The Mythical XML

The Mythical XMLThe Mythical XML

Mr. Thomas LeeMr. Thomas LeeCenter for ECenter for E--Commerce Infrastructure Development Commerce Infrastructure Development (CECID), The University of Hong Kong(CECID), The University of Hong Kong

HK Computer Society XML Specialist Group HK Computer Society XML Specialist Group SpeakerSpeaker’’s Sessions Session26 August 2003, HK Polytechnic University26 August 2003, HK Polytechnic University

26 August 200326 August 2003 HKCS XMLSG Speaker's Meeting HKCS XMLSG Speaker's Meeting -- Mythical XMLMythical XML 22

AgendaAgenda

XML BasisXML BasisWeb ServicesWeb ServicesXML Development in HKXML Development in HKDemoDemo

XML BasisXML Basis


True or False?True or False?

XML = Extensible Markup LanguageXML = Extensible Markup LanguageXML is an extension of HTMLXML is an extension of HTML–– XML is going to replace HTML for Web XML is going to replace HTML for Web

browsingbrowsing

Tags are not predefined in XMLTags are not predefined in XML–– You must You must define your own tagsdefine your own tags

XML specifies data semanticsXML specifies data semantics


Background of XMLBackground of XML

eeXXtensible tensible MMarkup arkup LLanguageanguageXML 1.0 became a W3C Recommendation in XML 1.0 became a W3C Recommendation in 19981998F.O.XF.O.X (Father of XML) (Father of XML) -- Jon Jon BosakBosak–– a SUN architect, who led a group to create XMLa SUN architect, who led a group to create XML

Over 20 XMLOver 20 XML--related specs at W3C in 2003related specs at W3C in 2003Over 200 XML application standards for Over 200 XML application standards for different industries registered at XML.orgdifferent industries registered at XML.org–– Finance, healthcare, eFinance, healthcare, e--government, mathematic, government, mathematic,

telecomtelecom……


A A markupmarkup languagelanguage for documents containing for documents containing structured structured informationinformation

–– i.e. a data format for structurally delimiting text data with i.e. a data format for structurally delimiting text data with tagstags

For For computercomputer--toto--computer communicationcomputer communication

XML is not going to replace HTMLXML is not going to replace HTML

HTMLHTMLEncode content and Encode content and presentationpresentationTags are already defined for Tags are already defined for rendering the content on rendering the content on browsers (one application only)browsers (one application only)Semantics has already been Semantics has already been defined in HTML specdefined in HTML spec

XMLXMLEncode structure + content Encode structure + content (no presentation)(no presentation)Tags are to be defined by Tags are to be defined by different applications for different applications for processing the contentprocessing the contentSemantics is not defined in Semantics is not defined in XML specXML spec

What is XML?What is XML?


Weather Weather Forecast Forecast in in BrowserBrowser


Weather Forecast Weather Forecast in HTMLin HTML


Weather Forecast in XMLWeather Forecast in XML

1.1. <?xml version="1.0"?><?xml version="1.0"?>2.2. <<WeatherForecastWeatherForecast>>3.3. <<CityCity namename="="Hong KongHong Kong">">4.4. <<WeatherWeather datedate="="20032003--0808--2626">">Light RainLight Rain</</WeatherWeather>>5.5. <<WeatherWeather datedate="="20032003--0808--2727">">ShowersShowers</</WeatherWeather>>6.6. </</CityCity>>7.7. <<CityCity namename="="BeijingBeijing">">8.8. <<WeatherWeather datedate="="20032003--0808--2626">">CloudyCloudy</</WeatherWeather>>9.9. <<WeatherWeather datedate="="20032003--0808--2727">">Thunder ShowerThunder Shower</</WeatherWeather>>10.10. </</CityCity>>11.11. </</WeatherForecastWeatherForecast>>

Start Tag

Element

End Tag

Attribute

Data Value


XML Document StructureXML Document Structure

WeatherForecast

City:name=“Hong Kong”

Weather:date=“2003-08-26”

City:name=“Beijing”




Light Rain Showers Cloudy Thunder Showers


XSLTXSLT

XMLXML StylesheetStylesheet Language TransformationLanguage Transformation

A scripting language to transform a XML document A scripting language to transform a XML document to different document formsto different document forms–– another XML form, HTML, text, etc.another XML form, HTML, text, etc.

