Dot Net Presentation 5

System.Net package  The System.Net namespace provides a simple programming interface for many of the protocols used on networks today classes      Various Cookie, CookieException Dns, DnsPermission HttpWebRequest, HttpWebResponse IPAddress, IPEndPoint, IPHostEntry  System.Net.Socket Classes      Socket TcpClient TcpListner UdpClinet Enumeration: ProtocolFamily,AddressFamily, ProtocolType. Web Services Overview Objectives  Background   Microsoft® .NET Framework Microsoft ASP.NET  Web Services    Overview Concepts and Architecture Design and Create Web Services Consume Web Services Contents  Section  Section  1: Overview 2: Architecture Microsoft .NET framework and ASP.NET  Section 3: Creating Web Services 4: Using Web Services 5: Advanced Web Services  Section  Invoking and consuming Web Services  Section  State Management, Security, and Transactions  Summary Section 1: Overview  “Looking  What are Back ...“ Web Services?  Distributed Web applications Looking Back ...  Traditional   distributed computing Client/server model Distributed object model    Components: packaging and interoperability Remoting: remote method invocation COM, CORBA, Java RMI and EJB  Microsoft   Windows DNA DNA (Distributed interNet Application) Architecture DHTML, COM, ASP, Message Queuing What’s Wrong with That?  Distributed  object models don„t scale to the Internet Tightly coupling service and consumer   Need for homogeneous infrastructure Versioning problems  Limited COM support on non-Windows platforms is a remoting architecture  CORBA   CORBA Component Model Server object implementation not portable Web Services—Basics  An  XML Web service is a programmable entity that provides a particular element of functionality, such as application logic, and is accessible to any number of potentially disparate systems  Expose  services to other processes Internet or intranet  Black  boxes Component-like, reusable  Based  on the .NET Framework on open standards ASP.NET Web Services model  Based  HTTP, XML, and SOAP  Interconnect    Web Services—Basics Applications Different clients (M)any device  Distribution and integration of application logic are loosely coupled  Web Services  Ubiquitous  Universal  Valuable  Communication Data Format contribution of XML Web services Fundamental piece of functionality for its clients to use [ Some algorithm ] To integrate a seemingly disparate group of existing applications [ Isolated island of data and business logic ]  Distributed Web Applications Devices, Browsers Access Application Call Services Vertical and portal service Application Internet App-specific Web Service Building block Web Service OS and local services Web Services Contract Section 2: Architecture  The .NET Framework Architecture  Programming Model  Configuration The .NET Framework Architecture Microsoft .NET Framework ASP.NET Web Forms Web Services Windows Forms Services Framework Base Data Debug ... Common Language Runtime System Services Programming model Source Code Compiler CIL & Metadata Common Language Runtime Execution Engine Class Loader Class Lib JIT Compiler Execution Managed native Code Configuration  Concepts   and architecture Web.Config file Hierarchical configuration architecture  Influence on the actual directory and all subdirectories Root Dir Sub Dir1 Web.Config Sub Dir2 Configuration  Web.Config file    XML based File is kept within the application directory Default and custom configuration  Customized Web.Config file  WebServicesConfiguration class   Contains configuration information section in Web.Config Section 3: Creating Web Services  Basics of Creating Web Services Infrastructure  Web Services  Code and Syntax Namespace  Web Services  Publishing  Discovery Creating Web Services—Basics  .asmx file   Virtual path of ASP.NET Web application Stand-alone or part of an existing solution  Web Services  infrastructure Discovery, description, and wire format  Directories – Central location to locate XML Web services UDDI (Universal Description, Discovery, and Integration) registry fulfill this role. - Process of locating, or discovering using the Web Services Description Language (WSDL). DISCO specification - an algorithm for locating service descriptions. - To understand how to interact with a particular XML Web service, provide a service description To enable universal communication, XML Web services communicate using open wire formats, which are protocols understandable by any system capable of supporting the most common Web standards.   