for XML declarations. If the XML declaration is included, it must contain version numbers attribute. The parameter names and attributes are case sensitive. The names are always in lower case. The order of placing the parameters is important. The correct order is version, encoding and standalone. 3.Define well-formed XML document A well formed documentation XML is a document that adheres to the syntax rules specified by the XML 1.0 specification in that it must satisfy both physical and logical structure requirements. 4.Define XML element. XML elements can be defined as the building blocks of an XML. Elements can behave as containers to hold text, elements, attributes, media objects or all of these. An element is an XML document is an object that begins with a start tag, may contain a value, and may terminate with an end tag. Syntax: <element-name attribute1 attribute 2>..content </element-name> 5.Define attributes. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 1

2 Attributes are part of the XML elements. An element can have multiple unique attributes. Attributes give more information about XML elements. Syntax: <element-name attribute1 attribute 2>..content </element-name> 6.Define DTD. The XML Document Type Declaration commonly knows as DTD is a way to describe XML language precisely. DTDs check vocabulary and validity of the structure of XML documents against grammatical rules of appropriate XML language. Syntax: <!DOCTYPE NOTE [ <!ELEMENT note(to, from, heading, body)> <! ELEMENT to(#pcdata)> <! ELEMENT from(#pcdata)> <! ELEMENT heading(#pcdata)> <! ELEMENT body(#pcdata)> ]> 7. What are the features of DTD. The elements that can appear in an XML document. The order in which they can appear. Optional and mandatory elements. Element attributes and whether are optional or mandatory. Whether attributes can have default values. 8.What are the types of DTD. The two types of DTD are Internal DTD and External DTD. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 2

3 When a DTD is declared within the file it is called Internal DTD and if it is declared in a separate file it is called External DTD. 9.What is a system identifier and public identifier. The system identifiers enables you to specify the location of an external file containing DTD declarations. Public identifiers provide a mechanism to locate DTD resources. 10.What is an empty rule in DTD. The element declarations does not contain any content. These are declared with the keyword EMPTY. Syntax: <!ELEMENT element name EMPTY> 11.What are the primary entities available in DTD. Built-in entities Character entities General entities Parameter entities 12.Define Valid XML document. A well formed XML document is considered as valid only if it contains a proper DTD and if the documents obey the constraints of that declarations. The constraints of the declarations will be expressed as a DTD or an XML schema. 13.Define Namespace. A name space is a set of unique names. Namespace is a mechanism by which element and attribute name can be assigned to a group. The namespace is identified by URI. Namespace use a colon delimited prefix to associate external semantics with elements. Example. <?xml version= 1.0?> <library xmlns= </library> [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 3

4 14.What is an XML schema? An XML schema is a document that describes the valid format for an XML data set. This definition include what elements are allowed at any point; what the attributes for any element may be; the number of occurrences of elements etc. 15. What are the advantages of schema over DTD. XML schema is a namespace aware while DTD is not. XML schema are written in XML, while DTD are not. XML schema is strongly typed, while DTD is not. XML schema does not allow inline definitions while DTD does. 16. What is an XPATH.? X-path address parts of an XML document. It provides a common syntax and semantics for functionality shared between XSL Transformations and X Pointer. It also provides basic facilities for manipulation of strings, numbers and Booleans. 17.What are the four object types in X-path? Node set Boolean Number String 18.Define predicates. Predicates are used to filter the nodes that are selected by the axes and node test. The predicate evaluated using Boolean operators. If the result is true, Then it defined that the node is present in the node set. Else it removed from the node set. 19.What is X Pointer? X pointer is same as X Path. But differs from X Path in the aspect as it describes a location on an external document. 20. Define X Link. X Link is used to create hyperlinks in XML documents. X Link provides a framework for creating both basic unidirectional links and more complex linking structures. 16 Marks 1.Explain the XML language structure in detail with suitable program. 2. Discuss in detail about well-formed and valid documents. 3.Ellaborate in detail about XML namespaces. 4.Write about the basic structure of DTD with suitable example. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 4

