W3C

Web Services Addressing - WSDL Binding

W3C Working Draft 8 December 2004

This version:
http://www.w3.org/TR/2004/WD-ws-addr-wsdl-20041208
Latest version:
http://www.w3.org/TR/ws-addr-wsdl
Previous versions:
Editors:
Martin Gudgin, Microsoft Corp
Marc Hadley, Sun Microsystems, Inc

This document is also available in these non-normative formats: postscript, PDF
, XML, and plain text.

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Abstract

Web Services Addressing provides transport-neutral mechanisms to address Web
services and messages. Web Services Addressing WSDL Binding (this document)
defines how the abstract properties defined in Web Services Addressing Core are
described using WSDL.

Status of this Document

This section describes the status of this document at the time of its
publication. Other documents may supersede this document. A list of current W3C
publications and the latest revision of this technical report can be found in
the W3C technical reports index at http://www.w3.org/TR/.

This is the First Public Working Draft of the Web Services Addressing - WSDL
Binding specification for review by W3C members and other interested parties.
It has been produced by the Web Services Addressing Working Group (WG), which
is part of the W3C Web Services Activity.

In this Working Draft, the Web Services Addressing Working Group has, in
keeping with its charter, separated the WS-Addressing Member Submission into
three separate specifications: Core, SOAP Binding, and WSDL Binding. The
Working Group expects to publish an updated draft in the near future
incorporting more resolutions from its issues list.

Discussion of this document takes place on the public public
public-ws-addressing@w3.org mailing list (public archive). Comments on this
specification should be sent to this mailing list.

This document was produced under the 5 February 2004 W3C Patent Policy. The
Working Group maintains a public list of patent disclosures relevant to this
document; that page also includes instructions for disclosing [and excluding] a
patent. An individual who has actual knowledge of a patent which the individual
believes contains Essential Claim(s) with respect to this specification should
disclose the information in accordance with section 6 of the W3C Patent Policy.

Per section 4 of the W3C Patent Policy, Working Group participants have 150
days from the title page date of this document to exclude essential claims from
the W3C RF licensing requirements with respect to this document series.
Exclusions are with respect to the exclusion reference document, defined by the
W3C Patent Policy to be the latest version of a document in this series that is
published no later than 90 days after the title page date of this document.

Publication as a Working Draft does not imply endorsement by the W3C
Membership. This is a draft document and may be updated, replaced or obsoleted
by other documents at any time. It is inappropriate to cite this document as
other than work in progress.

┌──────────────────────────────────────┬──────────────────────────────────────┐
│Editorial note │ │
├──────────────────────────────────────┴──────────────────────────────────────┤
│The Web Services Addressing Working Group has decided to use XML Schema, │
│where appropriate, to describe constructs defined in this specification. Note│
│that this restricts use of Web Services Addressing to XML 1.0. │
└─────────────────────────────────────────────────────────────────────────────┘
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Short Table of Contents

1. Introduction
2. Endpoint References
3. Associating Action with WSDL Operations
4. WS-Addressing and WSDL Message Exchange Patterns
5. References
A. Acknowledgements (Non-Normative)
B. Change log (Non-Normative)

Table of Contents

1. Introduction
1.1 Notational Conventions
1.2 Namespaces
2. Endpoint References
2.1 Information Model for Endpoint References
3. Associating Action with WSDL Operations
3.1 Explicit Association
3.2 Default Action Pattern
4. WS-Addressing and WSDL Message Exchange Patterns
4.1 WSDL 1.1 Message Exchange Patterns
4.2 WSDL 2.0 Message Exchange Patterns
5. References

Appendices

A. Acknowledgements (Non-Normative)
B. Change log (Non-Normative)

1. Introduction

Web Services Addressing CoreWS-Addressing-Core defines a set of abstract
properties and an XML Infoset [XML Information Set] representation thereof to
identify Web service endpoints and to secure end-to-end identification of
endpoints in messages. Web Services Addressing WSDL Binding (this document)
defines how the abstract properties defined in Web Services Addressing Core are
described using WSDL.