Discovery  Description  Communicate - HTTP-GET and HTTP-POST or SOAP Web Services Infrastructure Request .vsdisco Discovery Return disco (XML) Request WSDL Web Service Client Description Return WSDL (XML) Web Service Request .asmx Protocol Return response (XML) Code and Syntax  WebService  Directive Settings for ASP.NET compilers <%@ WebService Language=value Class=value %>  WebMethod Attribute  Code  Declaration Syntax <%@ WebService Class=“MyClass.MyWebService“ %> Outline Inline (in C#) <%@ WebService Language=“C#“ Class=“MathService“ %> using System.Web.Services; public class MathService : WebService { [ WebMethod ] ...  Sample .asmx file <%@ WebService Language=“C#“ Class=“MathService“ %> using System; using System.Web.Services; public class MathService { [WebMethod] public int Subtract(int a, int b) { return a - b; } public int Subtract_vs(int a, int b) { return b - a; } } System.Web.Services Namespace 1/2  WebService   Base class for Web Services Provides base functionality  For example, WebService.Session  WebServiceAttribute  Optional class to add additional information [ WebMethod ]  WebMethodAttribute   Makes a method a Web Service method System.Web.Services Namespace 2/2  WebServiceBindingAttribute   Interface in WSDL Set of operations  WebServicesConfiguration   Contains configuration information section in config.web  WebServicesConfigurationSectionHandler Publishing a Web Service  Expose  Create    Web Service and Web Service methods a Web Service proxy and an assembly Generate proxy with WSDL tool Create an assembly Enables developers to program against Web Services  Publish WSDL contract and HTML description clients  Web Service  Can be Web applications or browsers Discovery of Web Services  .vsdisco file  XML-based file  containing links to resources for retrieving WSDL   Stored in the server„s root directory Access via URL and dynamic discovery document   Start discovering with the Disco tool Automatically created by Visual Studio.NET  Global  directory of Web Services through UDDI Universal Discovery, Description, and Integration (http://www.uddi.org) Disco.exe  Discovering Web Services example:  Command-line disco /out:location /domain:domain /username:username /password:password http://localhost/WebService1/ WebService1.vsdisco WSDL.exe  Web Services  Description Tool Create client proxy class  Input:   URL of a WSDL file, Proxy language, and protocol Username and password  Output:  Single source file in specified language, containing:   Proxy class Code for network invocation and marshalling wsdl /l:C# /protocol:protocol /out:filename /namespace:MathServiceSpace MathService.sdl Section 4: Using Web Services  Application  Invoking Model Web Services  Consuming Web Services Description Language (WSDL)  Web Services Application Model Web Service Developer Web Application Developer Web Server 1 asmx Service App .aspx Web Server 2 Proxy Web Form Service App Invoking Web Services  Web Services  are URL addressable HTTP request  Protocols  HTTP-GET  Method name and arguments in URL Method name and arguments in POST body  HTTP-POST   HTTP-SOAP  XML grammar for   Addressing the Web Service Returning results Invoking: HTTP-GET and HTTP-POST http://server/appl/service.asmx/method?param=value  Standard   HTTP-GET Method name = PATHINFO Method arguments = URL query string  Query string key = parameter name   Multiple parameters Only primitive .NET runtime data types  Result is an XML document  Any .NET data type  HTTP-POST  Similar to GET, but with arguments in the form body Invoking: HTTP-SOAP  XML  grammar for all standard .NET data types and value classes Web Service method, method parameters, results  Supports  Additionally: classes, structs, datasets  Class  and struct marshalling Serialization in XML format Consuming Web Services  Request   without method name and parameters HTML description of Web Service Service capabilities, methods, protocols  Web Service  can return WSDL HTTP-GET, HTTP-POST, and HTTP-SOAP  Request    with parameter “?WSDL” Formal WSDL description of Web Service XML-based grammar Can be used as input for WebServiceUtil.exe WSDL 1/2  XML   grammar, defining: Services and ports that communicate via messages Binding   Specify a protocol or a data format for a message or a port Extensions for SOAP 1.1, HTTP GET/POST, and MIME  Public  description of a Web Service and its content WSDL contract  Core   Elements of WSDL service, port, and portType operations and messages WSDL 2/2  An abstract illustration of WSDL elements service_1 port_C port_B service_2 message port_D port_A message port type Sample WSDL file