5 5. Discuss in brief about XML schema. 6.Write short notes on types of DTD. 7.Describe in detail about X path. 8.Briefly explain about X pointer. 9.Write short notes on X link. 2 MARKS 1.What is DOM? UNIT II DOMs are used to manipulate the contents of an XML document. XML documents when parsed, are represented as a hierarchical tree structure in memory. This tree structure contains the documents elements, attributes, contents etc. 2.What are the levels of DOM? Level 1: Used to traverse and manipulate XML document Level 2: Has the features of Level 1 and has some advanced features like namespace support, events, ranges, etc. 3.What are the advantages of DOM? Used to create and modify the XML document DOM is an object model for representing XML document XML DOM is language and platform independent XML DOM is traversable XML DOM is modifiable 4. List some of the nodes in DOM? Document node Element node Attribute node Text node CData node Processing instruction node 5.What are the different XSL elements? Stylesheet Valu-of For-each Sort Text [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 5

6 6. What is the use of SAX? SAX is an event drive SAX supports processing pipelines SAX requires programmers to maintain state. 7.State the Difference between DOM and SAX. S.No DOM SAX 1 Tree model parser(tree of nodes) Event based parser(sequence of events) 2 DOM loads the file into the memory and then parse the file. SAX parses the file at it reads. i.e. parses node by node 3 Has memory constraints since it loads the whole XML file before parsing No memory constraints as it does not store the XML content in the memory. 4 DOM is read and write SAX is read only 8.What are disadvantages of SAX? No random access to an XML document since it is processed in a forward only manner. To keep track of data the parser has been or change the order of items,you must write the code and store the data on your own. 9.What are the techniques available in XSLT processing? Client side-running in web browser. Which constitutes processor retrieving xml document and xsl stylesheet. Server side- This constitutes.net or JSP to transform xml document and send to client. 10.Define marshalling and unmarshalling Marshalling is to convert the java object into xml representation. Unmarshalling is the process of converting the xml back to java object. 11.What are all transformation techniques? XSLT XLINK XPATH 12.What is a schema compiler? Schema compiler binds a source to a set of schema derived program elements. The binding is described by an XML based binding language. 13.What are the advantages of XML database? Generating XSL-FO and display by XSL Formatter. It is self describing. It is portable and it can describe data in tree or graph structures. 14.What are the disadvantages of XML database? [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 6

7 It is verbose Access to the data is slow due to parsing and text conversion. 15.What are the steps for converting an XML to XSL-FO? Create a style sheet for concerned XML document Give XML document and XSL style sheet to the XSLT processor to produce XSL FO Get the output in any other forms like pdf. 16.Define XSLT Formatting XSL Formatting Objects is an XML based markup language which specifies in detail about pagination, layout, and styling information that will be applied to the content. 17.Define the scope of SAX Processing the XML document in a linear fashion from the top down The document is not deeply nested. Processing a very large XML document whose DOM tree would consume too much memory to represent one byte of XML. 18.What are the disadvantages of DOM. It consumes more memory as program written once remains in memory all the time until and unless removed explicitly. Due to the larger usage of memory its operational speed, compared to SAX is slower. 19.Define XSL-FO Block areas. XSL-FO Block areas defined small block elements like paragraphs tables and lists. It contains other block areas but most often they contain Line areas. 20.What are the components of page layout. Page Height Page Width Header Height Footer Height 16 MARKS 1.Write a program using DOM parser to calculate the average price of book. 2.Write an XSL file to display the book details in ascending order of price. 3.State the features of DOM. And explain about parsing an XML document using DOM in detail with suitable program. 4.How to do traversing in a DOM? 5. Explain in brief about parsing an XML document using SAX. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 7

8 6. How to validate an XML schema using SAX parser? 7.Describe briefly about XSLT. 8.Discuss in detail about XSLT processing on server side and client side. 9. How to model an XML database. 1. What is Service Oriented Architecture? UNIT-III 2 MARKS Service oriented architecture is essentially a collection of services. These services communicate with each other. The communication can involve either simple data passing or it could involve two or more services coordinating some activity. 2. Define Contemporary SOA. Contemporary SOA represents an architecture that promotes service orientation through the use of web services. 3. List out some characteristics of Contemporary SOA. Some of the characteristics of contemporary SOA are:- Contemporary SOA is at the core of the service oriented platform. Contemporary SOA increases quality of service. Contemporary SOA is fundamentally autonomous. Contemporary SOA is based on open standards. Contemporary SOA supports vendor diversity. Contemporary SOA fosters intrinsic interoperability. Contemporary SOA promotes discovery. Contemporary SOA promotes federation. Contemporary SOA promotes architectural composability. 4. What are the benefits of SOA? The benefits of SOA are: Improved integration and intrinsic interoperability Inherent reuse Streamlined architectures and solutions Leveraging the legacy investment Establishing standardized XML data representation Focused investment on communications infrastructure Best-of-breed alternatives Organizational agility 5. What are the common pitfalls of adopting SOA? [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 8