Can present XML data in different rendering Can present XML data in different rendering languages, e.g. HTML, WMLlanguages, e.g. HTML, WML–– separation of content and presentationseparation of content and presentation

Can translate to a different XML form (conforming Can translate to a different XML form (conforming to a different XML schema)to a different XML schema)–– interoperabilityinteroperability between different applications, e.g. between different applications, e.g.

vendor productsvendor products


XSLT ExampleXSLT Example<?xml version="1.0" encoding="UTF<?xml version="1.0" encoding="UTF--8"?>8"?><<xslxsl::stylesheetstylesheet versionversion="="1.01.0""

xmlnsxmlns::xslxsl="="http://www.w3.org/1999/XSL/Transformhttp://www.w3.org/1999/XSL/Transform">"><<xslxsl:output:output methodmethod="="htmlhtml"" versionversion="="1.01.0"" encodingencoding="="UTFUTF--88"" indentindent="="yesyes"/>"/><<xslxsl:template:template matchmatch="="//">">

<<htmlhtml>><<headhead>>

<<titletitle>>Weather ForecastWeather Forecast</</titletitle>></</headhead>><<bodybody>>

<<h1h1>>Weather ForecastWeather Forecast</</h1h1>><<xslxsl:apply:apply--templatestemplates/>/>

</</bodybody>></</htmlhtml>>

</</xslxsl:template:template>>


XSLT Example (2)XSLT Example (2)<<xslxsl:template:template matchmatch="="CityCity">">

<<h2h2>><<xslxsl:apply:apply--templatestemplates selectselect="="@name@name"/>"/>

</</h2h2>><<tabletable borderborder="="11">">

<<tbodytbody>><<trtr>>

<<thth>>DateDate</</thth>><<thth>>WeatherWeather</</thth>>

</</trtr>><<xslxsl:apply:apply--templatestemplates/>/>

</</tbodytbody>></</tabletable>>

</</xslxsl:template:template>>


XSLT Example (3)XSLT Example (3)

<<xslxsl:template:template matchmatch="="WeatherWeather">"><<trtr>>

<<tdtd>><<xslxsl:apply:apply--templatestemplates selectselect="="@date@date"/>"/>

</</tdtd>><<tdtd>>

<<xslxsl:apply:apply--templatestemplates selectselect="="text()text()"/>"/></</tdtd>>

</</trtr>></</xslxsl:template:template>>

</</xslxsl::stylesheetstylesheet>>


Schema LanguageSchema Language

A schema language is used to A schema language is used to validatevalidate the XML data whether the XML data whether it is in valid form for a specific applicationit is in valid form for a specific application–– the tag setthe tag set–– the structure in which the tags can be placedthe structure in which the tags can be placed–– the format of the values markedthe format of the values marked--up by tags and attributes valuesup by tags and attributes values

Data Type Definition (DTD) and Data Type Definition (DTD) and W3C XML SchemaW3C XML SchemaTo define an To define an XML application standardXML application standard–– e.g. XBRL (XML Business Reporting Language)e.g. XBRL (XML Business Reporting Language)

Not sufficient define semanticsNot sufficient define semantics–– semantics is defined in a supplementary vocabulary or semantics is defined in a supplementary vocabulary or

specificationspecificationNot designed to program application logicNot designed to program application logic–– e.g. cannot convert temperature between degrees Celsius and e.g. cannot convert temperature between degrees Celsius and

FahrenheitFahrenheit


XML Schema ExampleXML Schema Example<?xml version="1.0" encoding="UTF<?xml version="1.0" encoding="UTF--8"?>8"?><<xsxs:schema:schema xmlnsxmlns::xsxs="="http://www.w3.org/2001/http://www.w3.org/2001/XMLSchemaXMLSchema">">

<<xsxs:element:element namename="="WeatherForecastWeatherForecast">"><<xsxs::complexTypecomplexType>>

