WS-I

Basic Profile Version 2.0

Working Group Draft

2010-02-16

This version:
http://www.ws-i.org/Profiles/BasicProfile-2.0-2010-02-16.html
Latest version:
http://www.ws-i.org/Profiles/BasicProfile-2.0.html
Editors:
Robert Chumbley , IBM
Jacques Durand , Fujitsu
Gilbert Pilz , Oracle
Tom Rutt , Fujitsu
Administrative contact:
secretary@ws-i.org

Abstract

This document defines the WS-I Basic Profile 2.0, consisting of a set of non-proprietary Web services specifications, along with clarifications, refinements, interpretations and amplifications of those specifications which promote interoperability. It also contains a set of executable test assertions for assessing the conformance to the profile.

Status of this Document

This document is a Working Group Draft; it has been accepted by the Working Group as reflecting the current state of discussions. It is a work in progress, and should not be considered authoritative or final; other documents may supersede this document.

Notice

The material contained herein is not a license, either expressly or impliedly, to any intellectual property owned or controlled by any of the authors or developers of this material or WS-I. The material contained herein is provided on an "AS IS" basis and to the maximum extent permitted by applicable law, this material is provided AS IS AND WITH ALL FAULTS, and the authors and developers of this material and WS-I hereby disclaim all other warranties and conditions, either express, implied or statutory, including, but not limited to, any (if any) implied warranties, duties or conditions of merchantability, of fitness for a particular purpose, of accuracy or completeness of responses, of results, of workmanlike effort, of lack of viruses, and of lack of negligence. ALSO, THERE IS NO WARRANTY OR CONDITION OF TITLE, QUIET ENJOYMENT, QUIET POSSESSION, CORRESPONDENCE TO DESCRIPTION OR NON-INFRINGEMENT WITH REGARD TO THIS MATERIAL.

IN NO EVENT WILL ANY AUTHOR OR DEVELOPER OF THIS MATERIAL OR WS-I BE LIABLE TO ANY OTHER PARTY FOR THE COST OF PROCURING SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF USE, LOSS OF DATA, OR ANY INCIDENTAL, CONSEQUENTIAL, DIRECT, INDIRECT, OR SPECIAL DAMAGES WHETHER UNDER CONTRACT, TORT, WARRANTY, OR OTHERWISE, ARISING IN ANY WAY OUT OF THIS OR ANY OTHER AGREEMENT RELATING TO THIS MATERIAL, WHETHER OR NOT SUCH PARTY HAD ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.

Feedback

The Web Services-Interoperability Organization (WS-I) would like to receive input, suggestions and other feedback ("Feedback") on this work from a wide variety of industry participants to improve its quality over time.

By sending email, or otherwise communicating with WS-I, you (on behalf of yourself if you are an individual, and your company if you are providing Feedback on behalf of the company) will be deemed to have granted to WS-I, the members of WS-I, and other parties that have access to your Feedback, a non-exclusive, non-transferable, worldwide, perpetual, irrevocable, royalty-free license to use, disclose, copy, license, modify, sublicense or otherwise distribute and exploit in any manner whatsoever the Feedback you provide regarding the work. You acknowledge that you have no expectation of confidentiality with respect to any Feedback you provide. You represent and warrant that you have rights to provide this Feedback, and if you are providing Feedback on behalf of a company, you represent and warrant that you have the rights to provide Feedback on behalf of your company. You also acknowledge that WS-I is not required to review, discuss, use, consider or in any way incorporate your Feedback into future versions of its work. If WS-I does incorporate some or all of your Feedback in a future version of the work, it may, but is not obligated to include your name (or, if you are identified as acting on behalf of your company, the name of your company) on a list of contributors to the work. If the foregoing is not acceptable to you and any company on whose behalf you are acting, please do not provide any Feedback.

Feedback on this document should be directed to wsbasic_comment@ws-i.org.


