WSDL 2.0

Why Should We Care About
WSDL 2.0?

by
Philippe Le Hégaret
(W3C)

WSDL ?!?

Web Services

Web Services
Description

Web Services
Description
Language

WSDL

Web Services?

Computer
-to-
computer
interaction

Language neutral

Java

C#

Transport neutral

HTTP

JMS

UDP

SOAP

XML
Envelope

Why SOAP?

Code generation

Tools

interface reservation
{
 aResult checkAvailability(aRequest);
}

Language Independent

Web Services Description

Interfaces
and
Operations

XML

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

Schema Language

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

XML Schema

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

Faults

<interface name="reservation">
 <fault name='f' element='#any'/>
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
   <outfault ref="f" />
 </operation>
</interface>

Protocol

<binding
 name="reservationBinding" 
 interface="tns:reservation">
 
</binding>

Protocol

SOAP

<binding
 name="reservationSOAPBinding" 
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/soap"
 wsoap:protocol="http://www.w3.org/2003/05/soap/bindings/HTTP/">
 
</binding>

Transport
Protocol

over HTTP

<binding
 name="reservationSOAPBinding" 
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/soap"
 wsoap:protocol="http://www.w3.org/2003/05/soap/bindings/HTTP/">
 
</binding>

Protocol neutral

HTTP

HTTP
only

<binding
 name="reservationHTTPBinding"
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/http">
</binding>

Default is
HTTP POST

XML
in the
HTTP BODY

HTTP GET

From
XML

to
URI

http://example.org
/services/Premium?
checkIn=2007-06-01
&checkOut=2007-06-01

URI Mapping

<interface name="reservation" >
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<xs:element name='aRequest'>
  <xs:complexType>     
    <xs:sequence>      
      <xs:element name="checkInDate" type="xs:date"/>      
      <xs:element name="checkOutDate" type="xs:date"/>      
      <xs:element name="roomType" type="xs:string"/>      
    </xs:sequence>     
  </xs:complexType>
</xs:element>

<xs:element name='aRequest'>
  <xs:complexType>     
    <xs:sequence>      
      <xs:element name="checkInDate" type="xs:date"/>      
      <xs:element name="checkOutDate" type="xs:date"/>      
      <xs:element name="roomType" type="xs:string"/>
    </xs:sequence>     
  </xs:complexType>
</xs:element>

<xs:element name='aRequest'>
  <xs:complexType>     
    <xs:sequence>      
      <xs:element name="checkInDate" type="xs:date"/>      
      <xs:element name="checkOutDate" type="xs:date"/>      
      <xs:element name="roomType" type="xs:string"/>
    </xs:sequence>     
  </xs:complexType>
</xs:element>

<xs:element name='aRequest'>
  <xs:complexType>     
    <xs:sequence>      
      <xs:element name="checkInDate" type="xs:date"/>      
      <xs:element name="checkOutDate" type="xs:date"/>      
      <xs:element name="roomType" type="xs:string"/>
    </xs:sequence>     
  </xs:complexType>
</xs:element>

<xs:element name='aRequest'>
  <xs:complexType>     
    <xs:sequence>      
      <xs:element name="checkInDate" type="xs:date"/>      
      <xs:element name="checkOutDate" type="xs:date"/>      
      <xs:element name="roomType" type="xs:string"/>
    </xs:sequence>     
  </xs:complexType>
</xs:element>

<aRequest>
  <checkInDate>2006-06-01</checkInDate>
  <checkOutDate>2006-06-03</checkOutDate>
  <roomType>Premium</roomType>
</aRequest>

?checkInDate=2007-06-01
&checkOutDate=2007-06-03
&roomType=Premium

<binding
 name="reservationHTTPBinding"
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/http">
 <operation ref="tns:checkAvailability"
   whttp:method="GET" />
</binding>

<binding
 name="reservationHTTPBinding"
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/http"
 whttp:methodDefault="GET">

</binding>

/services/Premium?
checkIn=2007-06-01
&checkOut=2007-06-01

<binding
 name="reservationHTTPBinding"
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/http">
 <operation ref="tns:checkAvailability"
   whttp:method="GET"
   whttp:location="/services/{roomType}
          ?checkIn={checkInDate}
          &checkOut={checkOutDate}" />
</binding>