<<xsxs:sequence:sequence>><<xsxs:element:element namename="="CityCity"" minOccursminOccurs="="00"" maxOccursmaxOccurs="="unboundedunbounded">">

<<xsxs::complexTypecomplexType>><<xsxs:sequence:sequence>>

<<xsxs:element:element namename="="WeatherWeather"" minOccursminOccurs="="00"" maxOccursmaxOccurs="="unboundedunbounded">"><<xsxs::complexTypecomplexType>>

<<xsxs::simpleContentsimpleContent>><<xsxs:extension:extension basebase="="xsxs:string:string">">

<<xsxs:attribute:attribute namename="="datedate"" typetype="="xsxs:date:date"" useuse="="requiredrequired"/>"/></</xsxs:extension:extension>>

</</xsxs::simpleContentsimpleContent>></</xsxs::complexTypecomplexType>>

</</xsxs:element:element>></</xsxs:sequence:sequence>><<xsxs:attribute:attribute namename="="namename"" typetype="="xsxs:string:string"" useuse="="requiredrequired"/>"/>

</</xsxs::complexTypecomplexType>></</xsxs:element:element>>

</</xsxs:sequence:sequence>></</xsxs::complexTypecomplexType>>

</</xsxs:element:element>></</xsxs:schema:schema>>


True or False (Answers)True or False (Answers)

XML = Extensible Markup LanguageXML = Extensible Markup LanguageXML is an extension of HTMLXML is an extension of HTML–– XML is going to replace HTML for Web XML is going to replace HTML for Web

browsingbrowsing

Tags are not predefined in XMLTags are not predefined in XML–– You must You must define your own tagsdefine your own tags

XML specifies data semanticsXML specifies data semantics

Web ServicesWeb Services


Weather Info EverywhereWeather Info Everywhere


How to Automatically Obtain How to Automatically Obtain Weather Info from HKO?Weather Info from HKO?

Now:Now:–– poll HKO web pagespoll HKO web pages–– ““trytry”” to decodeto decode the text contained within the text contained within

(based on the current web page layout)(based on the current web page layout)–– 300+300+ have registered web sites, mass media, have registered web sites, mass media,

telecom operators using this methodtelecom operators using this method–– problem: a slight change to layout or data problem: a slight change to layout or data

format would cause problems to these usersformat would cause problems to these users

Better solution:Better solution:–– Use Web ServicesUse Web Services


What is Web Service?What is Web Service?

Remote procedure callRemote procedure call (distributed (distributed computing) on the Internet using XMLcomputing) on the Internet using XMLExposes Exposes functionality through a standard functionality through a standard protocolprotocolDescribes Describes the interfaces in enough detail the interfaces in enough detail to for building client applications to talk to to for building client applications to talk to themthemRegisters Registers the services so that potential the services so that potential users can find them easilyusers can find them easily


SOAPSOAP

Simple Object Access ProtocolSimple Object Access ProtocolUses XML to package input and output data on Uses XML to package input and output data on making a remote procedure call (RPC) on the making a remote procedure call (RPC) on the InternetInternetUses Internet protocols for data transport, e.g. Uses Internet protocols for data transport, e.g. HTTP, SMTPHTTP, SMTP–– Firewall friendlyFirewall friendly

Platform independentPlatform independent–– .Net and Java programs can talk with each other in SOAP.Net and Java programs can talk with each other in SOAP

http://www.w3c.orghttp://www.w3c.org

http://www.w3c.org/

http://www.w3c.org/


SOAP RequestSOAP RequestPOST /POST /weatherwarningweatherwarning/services//services/WeatherWarningWeatherWarning HTTP/1.0HTTP/1.0ContentContent--Type: text/xml;Type: text/xml; charsetcharset==utfutf--88Accept: application/soap+xml, application/dime, multipart/relateAccept: application/soap+xml, application/dime, multipart/related, text/*d, text/*UserUser--Agent: Axis/1.1RC2Agent: Axis/1.1RC2Host: 127.0.0.1Host: 127.0.0.1CacheCache--Control: noControl: no--cachecachePragmaPragma: no: no--cachecacheSOAPActionSOAPAction: "": ""ContentContent--Length: ###Length: ###

