1 / 20

CSE 190: Internet E-Commerce

Learn about SOAP, a protocol for machine-to-machine communication using XML, that allows heterogeneous systems to interact and communicate securely using a firewall-friendly protocol. Explore how SOAP enables loose coupling, extensibility, and platform/language agnosticism.

kennethf
Download Presentation

CSE 190: Internet E-Commerce

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CSE 190: Internet E-Commerce Lecture 19: SOAP, WAP

  2. Machines that talk • We have web services for people • How do we enable machines that inter-operate? • XML as a way of representing data • But need a mechanism for communicating remote procedure calls. • Example: • Travel site providing driving directions to your hotel

  3. Motivations • Heterogeneous systems must be able to communicate • Binary protocols don’t always work • CORBA, DCOM, etc. don’t work well through firewalls • Nobody can agree on a standard binary format (usually due to platform-related issues) • We’re dealing with many heterogeneous environments (MVS, Unix, Windows NT, Linux, PalmOS, etc.) • Component runtimes differ • Security models differ (Kerberos, NTLM, OSF-DCE)

  4. What we need... • Standards (as usual) • A firewall-friendly protocol • An extensible framework • Low cost of entry • Loose coupling • Platform and programming language agnostic technology

  5. SOAP • SOAP: a method for doing RPC using XML to encode the parameters to our functions • For application to application integration • SOAP: Simple Object Access Protocol • Why not DCOM, CORBA, JNI? • Don’t natively work over HTTP, need custom ports • Even when they do, not human-readable • SOAP pitfall • Argument marshaling less efficient • A W3C Standard

  6. SOAP Example: Request <soap:Envelope> <soap:Body> <xmlns:m= "http://www.amzn.org/books" />    <m:GetBookPrice> <m:BookName>Fast Food Nation</m:BookName>       </m:GetBookPrice> </soap:Body> </soap:Envelope>

  7. SOAP Example: Response <soap:Envelope> <soap:Body> <xmlns:m="http://www.amzn.org/books" /> <m:GetBookPriceResponse> <m:Price>34.5</m:Price> </m:GetBookPriceResponse> </soap:Body> </soap:Envelope>

  8. SOAP Example: Error <soap:Fault> <faultcode>0x800700E</faultcode> <faulstring>Unknown book</faultstring> </soap:Fault>

  9. Envelope contains Header Body Header is optional Out-of-band information such as… Authentication information Message routes Logging Transaction flow Body contains XML body of RPC call SOAP Structure

  10. SOAP Example 2 <?xml version="1.0" encoding="UTF-8" ?> <env:Envelope xmlns:env="http://www.w3.org/2001/09/soap-envelope"> <env:Header> <n:alertcontrol xmlns:n="http://example.org/alertcontrol"> <n:priority>1</n:priority> <n:expires>2001-06-22T14:00:00-05:00</n:expires> </n:alertcontrol> </env:Header> <env:Body> <m:alert xmlns:m="http://example.org/alert"> <m:msg>Pick up Mary at school at 2pm</m:msg> </m:alert> </env:Body> </env:Envelope>

  11. Values and References • By value - Add([in] int a, [in] int b); • By reference - Square([in, out] int &a); <m:Add xmlns:m=“http://a.com/Calculator”> <a xsi:type=“integer”>3</a> <b xsi:type=“integer”>4</b> </m:Add> <m:Add xmlns:m=“http://a.com/Calculator”> <a href=“#arg” /> </m:Add> <a id=“arg” xsi:type=“integer”>8</a>

  12. Arrays • Arrays int a[3] = {1, 2, 3}; b = Add([in]a); <m:Add xmlns:m=“http://a.com/Calculator” xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/”> <a SOAP-ENC:arrayType=“xsd:int[3]”> <SOAP-ENC:int>1</SOAP-ENC:int> <SOAP-ENC:int>2</SOAP-ENC:int> <SOAP-ENC:int>3</SOAP-ENC:int> </a> </m:Add>

