AD214 XML and Web Services with IBM Lotus Domino and IBM Rational Application Developer. Bob Balaban, Executive Consultant WPLC, IBM Software Group

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1 AD214 XML and Web Services with IBM Lotus Domino and IBM Rational Application Developer Bob Balaban, Executive Consultant WPLC, IBM Software Group

2 Agenda What s XML? What s a Web Service? XML in Domino Web Services demos Domino Rational Application Developer (RAD) Q & A (in another room) And in the Design, Enablement & Implementation lab Dolphin, Europe 3 & 4

3 Introduction: Bob Balaban /G, 123/W, Notes Agent Manager, LotusScript/Java back-end classes for Notes Founded Looseleaf Software, 1987 Wrote many articles Wrote a book ("Programming Domino 4.6 With Java") Wrote some code Re-joined IBM August, 2005 Helping IBM's large customers apply our collaboration software effectively to their problems

4 What s XML? "extensible Markup Language" A way of organizing and structuring arbitrary data So long as the data is text Or values representable as text Tag-based, like HTML But with a different purpose HTML describes rich text for browsers XML describes any data, for any application Typically, not for direct human consumption

5 Simple Example <?xml version="1.0" encoding="iso "?> <OuterTag> <InnerTag attribute="something"> <SomeDataItem>XYZZY</SomeDataItem> </InnerTag> <SingletonTag flag="whatever" /> </OuterTag>

6 Benefits of XML XML allows for arbitrary nesting So long as tags are "balanced" Tag names can be anything So, very flexible, can represent very complex data Remember, it doesn't have to be parsed by humans! And, if EVERYONE obeys the rules... You can use STANDARD tools! You don't have to write them yourself And you can agree with others that you'll use XML to share data

7 Tools for Parsing XML "DOM" parsers: Tree/node orientation You navigate the tree however you want "SAX" parsers: You provide event-oriented callbacks to the parser You don't do the navigation, you get notified when nodes are reached during parser traversal "XPath" parsers: You provide path-like specs for the nodes you want to examine Both DOM and SAX parsers are available in D6 and D7 LotusScript back-end classes Standard Java libraries

8 A Few Words About XSL XML Stylesheet Language This makes "XSL" another DNT!! But if you define it as "extensible Stylesheet Language", it isn't ;-( XSL is really a programming language Defining how to transform XML into other "shapes" HTML, Different XML, CSV, Anything! And... the syntax is XML You already have parsing tools! XSLT = XSL Transform An engine for executing XSL against XML inputs XPATH is actually part of XSL XSLT is part of the Apache Xalan distribution Evolved from LotusXSL But not backward-compatible!

9 The Basic Idea of XSLT Apache Xalan, LotusXSL,... Source XML XSL Style Sheet XSLT Engine Result Tree app processing Result XML Stream one or more templates in the XSL syntax (Thanks to Mark Colan, IBM

10 But, XML By Itself Is Not Enough! We need agreement/conventions at many levels What if your <Document> tag doesn't agree with mine? We either need to agree to use different names... Or, we need to segment the "name space" XML "NameSpaces" "Namespaces"? Create a short, globally unique ID for a collection of element tags (Like a Java "package") <SomeTag xmlns:looseleaf=

11 Namespaces - 2 Then each different kind of Document tag can be qualified by a namespace designation: <SomeTag xmlns:looseleaf=" <Looseleaf:Document>...</Looseleaf:Document> <IBM:Document>...</IBM:Document> </SomeTag>

12 Layers of Convention Above XML Schemas XSD: XML Schema Definition A "DNT"! (doubly-nested TLA (three-letter acronym))* (Thanks to Ned Batchelder!) How many ways are there to create a Purchase Order in XML? Lots But if we can agree on a "schema" definition, we can freely transmit data between our apps See for examples: XML stream can contain a pointer to a schema document <purchaseorder orderdate=" " xmlns=" xmlns:xsi=" xsi:schemalocation=" " >

13 Benefits of XSD Provides structure and semantic above pure syntax E.g., for business objects It s just XML! So there are lots of off-the-shelf tools for it (See for full list & links) XSV: open-source schema validator Dtd2xs: Translator from DTD to XSD SQC: XSD validator from IBM

14 "Web Services"? Web Services are analogous to RPC: "Client" initiates a parameterized request over a network to a "server" Server and target application are locatable over the network (DNS) Request has well-known ID (method name) Request has well-known parameters (primitives, objects...) Response has well-known structure

15 Definition - 2 This architecture has several big advantages: Uses HTTP (and other!) transports XML "wire protocol" allows for vendor (and OS!) independence "Meta" standards for description and publishing allow for additional automation WSDL, UDDI Publish, discover Web Services can be thought of as Business Components Implementations of client (user) and server (provider) are no longer tightly-coupled! Invocation/response are message-based And the message structure is standardized

16 Definition - 3 XML - Data description SOAP - Simple Object Access Protocol XML request/response messaging WSDL - Web Services Description Language XML description of a service And the usual XML Parser suspects! DOM, SAX, XSLT, XPATH... Note: There s nothing about this that requires Java!