<?xml version="1.0" encoding="UTF<?xml version="1.0" encoding="UTF--8"?>8"?><<soapenvsoapenv:Envelope:Envelope

xmlnsxmlns::soapenvsoapenv="http://schemas.="http://schemas.xmlsoapxmlsoap.org/soap/envelope/".org/soap/envelope/"xmlnsxmlns::xsdxsd="http://www.w3.org/2001/="http://www.w3.org/2001/XMLSchemaXMLSchema""xmlnsxmlns::xsixsi="http://www.w3.org/2001/="http://www.w3.org/2001/XMLSchemaXMLSchema--instance">instance">

<<soapenvsoapenv:Body>:Body><ns1:<ns1:getWarning getWarning

soapenvsoapenv::encodingStyleencodingStyle="http://schemas.="http://schemas.xmlsoapxmlsoap.org/soap/encoding/".org/soap/encoding/"xmlnsxmlns:ns1="http://model.:ns1="http://model.weatherwarningweatherwarning..webservicewebservice..hkohko..cecidcecid..hkuhku..hkhk"/>"/>

<ns1:type>typhoon</ns1:type><ns1:type>typhoon</ns1:type></ns1:</ns1:getWarninggetWarning>>

</</soapenvsoapenv:Body>:Body></</soapenvsoapenv:Envelope>:Envelope>


SOAP ResponseSOAP ResponseHTTP/1.1 200 OKHTTP/1.1 200 OKContentContent--Type: text/xml;Type: text/xml; charsetcharset==utfutf--88Date: Tue, 26 Aug 2003 02:25:37 GMTDate: Tue, 26 Aug 2003 02:25:37 GMTServer: Apache Coyote/1.0Server: Apache Coyote/1.0Connection: closeConnection: close

<?xml version="1.0" encoding="UTF<?xml version="1.0" encoding="UTF--8"?>8"?><<soapenvsoapenv:Envelope:Envelope

xmlnsxmlns::soapenvsoapenv="http://schemas.="http://schemas.xmlsoapxmlsoap.org/soap/envelope/".org/soap/envelope/"xmlnsxmlns::xsdxsd="http://www.w3.org/2001/="http://www.w3.org/2001/XMLSchemaXMLSchema""xmlnsxmlns::xsixsi="http://www.w3.org/2001/="http://www.w3.org/2001/XMLSchemaXMLSchema--instance">instance">

<<soapenvsoapenv:Body>:Body><ns1:<ns1:getWarningResponse getWarningResponse

soapenvsoapenv::encodingStyleencodingStyle="http://schemas.="http://schemas.xmlsoapxmlsoap.org/soap/encoding/".org/soap/encoding/"xmlnsxmlns:ns1="http://model.:ns1="http://model.weatherwarningweatherwarning..webservicewebservice..hkohko..cecidcecid..hkuhku..hkhk">"><return <return xsixsi:type=":type="xsdxsd:string">:string">強烈季候風信號強烈季候風信號</return></return>

</ns1:</ns1:getWarningResponsegetWarningResponse>></</soapenvsoapenv:Body>:Body></</soapenvsoapenv:Envelope>:Envelope>


WSDLWSDL

Web Services Description LanguageWeb Services Description LanguageSpecifies the data types and structures (in XML Specifies the data types and structures (in XML Schema) of input and output data for a SOAP callSchema) of input and output data for a SOAP callSpecifies other transport parameters, e.g. protocol, Specifies other transport parameters, e.g. protocol, URL endURL end--point, etc.point, etc.Tells the clients how to make a SOAP call to use a Tells the clients how to make a SOAP call to use a specific Web Servicespecific Web Service–– similar to Interface definition language (IDL) for RPCsimilar to Interface definition language (IDL) for RPC

http://www.w3c.orghttp://www.w3c.org

http://www.w3c.org/

http://www.w3c.org/


UDDIUDDI

Universal Description, Discovery and IntegrationUniversal Description, Discovery and IntegrationA registry to register, publish, find Web ServicesA registry to register, publish, find Web Services–– white pages, or basic identification: name, address, and white pages, or basic identification: name, address, and

key points of contactkey points of contact–– yellow pages, or classification by a standard index of yellow pages, or classification by a standard index of