  13. SOAP over HTTP (Request) POST /Calculator.pl HTTP/1.0 Host: www.a.com Accept: text/* Content-type: text/xml Content-length: nnnn SOAPAction: “http://www.a.com/Calculator#Add” {CR}{LF} <SOAP-ENV:Envelope xmlns:SOAP-ENV=“http://schemas.xmlsoap.org/soap/envelope/” SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/”> <SOAP-ENV:Header> <t:transId xmlns:t=“http://a.com/trans”>1234</t:transId> </SOAP-ENV:Header> <SOAP-ENV:Body> <m:Add xmlns:m=“http://a.com/Calculator”> <a xsi:type=“integer”>3</a> <b xsi:type=“integer”>4</b> </m:Add> </SOAP-ENV:Body> </SOAP-ENV:Envelope>

  14. SOAP over HTTP (Response) HTTP/1.0 200 OK Content-type: text/xml Content-length: nnnn {CR}{LF} <SOAP-ENV:Envelope xmlns:SOAP-ENV=“http://schemas.xmlsoap.org/soap/envelope/” SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/”> <SOAP-ENV:Header> <t:transId xmlns:t=“http://a.com/trans”>1234</t:transId> </SOAP-ENV:Header> <SOAP-ENV:Body> <m:AddResponse xmlns:m=“http://a.com/Calculator”> <c xsi:type=“integer”>7</c> </m:AddResponse> </SOAP-ENV:Body> </SOAP-ENV:Envelope>

  15. WSDL(Web Services Description Language)Describing available SOAP Service(First, data types passed to web services) http://example.com/stockquote/stockquote.xsd <?xml version="1.0"?> <schema targetNamespace="http://example.com/stockquote/schemas" xmlns="http://www.w3.org/2000/10/XMLSchema"> <element name="TradePriceRequest"> <complexType> <all> <element name="tickerSymbol" type="string"/> </all> </complexType> </element> <element name="TradePrice"> <complexType> <all> <element name="price" type="float"/> </all> </complexType> </element> </schema>

  16. WSDL (cot’d)(Then, the actual methods and expected response structure) http://example.com/stockquote/stockquote.wsdl <?xml version="1.0"?> <definitions name="StockQuote" targetNamespace="http://example.com/stockquote/definitions" xmlns:tns="http://example.com/stockquote/definitions" xmlns:xsd1="http://example.com/stockquote/schemas" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns="http://schemas.xmlsoap.org/wsdl/"> <import namespace="http://example.com/stockquote/schemas" location="http://example.com/stockquote/stockquote.xsd"/> <message name="GetLastTradePriceInput"> <part name="body" element="xsd1:TradePriceRequest"/> </message> <message name="GetLastTradePriceOutput"> <part name="body" element="xsd1:TradePrice"/> </message> <portType name="StockQuotePortType"> <operation name="GetLastTradePrice"> <input message="tns:GetLastTradePriceInput"/> <output message="tns:GetLastTradePriceOutput"/> </operation> </portType> </definitions>

  17. SOAP + WSDL:Half of what .NET is about • .NET: Building web services as components that may be re-used in other applications • Hasn’t happened yet

  18. .NET (cot’d) • Second half of .NET: A set of language tools for developing web services and Win32 languages • New languages: C#, VB.NET • What’s new: Common Language Runtime • Allows multiple languages to use the same runtime libraries • Development tools: ASP.NET, ADO.NET • ASP.NET: Ignore the HTTP request/response structure and statelessness issues • Structure web sites as if you were assembling form code • ADO.NET: Disconnected record-sets (in memory DB)

  19. WAP, WML • WAP: Wireless Application Protocol • WML: Wireless Markup Language • Allows simple pages to be viewed by your mobile phone browser • Through a proxy, pages returned via normal HTTP • WML is not HTML • Standardized by the WAP forum

  20. WML Example • WML is an XML document <?xml version="1.0"?> <!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"> <wml> <card id="HTML" title="HTML Tutorial"> <p> Our HTML Tutorial is an award winning tutorial from W3Schools. </p> </card> <card id="XML" title="XML Tutorial"> <p> Our XML Tutorial is an award winning tutorial from W3Schools. </p> </card> </wml>

More Related