1. G O B E Y O N D C O N V E N T I O N WORF: Developing DB2 UDB based Web Services on a Websphere Application Server Kris Van Thillo, ABIS Training & Consulting

2. ©2003 BMC SoftwareJune 3, 2015 2 Agenda J2EE and Web Services Introduction › About Web Services › About Stored Procedures Architecting Web Services › Understand application requirements › The server component model - the client invocation model › WSDL, SOAP and UDDI constructs DB2 Stored Procedures and Web Services › WORF › DB2 XML Extender › Web Services

3. G O B E Y O N D C O N V E N T I O N Introduction Web Services and Stored Procedures

4. ©2003 BMC SoftwareJune 3, 2015 4 Web Services - Definition Web Services are “Software applications identified by a URI, whose interfaces and bindings are are capable of being defined, described and discovered by XML artifacts, supporting direct interactions with other software applications using XML based messages via internet-based protocols.”...

5. ©2003 BMC SoftwareJune 3, 2015 5 Web Services - Standards and based on open standards XML - eXtensible Markup Language SOAP - Simple Object Access Protocol WSDL - Web Services Description Language UDDI - Universal Description, Discovery and Integration

6. ©2003 BMC SoftwareJune 3, 2015 6 Webservices - Execution

7. ©2003 BMC SoftwareJune 3, 2015 7 Web Services - Execution Step 1: Define and build Web Service (method signature) function/operation(s), parameters return value, errors/exceptions Step 2: Deploy Web Service to SOAP router deployment descriptor Step 3: Create client application Java calls SOAP API Step 4: Execute the client application

8. ©2003 BMC SoftwareJune 3, 2015 8 Web Services - Why? Advantages: loosely coupled and coarse-grained service granularity programming language independent, interoperable transport independent mutiple invocation styles: static or dynamic multiple communication styles: synchronous or asynchronous open, extensible, standards based: based on XML composable

9. ©2003 BMC SoftwareJune 3, 2015 9 About Stored Procedures... Stored Procedures

10. ©2003 BMC SoftwareJune 3, 2015 10 Advantages of Stored Procedures Faster execution Reduced network traffic Modular programming Increased security

11. ©2003 BMC SoftwareJune 3, 2015 11 Writing Stored Procedures Languages: Java, C,… Generation with GUI: › Stored Procedure Builder (v7) › Development Center (v8) SQL/PL DB2 UDB v8 supports the dynamic CALL statement

12. G O B E Y O N D C O N V E N T I O N Architecting Web Services

13. ©2003 BMC SoftwareJune 3, 2015 13 Common Web Service Architectures

14. ©2003 BMC SoftwareJune 3, 2015 14 Server component model Client invocation model Server component model › Request-Response and RPC paradigms: use solutions with basic synchronous blocking behaviour e.g. Java classes, EJBs, stored procedures › Fire and Forget: JMS architecture and MDBeans for asynchronous behaviour Client invocation model › Static Proxy, static proxy generated, based on WSDL › Dynamic Proxy › Dynamic Invocation Interface

15. ©2003 BMC SoftwareJune 3, 2015 15 WSDL, SOAP, UDDI Constructs SOAP provides a myriad of constructs! Consider: usage styles › SOAP ‘RPC’ style › SOAP Document style encoding styles › encoded › literal

16. G O B E Y O N D C O N V E N T I O N Stored Procedures and Web Services

17. ©2003 BMC SoftwareJune 3, 2015 17 WORF - Basic Architecture WORF: a piece of software plugged in the Websphere application server used by all DB2 Web Service enterprise applications.

18. ©2003 BMC SoftwareJune 3, 2015 18 The DB2 XML Extender Offers … › Stored Procedures › Triggers › User Defined Functions (UDF) › User Defined Datatypes (UDT) › Supporting tables … to extend DB2 functionality!

19. ©2003 BMC SoftwareJune 3, 2015 19 Two methods (i) XColumn Column data = XML documents DB2 used as XML document repository Validation of XML docs Storing XML docs Search through XML docs

20. ©2003 BMC SoftwareJune 3, 2015 20 Two methods (ii) XCollection DB2 used as database (no XML in DB2) XML is transport language Validation of XML docs Decompose XML docs into data Compose XML docs from data

21. ©2003 BMC SoftwareJune 3, 2015 21 DADs XML document › Validate › DTD-id › Method › Detailed description of data mapping: DB2 vs. XML

22. ©2003 BMC SoftwareJune 3, 2015 22 DB2 Web Services WORF: software plugged in the WebSphere application server used by all DB2 Web Service enterprise applications.

23. ©2003 BMC SoftwareJune 3, 2015 23 Web Service Object Runtime Framework (WORF) Provides for: › Resource-based deployment and invocation, i.e.  DADX based  optionally other resources that help define the web service › Automatic service redeployment › Automatic WSDL and XSD generation › Automatic documentation › Automatic test page generation

24. ©2003 BMC SoftwareJune 3, 2015 24 WORF configuration files description of deployed service servlet mapping service specific config database specs engine

25. ©2003 BMC SoftwareJune 3, 2015 25 DADX Document Access Definition eXtension › XML document › a DADX for each Web Service › Web Service meths: DADX operations › Web Service documentation › Query Description SELECT pfname, plname FROM db2.persons call db2.InPers(:lname, :com)

26. ©2003 BMC SoftwareJune 3, 2015 26 Possible DADX operations / DB2 manipulations › select › insert › update › delete › call › retrieveXML › storeXML SQL based queries XML based queries

27. ©2003 BMC SoftwareJune 3, 2015 27 SOAP request processing by WORF Processing sequence: › loads the DADX › optionally loads a DAD file › replaces query parameters › connects to DB2 › runs the SQL statement › commits the database transaction › formats the result into XML › returns the response in a SOAP envelope

28. ©2003 BMC SoftwareJune 3, 2015 28 DB2 Web Services WORF: software plugged in the WebSphere application server used by all DB2 Web Service enterprise applications.

29. ©2003 BMC SoftwareJune 3, 2015 29 Why will Web Services Succeed? Because: › Implementation de-coupled from interface  any language  open standard transport ‘distributed’ technology › Optimized for Internet  standard based › ‘No’ assumptions about technology at either side of the chain › Backed by key software vendors: IBM, Oracle, MS, etc.