business and industriesbusiness and industries–– green pages, or technical capabilities and services related green pages, or technical capabilities and services related

to the conduct of electronic businessto the conduct of electronic business

Similar to a portal for system clientsSimilar to a portal for system clientshttp://www.http://www.uddiuddi.org.org

http://www.uddi.org/

http://www.uddi.org/


ebXMLebXML

EE--business XMLbusiness XMLCoCo--developed by developed by UN/CEFACTUN/CEFACT and and OASISOASISXMLXML--based document exchangebased document exchange architecture to architecture to perform Electronic Data Interchange (EDI) on the perform Electronic Data Interchange (EDI) on the InternetInternetProvides Provides reliable and securereliable and secure document exchange document exchange on the Interneton the InternetSupports Supports business process specificationbusiness process specification for for system executionsystem executionWidely adopted in Asia and EuropeWidely adopted in Asia and Europe–– HK is an ebXML forerunnerHK is an ebXML forerunner

XML Development in HKXML Development in HK


eProcurement eProcurement CaseCase

MTRCMTRC purchases office supplies from purchases office supplies from SaggioSaggio on on SaggioDirectSaggioDirect.com.comPast: plentiful of delivery notes, invoices, monthly Past: plentiful of delivery notes, invoices, monthly statements were sent in paper and reconciled statements were sent in paper and reconciled manuallymanuallyPresent: XML documents are transferred on the Present: XML documents are transferred on the Internet using Internet using ebXMLebXML–– automatic reconciliationautomatic reconciliation–– save costs and treessave costs and trees–– procurement data ready for analysis and planningprocurement data ready for analysis and planning


eProcurementeProcurement with ebXMLwith ebXML

SaggioDirect System

Web Server

Hermes

Workstations

MTRC Intranet System

MTRC Users

XML document

Internet

Extract datafrom XML document

XML document

Saggio Logistics Delivery goods

Hermes

IntranetServer


eLogistics eLogistics CaseCase

Shipping companies electronically submit Shipping companies electronically submit dangerous goods manifestsdangerous goods manifests to Marine to Marine Department using ebXMLDepartment using ebXMLParticipating pilot shipping companies: Participating pilot shipping companies: OOCLOOCL andand APLAPLPilot production in July 2003Pilot production in July 2003Saved data reentry required by WebSaved data reentry required by WebWill cover other port formality documents, e.g. preWill cover other port formality documents, e.g. pre--arrival notification, general declarationarrival notification, general declaration……Issue: need to design Issue: need to design XML SchemasXML Schemas for various for various port formality documentsport formality documents


Dangerous Goods Declaration with ebXMLDangerous Goods Declaration with ebXMLShippingAgentsShippingAgents

Marine Dept

Paper submission

Web submissionInternet

XML submissionebXML Message Service

over HTTP on VPN

HermesMSH

HermesMSH

1

2

3


XML Schema Design and XML Schema Design and Management GuideManagement Guide

For HKSARG to implement eFor HKSARG to implement e--government joinedgovernment joined--up servicesup services–– enhance enhance data interoperabilitydata interoperability

Systematic modelling methodology for designing Systematic modelling methodology for designing reusable reusable XML SchemasXML Schemas–– facilitates design of consistent, quality and reusable schemasfacilitates design of consistent, quality and reusable schemas–– consolidated international best practices, e.g. CCTS, UBLconsolidated international best practices, e.g. CCTS, UBL

Flexible management framework for standardizing Flexible management framework for standardizing Common Common SchemasSchemas, e.g. HKID Number, Person Name, Postal Address, e.g. HKID Number, Person Name, Postal Address–– minimizes repetitive data alignment efforts by standardizing minimizes repetitive data alignment efforts by standardizing

schemas for commonly used data elementsschemas for commonly used data elementsUnder public consultationUnder public consultation–– http://www.http://www.itsditsd..govgov..hkhk//itsditsd//englishenglish/infra//infra/eifeif..htm htm