1.1 Notational Conventions

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
"SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be
interpreted as described in RFC 2119 [IETF RFC 2119].

When describing abstract data models, this specification uses the notational
convention used by the XML Infoset [XML Information Set]. Specifically,
abstract property names always appear in square brackets (e.g., [some
property]).

When describing concrete XML schemas [XML Schema Structures, XML Schema
Datatypes], this specification uses the notational convention of WS-Security [
WS-Security]. Specifically, each member of an element's [children] or
[attributes] property is described using an XPath-like notation (e.g., /
x:MyHeader/x:SomeProperty/@value1). The use of {any} indicates the presence of
an element wildcard (<xs:any/>). The use of @{any} indicates the presence of an
attribute wildcard (<xs:anyAttribute/>).

1.2 Namespaces

This specification uses a number of namespace prefixes throughout; they are
listed in Table 1-1. Note that the choice of any namespace prefix is arbitrary
and not semantically significant (see [XML Namespaces ]).

Table 1-1. Prefixes and Namespaces used in this
specification
┌──────┬────────────────────────────────────────┐
│Prefix│Namespace │
├──────┼────────────────────────────────────────┤
│S │http://www.w3.org/2003/05/soap-envelope │
├──────┼────────────────────────────────────────┤
│S11 │http://schemas.xmlsoap.org/soap/envelope│
├──────┼────────────────────────────────────────┤
│wsa │http://www.w3.org/2004/12/addressing │
├──────┼────────────────────────────────────────┤
│xs │http://www.w3.org/2001/XMLSchema │
└──────┴────────────────────────────────────────┘

WS-Addressing is defined in terms of the XML Information Set [XML Information
Set]. WS-Addressing is designed to be able work with WSDL 2.0 [WSDL 2.0] and
also (for backwards compatibility with WSDL 1.1 [WSDL 1.1] described services.
WS-Addressing may be used with SOAP [SOAP 1.2 Part 1: Messaging Framework] as
described in Web Services Addressing - SOAP Binding[WS-Addressing-SOAP]. The
examples in this specification use an XML 1.0 [XML 1.0] representation but this
is not a requirement.

All information items defined by WS-Addressing are identified by the XML
namespace URI [XML Namespaces] "http://www.w3.org/2004/12/addressing". A
normative XML Schema [XML Schema Structures, XML Schema Datatypes] document can
be obtained by dereferencing the XML namespace URI.

2. Endpoint References

This specification introduces a new description element type, the endpoint
reference, with the intent of supporting a set of dynamic usage patterns not
currently appropriately covered by WSDL 1.1 [WSDL 1.1].

To support these scenarios, we define a lightweight and extensible mechanism to
dynamically identify and describe service endpoints and instances. Because of
the current limits of the WSDL 1.1 extensibility model, the WSDL 1.1 service
and port elements cannot be used to cover the use cases listed above. Endpoint
references logically extend the WSDL description model (e.g., portTypes,
bindings, etc.), but do not replace it. Endpoint references will be used
instead of WSDL <service/> elements in the following cases:

• Specific instances of a stateful service need to be identified or its
instance-specific configuration details need to be transmitted.

• A lightweight, self-contained description of a service endpoint needs to be
communicated. In particular, this may be necessary when the details of the
endpoint configuration are already shared by the communicating parties, but
specific policy information needs to be added or updated, typically as a
result of a dynamic configuration process.

Endpoint references complement and do not replace the WSDL/1.1 <wsdl:service>
element. We expect solutions built on WSDL/1.1 to continue to utilize a service
element. Moving forward we anticipate that endpoint references and WSDL will
evolve coherently. The endpoint references may link to service elements in WSDL
/1.1, and support additional scenarios in which the WSDL information is not
known by a party processing a message. These scenarios may include dynamic
messaging or limited capability message processors.

2.1 Information Model for Endpoint References

The WSDL binding of Web Services Addressing introduces the following additional
abstract properties:

[selected port type] : QName (0..1)

The QName of the primary portType of the endpoint being conveyed.