9 The common pitfalls of adopting SOA are: Building service oriented architectures like traditional distributed architectures Not standardizing SOA Not creating a transition plan Not starting with an XML foundation architecture Not understanding SOA performance requirements Not understanding web services security Not keeping in touch with product platforms and standards development 6. What are the requirements is needed to fill QoS gaps between contemporary and Primitive SOA? Contemporary SOA is striving to fill the QoS gaps of the primitive SOA model with the following requirements: Security (contents and access) Reliability (message guaranteed delivery) Appropriate performance Protecting business integrity Executing exception logic in case of failure 7.What is Architecture? Architecture refers a systematic arrangement of computerized automation technological solutions. 8. What is application architecture? Application architecture is a template for all others which specifically explained the technology, boundaries, rules, limitations, and design characteristics that apply to all solutions based on this template. 9. What is enterprise architecture? Enterprise architecture is a creation of master specification when numerous, disparate and integrate application architectures exist within an organization. 10. What is Single-tier client-server architecture? Single-tier client-server architecture is an environment in which bulky mainframe backends server served the thin clients. 11. List out the primary characteristics of the two tier client server architecture? The primary characteristics of the two tier client server architectures is given below which is compared to SOA i. Application logic ii. Application processing [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 9

10 iii. Technology iv. Security v. Administration 12. What is multi-tier client-server architectures? Multi-tier architecture (often referred to as n-tier architecture) is a client-server architecture in which the presentation, the application processing, and the data management are logically separate processes. 13. List out the types of communications of mainframe systems? The different types of communications of mainframe systems are: i. Synchronous communication ii. Asynchronous communication 14. Define synchronous communication. Synchronous communication allows the client and server to wait for each other to transfer the message. That is, the client will not continue until the server has received the message. 15. Define asynchronous communication. Asynchronous communication allows the server to continuously receive messages from the client without waiting for the server to respond. 16. List out the types of service autonomy? The different types of service autonomy are: i. Service-level autonomy ii. Pure autonomy 17. What are the key benefits of service reuse? The key benefits of service reuse are: i. Accommodate future requirements with less development effort ii. Reduce the need for creating wrapper services iii. Reduction of cost by not just avoiding duplication of code iv. Reducing risks by reusing well-tested code and runtime environments 18. What are the design characteristics required to facilitate interoperability in contemporary SOA? The design characteristics required to facilitate interoperability are: Standardization Scalability [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 10

11 Behavioral predictability Reliability 19. How is loose coupling concept achieved in SOA? The loose coupling concept is achieved by implementing standardized service abstraction layers when service orientation principles are applied to both business modeling and technical design. 20. What are the issues that are raised in the client-server and the distributed Internet architecture? The issues that are raised in the client-server and the distributed Internet architecture comparisons are discussed in a comparison between multi-tier client-server and SOA. Application logic Application processing Technology Security 16 MARKS 1.Discuss in detail about the characteristics of SOA. 2.Describe how SOA can be compared with client-server and distributed architectures. 3.Briefly explain about the principles of service orientation 5.What are the different service layers in SOA. Describe the layers in detail. 2MARKS 1.Define Web services UNIT IV A Web service (also Web Service, Web service) is defined by the W3C as a software system designed to support interoperable machine-to-machine.web Services is the umbrella term of group of loosely related Web-based resources and components that may be used by other Web. 2. List out the characteristic of Web services. XML based everywhere Message-based Programming language independent Could be dynamically located Could be dynamically assembled or aggregated Accessed over the internet Loosely coupled [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 11