Pilot project: Pilot project: HK Observatory plans to broadcast weather HK Observatory plans to broadcast weather information in XML through Web Services/HTTPinformation in XML through Web Services/HTTP

http://www.itsd.gov.hk/itsd/english/infra/eif.htm


Weather Information in XML/WSWeather Information in XML/WS


Digital Trade and Digital Trade and Transportation NetworkTransportation Network

A neutral, highA neutral, high--tech, and valuetech, and value--added eadded e--logistics logistics platformplatform–– facilitate information flow & service integrationfacilitate information flow & service integration–– pearl River Delta (PRD), regionally & globallypearl River Delta (PRD), regionally & globally–– based on openbased on open--standards, e.g. XML / ebXMLstandards, e.g. XML / ebXML–– SME is an important focusSME is an important focus–– releases 1 and 2 completed in 12releases 1 and 2 completed in 12--15 months15 months

Return on investmentReturn on investment–– estimated investment: HK$3B over 17 yearsestimated investment: HK$3B over 17 years–– estimated benefit: HK$11B over 17 yearsestimated benefit: HK$11B over 17 years

http://www.http://www.logisticshklogisticshk..govgov..hkhk

http://www.logisticshk.gov.hk/

http://www.logisticshk.gov.hk/


Proposed DTTN ArchitectureProposed DTTN Architecture


OpenOpen--Source Software Source Software (OSS) Development(OSS) Development

Conditions to advance global eConditions to advance global e--commerce developmentcommerce development–– high interoperability and reliability, low costhigh interoperability and reliability, low cost–– therefore, open standards and opentherefore, open standards and open--source softwaresource software

HK is the world champion in ebXML OSSHK is the world champion in ebXML OSSFreebXMLFreebXML.org.org to promote the development and adoption of to promote the development and adoption of openopen--source technologies for esource technologies for e--commercecommerce–– international collaboration: HKU (HK), Cyclone (US), ECOM international collaboration: HKU (HK), Cyclone (US), ECOM

(Japan), (Japan), KasetartKasetart U. (Thailand), KIEC (Korea), U. (Thailand), KIEC (Korea), SigmaLogicaSigmaLogica (US), (US), Sterling Commerce (US), Sun (US), Sybase (US)Sterling Commerce (US), Sun (US), Sybase (US)

Our vision: Our vision: FreebXMLFreebXML –– the the ““LinuxLinux”” and and ““ApacheApache”” in the ein the e--commerce developmentcommerce development



Global Penetration of Global Penetration of MadeMade--inin--HK OSSHK OSS

Many serious users in Asia and Europe!Many serious users in Asia and Europe!


About CECIDAbout CECID

Center For ECenter For E--Commerce Infrastructure DevelopmentCommerce Infrastructure DevelopmentTechnology focus: Technology focus: XMLXML and and Web ServicesWeb ServicesHKU R&D Center (15+ fullHKU R&D Center (15+ full--time staff)time staff)Primarily funded by Innovation and Technology FundPrimarily funded by Innovation and Technology Fund–– establishment of ebXML infrastructure in HKestablishment of ebXML infrastructure in HK–– business process and information interoperability platformbusiness process and information interoperability platform

To enhance HKTo enhance HK’’s competitiveness in es competitiveness in e--commerce developmentcommerce development–– technology creation and transfer for the communitytechnology creation and transfer for the community–– provision of R&D and training services to businesses and the provision of R&D and training services to businesses and the

government (R&D outsourcing)government (R&D outsourcing)–– participation of international standardization initiativesparticipation of international standardization initiatives


Our R&D StrategyOur R&D Strategy

R&DR&DProductsProducts

Pilot Pilot ProjectsProjects

R&DR&D

EndEndUsersUsers

Production Production DeploymentsDeployments

HK LeadHK LeadProjects / Projects / SIsSIs

InternationalInternationalCollaborationsCollaborations


When Should I Use XML?When Should I Use XML?

When you need a buzzword in your When you need a buzzword in your resume :resume :--))

Thank YouThank YouQ&AQ&A

Email: Email: ytleeytlee@@cecidcecid..hkuhku..hkhkURL: URL: www.www.cecidcecid..hkuhku..hkhk

mailto:[email protected]

http://www.cecid.hku.hk/

http://www.cecid.hku.hk/