Web Services with WDSCi for Starbase

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Web Services with WDSCi for Starbase
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What is a Web Service

• A programmable application designed to support
  machine-to-machine interaction over a network,
  regardless of machine type, programming language,
  or software application using standard internet
  protocols.

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Web Service Components

• XML
• Web Services Description Language
• Universal Description, Discovery, and Integration
• Simple Object Access Protocol

XML
Format Used For Web Services
WSDL
- How to communicate
- Specific Operations
UDDI
- Discover Web Services
SOAP
- Protocol to Exchange Information
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Web Service Components
Bringing It All Together
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WSDL Components

• Types
• Data Types Definitions
• Messages
• Parameters
• Port Types
• Collection of Operations
• Bindings
• Protocol/Data Format
• Services
• Defines Endpoints

WSDL Interface
Types
- Schema Types
Messages
- Parameters
Port Types
- Operations
Bindings
- Operations/Transport Protocol
WSDL Implementation
Service
- Defines Endpoint
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WSDL Types
ltelement name InventoryIdRequestgt
ltcomplexTypegt ltelement name inventoryId
type string /gt lt/complexTypegt lt/elementgt lte
lement name InventoryCheckResponsegt
ltcomplexTypegt ltelement name
inventoryCount type int /gt
lt/complexTypegt lt/elementgt
Note Types can be embedded schema definitions.
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WSDL Messages
ltmessage name inventoryCheckRequestgt ltpart
name parameter1 element InventoryIdRequ
est /gt lt/messagegt ltmessage name
inventoryCheckResponsegt ltpart name
parameter2 element InventoryCheckResponse
/gt lt/messagegt
Note One or more parts in a message. Message
describe the content that will be sent in the
SOAP operation.
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WSDL PortTypes
ltportType name InventoryCheckServicegt
ltoperation name inventoryCheckgt ltinput
message intfinventoryCheckRequest /gt
ltoutput message
intfinventoryCheckResponse /gt
lt/operationgt lt/portTypegt
Note Operation can be one-way,
request-response, solicit-response, or
notification.
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WSDL Bindings
ltbinding name InvSoapBinding type
intfInventoryCheckServicegt ltbinding
style document transport
http//schema.xmlsoap.org/soap/http /gt
ltoperation name inventoryCheckgt ltinput
name inventoryCheckRequest /gt ltinput
name inventoryCheckResponse /gt
lt/operationgt lt/bindinggt
Note Underlying transport protocol.
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WSDL Service
ltservice name InventoryCheckServiceService
ltport binding intfInvSoapBinding name
InventoryCheckServicegt ltsoapaddress
location http//..... /gt
lt/portgt lt/servicegt
Note Each port definition identifies a single
address for a binding.
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SOAP Components
SOAP Envelope
- Wrapper for message content
SOAP Header - Optional

• Contains control information. Some example
  include
• date message was sent, routing or authentication
  info.

SOAP Body
- Contains actual data
- Error reporting
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SOAP - XML

• lt?xml version"1.0"?gt
• ltsoap envelopegt
• ltsoap bodygt
• ltmethodgt
• ltparametersgtvalue1lt/parametersgt
• lt/methodgt
• lt/soap bodygt
• lt/soap envelopegt

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SOAP - Request

• lt?xml version"1.0"?gt
• ltsoap envelope .gt
• ltbodygt
• ltgetInventoryIdRequestgt
• ltinventoryIdgtabc123zyxlt/invento
  ryIdgt
• lt/getInventoryIdRequestgt
• lt/bodygt
• lt/soap envelopegt

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SOAP - Response

• lt?xml version"1.0"?gt
• ltsoap envelope .gt
• ltbodygt
• ltInventoryCheckResponsegt
• ltinventoryCountgt321lt/inventoryC
  ountgt
• lt/InventoryCheckResponsegt
• lt/bodygt
• lt/soap envelopegt

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Steps to Build Web Service?

• Basic Components
• Build a Service to provide that is capable of
  handling the appropriate calls (i.e. java class
  that can read a SOAP message request and send
  SOAP response).
• Build a WSDL to inform users how to access your
  service.
• Publish or share your WSDL with clients/users.

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Example of a Web Service

• Terra Server USA
• UPS Online Tracking Service
• Information Retrieval such as stock quotes or
  weather conditions.
• Keller Schroeder might use a web service to share
  business logic between an ASP and Java
  application.

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Java SAAJ API

• Use Java SAAJ API to create, send, and receive a
  SOAP message.
• It is a wrapper for XML parsing and can handle
  HTTP calls.
• Provides convenient methods for
  accessing/creating a SOAP message.
• Provides functionality for request/response SOAP
  messages.

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What Can Be Done With WDSC?

• WSDC (WebSphere Development Studio Client for
  iSeries)
• Wizards make it easy to create and use web
  services
• Wizards create Web Services from Java Bean
  (Java2WSDL)
• Generates WSDL
• Creates all required components (XMLs)
• Creates a test client
• Wizards create Web Service from WSDL (WSDL2Java)
• Creates the Java classes required for the Web
  Service
• Creates all required components (XMLs)
• Wizards for creating a Web Service Client

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Resources Sites

• Resources
• W3C
• http//www.w3.org/TR/wsdl
• http//www.w3.org/TR/soap/
• IBM
• http//www-128.ibm.com/developerworks/webservices/
  
• MSDN
• http//msdn.microsoft.com/library/default.asp?url
  /workshop/author/webservice/overview.asp
• Wikipedia (SOAP, WSDL, UDDI)
• iSeries News (July2006)
• http//www.perfectxml.com/WebSvc3.asp
• Web Service Examples
• http//soapclient.com/soaptest.html (Test WSDL)
• http//www.xmethods.net/ (Many sample web
  services)