12 3. What are the standard protocols used in web service? The standard protocols used in web service WSDL UDDL 4. Define WSDL WSDL stands for Web Services Description Language. WSDL is a document written in XML. The document describes a Web service. It specifies the location of the service and the operations (or methods) the service exposes. 5. Define UDDI Universal Description, Discovery and Integration (UDDI) is a platform-independent, XML- based registry for businesses worldwide to list themselves on the Internet. UDDI is an open industry initiative, sponsored by OASIS, enabling businesses to publish service listings and discover each other and define how the services or software applications interact over the Internet. 6. List out the UDDI register Public Register Private Register 7. What are the major elements used in WSDL? The major elements used in WSDL are Port Type Message Types Binding 8. Define WSDL Messages The element defines the data elements of an operation. Each message can consist of one or more parts. The parts can be compared to the parameters of a function call in a traditional programming language. 9. Define WSDL Type The element defines the data type that are used by the web service. For maximum platform neutrality, WSDL uses XML Schema syntax to define data types. 10. Define WSDL Binding The element defines the message format and protocol details for each port. 11. List the Web services platform elements: [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 12

13 SOAP (Simple Object Access Protocol) UDDI (Universal Description, Discovery and Integration) WSDL (Web Services Description Language) 12.Define Soap message. A SOAP message is specified as an XML Information Set. While all SOAP message examples in this document are shown using XML 1.0 syntax, other representations MAY be used to transmit SOAP messages between nodes. 13. Define Request-Response. Request-Response is a pattern in which the service consumer uses configured client software to issue an invocation request to a service provided by the service provider. The request results in an optional response. 14. Define Atomic Service Transaction Atomic Service Transaction is the name of a design pattern authored by Thomas Erl and published as part of the SOA Design Patterns catalog. Within the catalog this pattern is further categorized as one of the Composition Implementation Patterns. 15. List the Atomic Transaction Protocols A Completion protocol which is typically used to initiate the commit or abort states of the transaction. The Durable 2PC protocol for which services representing permanent data repositories should register. The Volatile 2PC protocol to be used by services managing non persistent (temporary) data. 16. Define Orchestration Refers to an executable business process that may interact with both internal and external Web services. Orchestration describes how Web services can interact at the message level, including the business logic and execution order of the interactions. These interactions may span applications and/or organizations, and result in a long-lived, transactional process. With orchestration, the process is always controlled from the perspective of one of the business parties. 17. Define Choreography More collaborative in nature, where each party involved in the process describes the part they play in the interaction. Choreography tracks the sequence of messages that may involve multiple parties and multiple sources. It is associated with the public message exchanges that occur between multiple Web services. 18. Define Orchestration service Orchestration services encapsulate the entire business process. For example, a service containing the entire flow of the Employer Registration" business process is an orchestration [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 13

14 service. The complete registration process identifying the employer type, determining liability and registering the employer in the database and various other steps. 19.Define Process/Orchestration-level Testing Process/Orchestration testing ensures services are operating collectively as specified. This phase of testing would cover business logic, sequencing, exception handling and process decomposition (including service and process reuse). 20. Define Composite Service Component A Composite Service Component is a component which combines the functionality of one or more other Foundational or Composite Service Components. It may also encapsulate additional functional and data enrichment, business process, etc. In some cases, a Composite Service Component may be purpose built to support one and only one business process or application, where it makes sense to encapsulate a piece of reusable functionality on the server side instead of in the application. 21. Define UDDI? SOA services are maintained in the enterprise by a registry that acts as a directory listing. Applications can look up the services in the registry and invoke the service. Universal Description, Definition, and Integration (UDDI) is the standard used for service registry. 16 MARKS: 1.Explain SOAP structure in detail with suitable example. 2.Describe briefly about manipulating WSDL. 3.Discuss in detail about service discovery and UDDI 4.Explain in detail about atomic transaction 5.Elaborate MEPs in detail. 6.Discuss about Orchestration and choreography in detail. 7.Explain service description with WSDL in detail. 2MARKS UNIT V 1.List out the stages to develop applications in WS-BPEL Denial - don't need it Coercion - management says we have to use it Elation - realization that it will solve all our enterprise application problems [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 14