Section 5: Advanced Web Services  State Management  Security  Transactions  Execution Model Web Applications  Distributed State Management  Web Services  Use,  are stateless for example, ASP.NET session state Restricted to a logical application Context in which a user communicates to a server Request identification and classification Store data across multiple requests Session events Release of session data What is a session?    Functionality      .NET State Server Security Model  Reasons   for Security Prevent access to areas of your Web server Record and store secure relevant user data  Security Configuration Authorization, Impersonation ASP.NET App .NET  Authentication, Web Client IIS OS  Code  Access Security Walks the call stack to check authorization Transactions 1/2  Like ASP.NET Web Forms Services  COM+   COM+ automatic transactions Atomic, consistent, isolated, durable (ACID) SQL Server Application Web Service COM+ transaction context Message Queuing Server Transactions 2/2  TransactionOption Property on WebMethod Attribute: [WebMethod(TransactionOption= TransactionOption.Required)]  Transaction      Modes Disabled Supported NotSupported Required RequiresNew Execution Model  Synchronous  Like any other call to class methods  Asynchronous   .NET Framework design pattern Split the method into two code blocks   BeginMethodName EndMethodName  Client has to call Begin and End   Pass a callback function or WaitHandle class Using Web Services from UI  Completely  separate layout and processing logic .aspx .aspx.cs Two (or more) files: .aspx and .aspx.cs or .aspx.vb  Files  for designers and files for programmers Easy maintainability of your application Sample  .aspx <%@ Import Namespace=“MathServiceSpace“ %> ...   .asmx file implements method “Add” WSDL file, returned by the ASP.NET runtime Sample  C# proxy class, generated by WSDL.exe [System.Web.Services.Protocols. SoapDocumentMethodAttribute(“http://tempuri.org/Add“)] public int Add(int a, int b) { object[] results = this.Invoke(“Add“, new object[] {a, b}); return (int)(results[0]); } ... public System.IAsyncResult BeginAdd(... public int EndAdd(... Summary  .NET Architecture Overview and ASP.NET  Web Services  Create  Invoke and Publish Web Services and Consume Web Services Proxy Classes  WSDL and  Program Against Web Services Questions A Simple Web Service ASP.NET QuickStart Tutorial ASP.NET QuickStart  What Is   It? Tutorial, ASP.NET samples Syntax, architecture, features  Installation  Install Microsoft .NET Framework SDK  Visual Studio.NET installation and Components Update  Installation of Visual Studio.NET is not mandatory  .NET  Framework Samples ASP.NET QuickStart  ASP.NET Web Services  Writing a Simple Web Service Building a Simple Web Service  Create  your own MathService .asmx  Implement class MathService and Web methods Request to MathService.asmx WebServiceUtil.exe C# compiler “csc”  Create WSDL file (MathService.wsdl)   Generate C# proxy class (MathService.cs)   Generate Assembly (MathService.dll)  Consuming a Simple Web Service  Implement MathService  client (MathServiceClient.aspx) ASP.NET UI    Operands  Text box Methods  Buttons Result  Label OnServerClick  Event Handler  TerraServer. Microsoft.net Overview  What is   it? Set of Web methods Programmable interface to online database  Aerial imagery and topographical maps  Assumptions for   this tutorial Visual Studio.NET Internet connection Tutorial  Create  Create a new project application UI  Add Web reference  Implement functionality Legal Notices Unpublished work.  2001 Microsoft Corporation. All rights reserved. Microsoft, Visual Basic, Visual Studio, and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. The names of actual companies and products mentioned herein may be the trademarks of their respective owners.