17 How Do You Find Web Services? UDDI Universal Description and Discovery Interface The "Yellow Pages" for WSDL Spec is owned by Oasis ( Anyone can implement a public (or private) "Registry")

18 Lots of Tools for Avoiding Typing! Server-side Create a service from a class (Java, LotusScript, VB.NET, C#...), generate WSDL Create a class from WSDL (you still have to type the implementation) Create a service from a database table (DB2, SQL ) Create a service from an EJB Client-side Generate a proxy class from WSDL (Java,.net ) Generate a test client (JSP) from WSDL

19 WebService Development - 1 WebService WebService WebService Application Server

20 WebService Development - 2 WSDL (XML file) WebService WebService WebService Application Server Create WSDL description of your Web Service

21 WebService Development - 3 SOAP Client Implementation WSDL (XML file) WebService WebService WebService Application Server Use WSDL to implement SOAP client code

22 WebService Development - 4 SOAP Client Implementation SOAP Request WSDL (XML file) WebService WebService WebService Application Server Client sends SOAP Invocation to server

23 WebService Development - 5 SOAP Client Implementation SOAP Response SOAP Request WSDL (XML file) WebService WebService WebService Application Server

24 Why Do Web Services Matter? Allows clients and servers to be loosely coupled Implementations are opaque to each other Different platforms, different vendors, doesn t matter! (So long as everyone is using the same transport/wire protocol conventions!) Relatively easy to layer on top of existing code Some re-factoring may be advisable One of the foundations of Services Oriented Architecture (SOA) The more it s used, the more useful it becomes Very flexible transports and protocols (http, smtp, mq, tcp/ip.) BUT. Still no widespread agreement on security standards Single-vendor solutions work well, we need more than that

25 XML In Domino: Demos Embed xml in web pages DNUGSamp.nsf/EmbeddedXML?ReadForm &e=utf-8 Start pass-thru text with the <?xml...?> tag, be careful with "encoding=" attribute Domino does no automatic charset translation You want to think about who is going to read the XML

26 Domino Demos - 2 Use CSS and XSL to format XML data in pages CSS Just embed a reference to the style sheet in the XML DNUGSamp.nsf/EmbeddedXML-CSS?ReadForm <?xml version="1.0" encoding="utf-8"?> <?xml-stylesheet type="text/css" href="bookdisplay.css"?> XSL Embed a reference, as before DNUGSamp.nsf/EmbeddedXML-XSL?ReadForm <?xml version="1.0" encoding="utf-8"?> <?xml-stylesheet type="text/xsl" href="/bookform.xsl"?>

27 Domino Demos - 3 Did you know that Domino HTTP can automatically generate XML for views? DNUGSamp.nsf/XML?ReadViewEntries This is what some of the R5 applets use Many query options, see online help

28 Other Domino Opportunities Document.generateXML() Can pass PrintWriter Can return String Creates "DXL" for document data parsexml() on Item, RichText Item, EmbeddedObject, MimeEntity ONLY IF THEY CONTAIN "raw" XML! Returns org.w3c.dom.document XML DOM tree DXL = Domino XML Language Another DNT!

29 A Brief Digression on DXL DXL utilities translate native Notes data to XML Anything in an NSF Output is the DXL "dialect" of XML And back! Input DXL, create/update NSFs Why would you need Notes data as a DOM tree? E.g., doing Document.generateXML()? Parse document (or Form? View?) as XML Document.generateXML(), pull out interesting bits using XPATH (or XSLT, or DOM, or SAX)... Transform data to something else? Edit? (Including design documents!) Insert? Line up early for Rocky Oliver s DXL presentation! Wednesday 1/25, 4:15pm Swan 5-6

30 Lots and Lots of XML-Related LotusScript Classes NotesDOMParser, NotesSAXParser NotesXSLTransformer NotesDXLExporter, NotesDXLImporter Assisted by NotesNoteCollection, NotesStream NOTE: XML is NOT a native data format for NSF You still need to think about it as an export/import/interchange description of data/design Check out the Looseleaf XML Tutorial Follow the link to the original homepage, find the tutorial link there

31 And Now, The Fun Stuff Web Services Demos 1) Domino 7 Server 2) RADv6 Server and Client Warning: Watch out for land mines! Tip: Create web services with the test server RUNNING Tip: Keep service and client EARs SEPARATE Tip: ALWAYS generate the Java proxy (you will need it later)

32 Resources W3 site has lots of XML standards info xml.apache.org Open source tools, SOAP, Web Services Standards consortium, specializing in Web Services java.sun.com lots of free Java based tools msdn.microsoft.com/xml COM based libs (can be used with LotusScript!) Books, tutorials...

33 More Resources "Just XML", John E. Simpson, Prentice Hall, 1999 "XSLT Programmer's Reference", Michael Kay, Wrox Press, 2000 XML Journal - Lotus Advisor, WebSphere Advisor The View Redbook "XML Powered by Domino How to use XML with Lotus Domino" Mark Colan's "speaker" page com/developerworks/ speakers/ colan Brian Benz's Web site Co-author of the "Domino and XML" redbook

34 Recommended Sessions Christian Holsing Line up early for Rocky Oliver s DXL presentation (BP313) Wednesday 1/25, 4:15pm Swan 5-6 Domino 7 Web Services Hands-on Lab (HND205) Balaban & Hobert Swan Osprey 2 Tuesday 24 th, 8:30am and Thursday 26 th, 8:30am Advanced Coding Techniques for Domino in J2EE Balaban Dolphin SHemisphere 4-5 Tuesday 24 th, 3:00pm

35 Thank You! Q & A (in another room) And in the Design, Enablement & Implementation lab Dolphin, Europe 3 & 4 (Come see the more detailed SAP integration demo)

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XML Programming Duration: 5 Days US Price: $2795 UK Price: 1,995 *Prices are subject to VAT CA Price: CDN$3,275 *Prices are subject to GST/HST Delivery Options: Attend face-to-face in the classroom or