15 Depression - realization that it will not solve all our enterprise application problems... yet Enlightenment - understanding how - and when - to leverage the advantages of SOA, via BPEL (in this case, using your Java skills as a guide) 2. Define the Reply activity. A Reply is responsible for extracting data from a process variable and placing it into a WSDL message that is then sent back in response to the one accepted by the preceding Receive. In fact syntactically, a Reply activity requires that the process have a Receive (or equivalent) somewhere earlier in the flow of the process. Here s the XML syntax our BPEL Process uses to reply to the loan approval 3. Define ACID Transaction ACID transactions They preserve the atomicity, consistency, isolation, and durability of the operation(s) encompassed by the transaction. This helps preserve the integrity of our programs logic execution as well as the integrity of the data managed by those programs. Java transaction managers are specifically designed to provide this functionality. 4. Define WS-Coordination framework The WS-Coordination framework exposes an Activation Service which supports the creation of coordinators for specific protocols and their associated contexts. The process of invoking an activation service is done asynchronously, and so the specification defines both the interface of the activation service itself, and that of the invoking service, so that the activation service can call back to deliver the results of the activation - namely a context that identifies the protocol type and coordinator location. 5. List the stages of WS-Coordination Instantiation (or activation) of a new coordinator for the specific coordination protocol, for a particular application instance Registration of participants with the coordinator, such that they will receive that coordinator's protocol messages during (some part of) the application's lifetime. Propagation of contextual information between Web services that comprise the application. An entity to drive the coordination protocol through to completion 6. Define WS-Coordination context A coordination identifier with guaranteed global uniqueness for an individual coordinator in the form of a URI An address of a registration service endpoint where parties receiving a context can register participants into the protocol A TTL value which indicates for how long the context should be considered valid Extensible protocol specific information particular to the actual coordination protocol supported by the coordinator 7.Define WS-Policy The Web Services Policy Framework (WS-Policy) provides a general purpose model and corresponding syntax to describe the policies of a Web Service. WS-Policy defines a base set of constructs that can be used and extended by other Web services specifications to describe a broad range of service requirements and capabilities. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 15

16 8.Define Composable Architecture The Web service specifications (WS*) are designed to be composed with each other to provide a rich set of tools for secure, reliable, and/or transacted Web services. WS-Policy by itself does not provide a negotiation solution for Web services. WS-Policy is a building block that is used in conjunction with other Web service and application specific protocols to accommodate a wide variety of policy exchange models. 9.Define fault handlers. Fault handlers are used to react to faults that occur while the business process activities are executing. The fault Handlers construct contain multiple catch element and a catch all child constructs. 10.What is catch element? The <catch> activity is used to specify faults that are to be caught and handled. At least one <catch> activity needs to be specified. 11.What is CatchAll element? The <catchall> activity is used to catch all faults. It is optional. 12.Give the overview of WS-Coordination. WS-Coordination is a framework for coordinating distributed activities Coordinator Activation service for creating coordination instance Registration service for registering participating application Additional protocol specific service Set of coordination protocols 13.What is the use of Coordination Context element? The Coordiantion Context is used to carry information about active coordination to participants Information inside context is coordination protocol specific Context format is not mandated by the standard Typically passed is SOAP headers 14.What are channels? Channels are the principle mechanism used to realize an interaction. A channel is named, described, and then related to the roles that realize its behavioral interface. A reference is provided to a service. The channel type will have the capability to derive its identity when in use. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 16

17 15.What is the goal of WS-Policy? WS-Policy provides the mechanisms needed to enable web services application to specify policies. 16.Give the specifications of WS-Policy framework. The WS-Policy framework is comprised of the following three specifications: WS-Policy WS-Policy Assertions WS-Policy Attachments 17.What is WS-Security? WS-Security is known as Web Services Security is a flexible extensible framework to SOAP to apply security to web services. 18.Why is WS-Security needed? The WS-Security is used to implement Message-level security measures Protect message contents during transport and during processing by service intermediaries. Authentication and authorization control Protect service provides from malicious requestors. 19.Give the syntax of WS-Security element. <Envelope> <Header>... <wsse:security actor=... mustunderstand=... >... </wsse:security> </Header> <Body>... </Body> </Envelope> [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 17

18 20.What is the use of the partner Link Type elements? The partner Link Type elements are used to identify the WSDL port Type elements referenced by the partner Link elements within the process definition. 16 MARKS 1.Elaborate briefly about Service Oriented Analysis. 2.Explain in detail about service oriented design in a step-by-step process. 3.Explain how Service Oriented Architecture is achieved in J2EE platform. 4. Explain briefly about WS-BPEL. 5.Discuss WS-Policy in detail. 6.Explain about SOA design standards. 7.Write short notes on SOA composition guidelines 8.Explain in detail about Service modeling in a step-by-step process. 9.Explain WS-Security in detail. [PREPARED BY G.S.JACKULIN ASHA/AP-CSE] Page 18