WSDL

WSDL 1.1

Widly deployed

Widly
mis-interpreted

Follow
WS-I
Basic
Profile 1.0

WSDL 2.0

Based on
WSDL 1.1
experience

Better defined

WSDL 2.0
Component Model

layer of
abstraction

Reuse

Inheritance

<interface name="reservation"
       extends='tns:metaService'>
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<interface name="reservation"
       extends='tns:metaService
                fr:metaService2'>
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

Include
(WSDL 1.1)

<include location="interfaces.wsdl">
</include>

Same Namespace

Import

<import
   namespace='http://example.org/'
   location="interfaces.wsdl">
</import>

Multiple
Namespaces

<interface name="reservation"
       extends='tns:metaService
                fr:metaService2'>
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

Message
Exchange
Patterns

MEPs

<interface name="…">
 <operation name="…">
   [ <input /> | <output /> ]*
 </operation>
</interface>

3 MEPs

1. Robust-In-Only

<interface name="reservation">
 <operation name="checkAvailability"
   pattern='http://www.w3.org/ns/wsdl/robust-in-only'>
   <input element="sc:aRequest" />
 </operation>
</interface>

In-Only
+ optional Fault

<interface name="reservation">
 <fault name='f' element='#any'/>
 <operation name="checkAvailability"
   pattern='http://www.w3.org/ns/wsdl/robust-in-only'>
   <input element="sc:aRequest" />
   <outfault ref='tns:f'/>
 </operation>
</interface>

<interface name="reservation">
 <operation name="checkAvailability"
   pattern='http://www.w3.org/ns/wsdl/robust-in-only'>
   <input element="sc:aRequest" />
 </operation>
</interface>

2. In-Only

<interface name="reservation">
 <operation name="checkAvailability"
   pattern='http://www.w3.org/ns/wsdl/robust-in-only'>
   <input element="sc:aRequest" />
 </operation>
</interface>

Send
and
Move on

3. In-Out

<interface name="reservation">
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

<interface name="reservation">
 <fault name='f' element='#any'/>
 <operation name="checkAvailability">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
   <outfault ref="f" />
 </operation>
</interface>

Bindings

SOAP

SOAP 1.1

SOAP 1.1
SOAP 1.2

SOAP 1.2
MEPs

In-Out
to
Request-Response

In-Out
to
SOAP-Response

In-Only
to
Request-Response

Robust-In-Only
to
Request-Response

HTTP

Content-Encoding

<operation ref="tns:checkAvailability"
   whttp:contentEncoding="gzip"
  />

Headers

<operation ref="tns:checkAvailability">
   <whttp:header
     name="X-Auth"
     type="xs:string"
     required="true" />
   
</operation>

Authentication

<endpoint name="HTTPendpoint"
 binding="tns:reservationHTTPBinding"
 address="http://myservice.com/services/" >
   whttp:authenticationScheme="digest"
   whttp:authenticationRealm="Member" />

SOAP
over HTTP

<binding
 name="reservationSOAPBinding" 
 interface="tns:reservation"
 type="http://www.w3.org/ns/wsdl/soap"
 wsoap:protocol="http://www.w3.org/2003/05/soap/bindings/HTTP/">
 <operation ref="tns:checkAvailability"
   whttp:location="/services/{roomType}
          ?checkIn={checkInDate}
          &checkOut={checkOutDate}">
   <whttp:header
     name="X-Auth" type="xs:string"
     required="true" />
 </operation> 
</binding>

Serialization
Formats

application/
x-www-form-
urlencoded

multipart/form-data

Safety
Feature

<interface name="reservation">
 <operation name="checkAvailability"
            wsdlx:safe="true">
   <input element="sc:aRequest" />
   <output element="sc:aResult" />
 </operation>
</interface>

HTTP GET

Testing

WSDL 1.1
to
WSDL 2.0
converter

Full
SOAP support

Full
HTTP support

Full
SOAP
over HTTP
support

Describe
Web Services

Describe
Web Applications

WSDL 2.0
Summer 2007

http://www.w3.org/2007/Talks/0508-w3ctrack-plh-2/