[service-port] : (QName, NCName (0..1)) (0..1)

This is the QName identifying the WSDL service element that contains the
definition of the endpoint being conveyed. The service name provides a link
to a full description of the service endpoint. An optional non-qualified
name identifies the specific port in the service that corresponds to the
endpoint.

3. Associating Action with WSDL Operations

WS-Addressing defines two mechanisms to associate an action with input, output
and fault elements within a WSDL port type.

3.1 Explicit Association

The action may be explicitly associated using the wsa:Action attribute or in
the absence of the attribute the action is defined by the rule in section
3.3.2.

For example consider the following WSDL excerpt:

Example 3-1. Explicit specification of wsa:Action value in a WSDL description.

The action for the input of the GetLastTradePrice operation within the
StockQuotePortType is explicitly defined to be http://example.com/GetQuote. The
action for the output of this same operation is http://example.com/Quote.

3.2 Default Action Pattern

In the absence of the wsa:Action attribute, the following pattern is used to
construct a default action for inputs and outputs. The general form of an
action URI is as follows:

Example 3-2. Structure of defaulted wsa:Action URI.

[target namespace]/[port type name]/[input|output name]

The "/" is a literal character to be included in the action. The values of the
properties are as defined below.

[target namespace] is the target namespace (/definition/@targetNamespace). If
[target namespace] ends with a "/" an additional "/" is not added.

[port type name] is the name of the port type (/definition/portType/@name).

[input|output name] is the name of the element as defined in Section 2.4.5 of
WSDL 1.1.

For fault messages, this pattern is not applied. Instead, the following URI is
the default action URI for fault messages: http://www.w3.org/2004/12/addressing
/fault

For example consider the following WSDL excerpt:

Example 3-3. Example WSDL without explicit wsa:Action values with explicit
message names.

[targetNamespace] = http://example.com/stockquote

[port type name] = StockQuotePortType

[input name] = GetQuote

[output name] = Quote

Applying the pattern above with these values we have:

input action = http://example.com/stockquote/StockQuotePortType/GetQuote

output action = http://example.com/stockquote/StockQuotePortType/Quote

WSDL defines rules for a default input or output name if the name attribute is
not present. Consider the following example:

Example 3-4. Example WSDL without explicit wsa:Action values or explicit
message names.

[targetNamespace] = http://example.com/stockquote

[port type name] = StockQuotePortType

According to the rules defined in WSDL 2.4.5, if the name attribute is absent
for the input of a request response operation the default value is the name of
the operation "Request" appended.

[input name] = GetLastTradePriceRequest

Likewise, the output defaults to the operation name with "Response" appended.

[output name] = GetLastTradePriceResponse

Applying the pattern above with these values we have:

input action = http://example.com/stockquote/StockQuotePortType/
GetLastTradePriceRequest

output action = http://example.com/stockquote/StockQuotePortType/
GetLastTradePriceResponse

