Transcript WSDL-Web Service Description Language

WSDL-Web Service Description
Language
By Shin Chuan , Lin
July / 8 /2003
Topic Covered
 Introduction
 Structure of WSDL document
 Example of WSDL
 Difference between WSDL 1.2 and WSDL
1.1
 How to use WSDL file ?
 Reference
Introduction
 What is WSDL ?
Stands for Web Service Description Language
It’s an XML document for describing web services
Further considers that an interface represents the
behavior of a resource on the World Wide Web
 What can we know from WSDL ?
What kind of message is exchanged ?
How are the message related ?(e.q operation input or output)
How SOAP messages are exchanged ?
What is WSDL ?
Structure of WSDL document
 Type
“Interface” definition
 Messages
 interfaces(Port Types)WSDL1.2
 Bindings
Protocol – html , smtp
Encoding
 Service
“endpoint” definition
Structure of WSDL document
<definitions>
<types>definition of types</types>
<message>definition of message</message>
<interface>definition of interface</interface>
<binding>definition of biding</binding>
<services>definition of endpoint </endpoint>
</definitions>
Structure of WSDL
document :definitions
 Definitions Component is just a container for two
categories of component:
(1)WSDL Component: messages, interface , binding and
services
(2)Type System Component: element declartions and type
definitions drawn from some type system .
 Definitions are represented in XML by one or more
WSDL information Sets(Infosets).
A WSDL InfoSet contains representations of a collection of
WSDL components which share a common target
namespace.
Structure of WSDL
document :Types
 The types element encloses data type definitions
that are relevant for the exchanged messages.
WSDL prefers the use of XML Schema .
 FROM
<type>
<xsd:schema …/>
</type>
An Example of WSDL Types
<tpyes>
<schema targetNamespace = “http://examploe.com/stockquote.xsd”>
<element name=“TradePrice”>
<all>
<element name=“price” type=“float”/>
</all>
</complex Type>
</element>
</schema>
</type>
Note: (1) Use element form
(2) Array types should extend the Array type from SOAP v1.1 encoding
schema ( http://schemas.xmlsoap.org/soap/encoding)
Structure of WSDL
document :Message
 The message component describes the abstract
format of a particular message that Web service
sends or receives .
 Combine with binding to describe how the abstract
content is mapped into a concrete format .
 From:
<messages name = “”>
<target namespace>
<part name = “” element= “” type =“”?/>
…
<message>
An Example of WSDL
Message
<message name=“InputParameters”>
<part name = “firstname” type=“xsd:string”/>
<part name = “age” type=“xsd:int”/>
</message>
<message name=“OutputParameters”>
<part name=“id” type=“xsd:int”/>
</message>
What does this mean ?
Int get_id(string firstname , int age)
An Example of WSDL
Message
name :
local name of message
part component :
describes a portion of a particular message that a
web service sends or receives .
type :
describe the format of a part
element : carrier information about its type system
Structure of WSDL
document :interface
 The interface element is core WSDL element . It
describes a set of messages that a service sends
and/or receives , by grouping related messages into
operations.
 Operations include :
One-way transmissionThe endpoint receives a message
Request-response
The endpoint receives a message and
sends a correlated message
Solicit-Response
The endpoint sends a message and
receives correlated message .
Notification
The endpoint sends a messge
Structure of WSDL
document :interface
 Form:
<definitions>
<interface>
<operation
name =“xs:NCNAME”
pattern=“xs:anyURI”
<documentation/>?
[ <feature/> | <property/> |
[<input/> | <output/> | <infault /> | <outfault/>]+
]*
</operation>
</interface>
</definitions>
Structure of WSDL
document :interface(cont1)
Operation :
An interface operation component describes an operation
that a given interface supports. An operation is a set of
message references and an associated message pattern.
Message references are references either to messages
accepted by this operation(input message) ,or messages
send by this operation(output messages) . Such messages
could be ordinary messages or fault messages .
fault element specify the abstract message format for any error
messages that may be output as the result of the operation
Structure of WSDL
document :interface(cont2)
{message pattern} A URI identifying the message pattern used
by the operation.
{message references}A set of message reference components
for the ordinary messages the operation accepts or send .
{fault references}A set of fault reference components for the
fault messages the operation accepts or sends.
{features} A set of named feature definitions used by the
operation
{properties} A set of named property definitions used by the
operation.
Example of interface
<interface name="TicketAgent">
<operation name="listFlights“
parameterOrder="depart origin destination">
<input message=
"tns:listFlightsRequest"
name= "listFlightsRequest"/>
<output message=
"tns:listFlightsResponse“
name= "listFlightsResponse"/>
</operation>
Example of interface(cont1)
<operation name =
"reserveFlight“
parameterOrder=
"depart origin destination flight">
<input message=
"tns:reserveFlightRequest“
name= "reserveFlightRequest"/>
<output message=
"tns:reserveFlightResponse“
name="reserveFlightResponse"/>
</operation>
</interface>
Structure of WSDL
document :Bindings
 A binding defines message format and
protocol details for operations and messages
defined by a particular interface .
 WSDL (Version 1.2): Bindings [WSDL 1.2 Bindings]
defines such bindings for SOAP 1.1 [SOAP 1.1], SOAP
1.2 [SOAP 1.2 Part 1: Messaging Framework], HTTP
[IETF RFC 2616] and MIME [IETF RFC 2045]. Other
specifications MAY define additional binding details
Structure of WSDL
document :Bindings
From
<binding name=““ interface=“”>
<operation name=“”>
<input name=“”?></input>
<output name=“”?></output>
<fault name=“”></fault>
</operation>
</binding>
Note : A binding MUST specify exactly one protocol
Example of binding
<binding name=“Binding1” type=“record”>
<soap:binding style=“document”
Transport=http://schemas.xmlsoap.org/soap/http/>
<operation name=“get_id”>
<soap:operation
soapAction =“http://example.com/get_id”>
<input>
<soap:body use =“literal”/>
</input>
<output>
<soap:body use=“literal”/>
</output>
</operation>
</binding>
Structure of WSDL
document :Service
 A service component describes one and only
one interface that a service provides, and the
endpoints it is provided over.
Structure of WSDL
document :Service
Forms:
<definitions>
<service name= "xs:NCName"
interface="xs:QName"
targetResource="xs:anyURI"? >
<documentation />?
<endpoint />*
</service>
</definitions>
Structure of WSDL
document :Service
 An endpoint component defines the particulars of a
specific end-point at which a given service is
available.
The properties of the Endpoint Component are as
follows:
 {name} An NCName as defined by [XML Namespaces].
 {binding} A named binding component
For each endpoint component in the {endpoints} property of a service
component the {name} property must be unique.
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<?xml version="1.0"?>
<definitions name="StockQuote“
targetNamespace=http://example.com/stockquote.w
sdl
xmlns:tns=http://example.com/stockquote.wsdl
xmlns:xsd1=http://example.com/stockquote.xsd
xmlns:soap=http://schemas.xmlsoap.org/wsdl/soap/
xmlns="http://schemas.xmlsoap.org/wsdl/">
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<message name="SubscribeToQuotes">
<part name="body“
element="xsd1:SubscribeToQuotes"/>
<part name="subscribeheader“
element="xsd1:SubscriptionHeader"/>
</message>
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<interface name="StockQuoteInterface">
<operation name="SubscribeToQuotes">
<input message="tns:SubscribeToQuotes"/>
</operation>
</interface>
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<binding name="StockQuoteSoap“
type="tns:StockQuoteInterface">
<soap:binding style="document“
transport="http://example.com/smtp"/>
<operation name="SubscribeToQuotes">
<input message="tns:SubscribeToQuotes">
<soap:body parts="body" use="literal"/>
<soap:header message="tns:SubscribeToQuotes“
part="subscribeheader" use="literal"/>
</input> </operation></binding>
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<service name="StockQuoteService">
<endpoints name="StockQuoteEndpoint“
binding="tns:StockQuoteSoap">
<soap:address
location="mailto:[email protected]"/>
</endpoints>
</service>
Example of WSDL
SOAP binding of one-way operation over SMTP
using a SOAP Header
<types>
<schema targetNamespace=http://example.com/stockquote.xsd
xmlns="http://www.w3.org/2000/10/XMLSchema">
<element name="SubscribeToQuotes">
<complexType><all>
<element name="tickerSymbol" type="string"/>
</all></complexType></element>
<element name="SubscriptionHeader" type="uriReference"/>
</schema></types>
</definitions>
What does it mean?