4. WS-Addressing and WSDL Message Exchange Patterns

TBD

4.1 WSDL 1.1 Message Exchange Patterns

TBD

4.2 WSDL 2.0 Message Exchange Patterns

TBD

5. References

[WS-Addressing-Core]
Web Services Addressing - Core, M. Gudgin, M. Hadley, Editors.
[WS-Addressing-SOAP]
Web Services Addressing - SOAP Binding, M. Gudgin, M. Hadley, Editors.
[WSDL 2.0]
Web Services Description Language 2.0, TBD.
[IETF RFC 2119]
Key words for use in RFCs to Indicate Requirement Levels, S. Bradner,
Author. Internet Engineering Task Force, June 1999. Available at http://
www.ietf.org/rfc/rfc2119.txt.
[RFC 2396bis]
T. Berners-Lee, et al, "Uniform Resource Identifier (URI): Generic
Syntax,", W3C/MIT, July 2004. (See http://www.ietf.org/internet-drafts/
draft-fielding-uri-rfc2396bis-07.txt.)
[XML 1.0]
Extensible Markup Language (XML) 1.0 (Second Edition), T. Bray, J. Paoli,
C. M. Sperberg-McQueen, and E. Maler, Editors. World Wide Web Consortium,
10 February 1998, revised 6 October 2000. This version of the XML 1.0
Recommendation is http://www.w3.org/TR/2000/REC-xml-20001006. The latest
version of XML 1.0 is available at http://www.w3.org/TR/REC-xml.
[XML Namespaces]
Namespaces in XML, T. Bray, D. Hollander, and A. Layman, Editors. World
Wide Web Consortium, 14 January 1999. This version of the XML Information
Set Recommendation is http://www.w3.org/TR/1999/REC-xml-names-19990114. The
latest version of Namespaces in XML is available at http://www.w3.org/TR/
REC-xml-names.
[XML Information Set]
XML Information Set, J. Cowan and R. Tobin, Editors. World Wide Web
Consortium, 24 October 2001. This version of the XML Information Set
Recommendation is http://www.w3.org/TR/2001/REC-xml-infoset-20011024. The
latest version of XML Information Set is available at http://www.w3.org/TR/
xml-infoset.
[XML Schema Structures]
XML Schema Part 1: Structures, H. Thompson, D. Beech, M. Maloney, and N.
Mendelsohn, Editors. World Wide Web Consortium, 2 May 2001. This version of
the XML Schema Part 1 Recommendation is http://www.w3.org/TR/2001/
REC-xmlschema-1-20010502. The latest version of XML Schema Part 1 is
available at http://www.w3.org/TR/xmlschema-1.
[XML Schema Datatypes]
XML Schema Part 2: Datatypes, P. Byron and A. Malhotra, Editors. World Wide
Web Consortium, 2 May 2001. This version of the XML Schema Part 2
Recommendation is http://www.w3.org/TR/2001/REC-xmlschema-2-20010502. The
latest version of XML Schema Part 2 is available at http://www.w3.org/TR/
xmlschema-2.
[SOAP 1.2 Part 1: Messaging Framework]
SOAP Version 1.2 Part 1: Messaging Framework, M. Gudgin, M. Hadley, N.
Mendelsohn, J-J. Moreau, H. Frystyk Nielsen, Editors. World Wide Web
Consortium, 24 June 2003. This version of the "SOAP Version 1.2 Part 1:
Messaging Framework" Recommendation is http://www.w3.org/TR/2003/
REC-soap12-part1-20030624/. The latest version of "SOAP Version 1.2 Part 1:
Messaging Framework" is available at http://www.w3.org/TR/soap12-part1/.
[WSDL 1.1]
E. Christensen, et al, Web Services Description Language (WSDL) 1.1, March
2001.
[WS-Security]
OASIS, Web Services Security: SOAP Message Security, March 2004.

A. Acknowledgements (Non-Normative)

TBD

B. Change log (Non-Normative)

┌──────────┬───────┬──────────────────────────────────────────────────────────┐
│ Date │Editor │ Description │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│2004-11-23│ │Updated titles of examples. Fixed table formatting and │
│@ 21:38 │mhadley│references. Replaced uuid URIs with http URIs in examples.│
│ │ │Added document status. │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│2004-11-11│mgudgin│Added some TBD sections │
│@ 18:31 │ │ │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│ │ │Second more detailed run through to separate core, SOAP │
│2004-11-07│mhadley│and WSDL document contents. Removed dependency on │
│@ 02:03 │ │WS-Policy. Removed references to WS-Trust and │
│ │ │WS-SecurityPolicy │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│2004-11-02│mhadley│Replaced hardcoded change log with one generated │
│@ 21:45 │ │dynamically from CVS │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│2004-10-28│mhadley│Fixed typo in abstract │
│@ 18:09 │ │ │
├──────────┼───────┼──────────────────────────────────────────────────────────┤
│2004-10-28│mhadley│Initial cut of separating specification into core, soap │
│@ 17:05 │ │and wsdl │
└──────────┴───────┴──────────────────────────────────────────────────────────┘