 In the above example , a SubscribeToQuotes
SOAP 1.1 one-way message is sent to a
StockQuote service via a SMTP binding. The
request takes a ticker symbol of type string,
and includes a header defining the
subscription URI.
Difference between WSDL1.2
and WSDL1.1
 Operation Overloading
WSDL 1.1 supported operation overloading and
WSDL 1.2 removes it. This section will provide
some rationale for it and provide hints on how to
work around some scenarios.
 PortTypes
Port types have been renamed to interfaces. We
now have interface inheritance.
 Ports
Ports have been renamed to endpoints.
Conclusion(How to use wsdl?)




EX: How to use Google API with WSDL ?
Google provide standard wsdl file
http://api.google.com/GoogleSearch.wsdl
How to use wsdl file?
Many programming languages now understand WSDL and can use this
file to automatically invoke Google's API. For example, the WSDL can
be imported into .NET, converted into Java code using Apache Axis
WSDL2Java, or used directly by Perl SOAP::Lite. The WSDL file has
been tested with SOAP::Lite 0.52, the .NET Framework, (via "Add Web
Reference" or wsdl.exe version 1.0.3705.0), and Apache Axis Beta 1.
How to use wsdl?
Use Google with Perl Example :
use SOAP::Lite;
my $key='000000000000000000000000';
my $query="foo";
my $googleSearch = SOAP::Lite ->
service("file:GoogleSearch.wsdl");
my $result = $googleSearch -> doGoogleSearch($key,
$query, 0, 10, "false", "", "false", "", "latin1", "latin1");
print "About $result->{'estimatedTotalResultsCount'}
results.\n";
How to use wsdl?
 What is SOAP::Lite ?
 SOAP::Lite makes the request for service
description, parses it, builds the stub (object
that make available the same methods as
remote service) and returns it to you.
How to use wsdl?
Example :
#!perl -w
use SOAP::Lite;
my $service = SOAP::Lite ->
service(‘http://api.google.com/GoogleSearch.wsdl');
print ‘ReturnByMSFT + ReturnByORCL = ',
$service->getQuote(‘ReturnByMSFT') +
$service->getQuote(‘ReturnByORCL');
How to use wsdl?
 You may also use your local computer with
multiple wsdl file ..
 Example :
#!perl -w
use SOAP::Lite
service =>’http://api.google.com/GoogleSearch.wsdl ',
#service=>'file:/your/local/path/GoogleLocal.wsdl‘
, # service => 'file:./yourOwnService.wsdl', ;
print getQuote(‘RetrunByMSFT'), "\n";
More Detail please check : http://www.soaplite.com/
References
Web Services Description Language (WSDL) 1.1
W3C Note 15 March 2001 :
[http://www.w3.org/TR/2001/NOTE-wsdl-20010315 ]
Web Services Description Language (WSDL) Version 1.2 Part 1: Core Language
W3C Working Draft 11 June 2003
[http://www.w3.org/TR/2003/WD-wsdl12-20030611 ]
Web service :
[http://ru.sun.com/win/developers/std02/presentations/ritter3.pdf]
WSDL overview:
[http://www.intl-interfaces.com/servicemodel/WSDLOverview1.pdf]
Web Service
Web Service Description Language
[www.ti5.tu-harburg.de/Lecture/03ss/SEM/030505/ 030505MariuszChechelski_slides.pdf ]
SOAP::Lite for Perl [http://www.soaplite.com/ ]
Google API package readme.txt [http://www.google.com/apis/download.html]