Table of Contents

1. Introduction
1.1. Relationships to Other Profiles
1.2. Guiding Principles
1.3. Test Assertions
1.4. Compatibility with Basic Profile 1.1 and 1.2
1.5. Notational Conventions
1.6. Profile Identification and Versioning
2. Profile Conformance
2.1. Conformance Requirements
2.2. Conformance Targets
2.3. Conformance Scope
2.4. Claiming Conformance
3. Messaging
3.1. Message Serialization
3.1.1. XML Envelope Serialization
3.1.2. Unicode BOMs
3.1.3. XML Declarations
3.1.4. Character Encodings
3.1.5. XOP Encoded Messages
3.2. SOAP Envelopes
3.2.1. SOAP Envelope Structure
3.2.2. SOAP Body Namespace Qualification
3.2.3. Disallowed Constructs
3.2.4. xsi:type Attributes
3.2.5. SOAP 1.2 attributes on SOAP 1.2 elements
3.3. SOAP Processing Model
3.3.1. SOAP Fault Processing
3.4. SOAP Faults
3.4.1. Identifying SOAP Faults
3.5. Use of SOAP in HTTP
3.5.1. HTTP Protocol Binding
3.5.2. Parameters on the Content-Type MIME Header
3.5.3. HTTP Success Status Codes
3.5.4. HTTP Redirect Status Codes
3.5.5. HTTP Cookies
3.5.6. Non-Addressable Consumers and Instances
3.6. Use of URIs in SOAP
3.6.1. Use of SOAP-defined URIs
3.7. WS-Addressing Support
3.7.1. Requiring WS-Addressing SOAP headers
3.7.2. NotUnderstood block in MustUnderstand Fault on WS-Addressing SOAP headers
3.7.3. Use of wsa:Action and WS-Addressing 1.0 - Metadata
3.7.4. Valid Values for action Parameter on the Content-Type MIME header When WS-Addressing is Used
3.7.5. SOAP Defined Faults Action URI
3.7.6. Understanding WS-Addressing SOAP Header Blocks
3.7.7. Ignored or Absent WS-Addressing MAPs
3.7.8. Present and Understood WS-Addressing MAPs
3.7.9. SOAP MustUnderstand or VersionMismatch fault Transmission
3.7.10. Faulting Behavior with Present and Understood WS-Addressing MAPs
3.7.11. [message id] and One-Way Operations
3.7.12. Refusal to Honor WS-Addressing MAPs
3.7.13. Use of Non-Anonymous Response EPRs
3.7.14. Optionality of the wsa:To header
3.7.15. Extending WSDL Endpoints with an EPR
3.7.16. Combining Synchronous and Asynchronous Operations
3.7.17. Conflicting Addressing Policies
4. Service Description
4.1. Required Description
4.2. Document Structure
4.2.1. WSDL Schema Definitions
4.2.2. WSDL and Schema Import
4.2.3. WSDL Import location Attribute Structure
4.2.4. WSDL Import location Attribute Semantics
4.2.5. Placement of WSDL import Elements
4.2.6. XML Version Requirements
4.2.7. XML Namespace Declarations
4.2.8. WSDL and the Unicode BOM
4.2.9. Acceptable WSDL Character Encodings
4.2.10. Namespace Coercion
4.2.11. WSDL documentation Element
4.2.12. WSDL Extensions
4.3. Types
4.3.1. QName References
4.3.2. Schema targetNamespace Structure
4.3.3. soapenc:Array
4.3.4. WSDL and Schema Definition Target Namespaces
4.3.5. Multiple GED Definitions with the same QName
4.3.6. Multiple Type Definitions with the same QName
4.4. Messages
4.4.1. Bindings and Parts
4.4.2. Bindings and Faults
4.4.3. Unbound portType Element Contents
4.4.4. Declaration of part Elements
4.5. Port Types
4.5.1. Ordering of part Elements
4.5.2. Allowed Operations
4.5.3. Distinctive Operations
4.5.4. parameterOrder Attribute Construction
4.5.5. Exclusivity of type and element Attributes
4.6. Bindings
4.6.1. Use of SOAP Binding
4.7. SOAP Binding
4.7.1. Specifying the transport Attribute
4.7.2. HTTP Transport
4.7.3. Consistency of style Attribute
4.7.4. Encodings and the use Attribute
4.7.5. Multiple Bindings for portType Elements
4.7.6. Operation Signatures
4.7.7. Multiple Ports on an Endpoint
4.7.8. Child Element for Document-Literal Bindings
4.7.9. One-Way Operations
4.7.10. Namespaces for wsoap12 Elements
4.7.11. Consistency of portType and binding Elements
4.7.12. SOAP 1.2 Binding Extension Correction
4.7.13. Enumeration of Faults
4.7.14. Type and Name of SOAP Binding Elements
4.7.15. name Attribute on Faults
4.7.16. Omission of the use Attribute
4.7.17. Default for use Attribute
4.7.18. Consistency of Envelopes with Descriptions
4.7.19. Response Wrappers
4.7.20. Part Accessors
4.7.21. Namespaces for Children of Part Accessors
4.7.22. Required Headers
4.7.23. Allowing Undescribed Headers
4.7.24. Ordering Headers
4.7.25. Describing action Parameter on the Content-Type MIME Header
4.7.26. SOAPAction HTTP Header
4.7.27. SOAP Binding Extensions
4.8. Use of @soapActionRequired in WSDL 1.1 SOAP 1.2 Binding
4.9. Use of XML Schema
4.10. WS-Addressing 1.0 - Metadata
5. Service Publication and Discovery
5.1. bindingTemplates
5.2. tModels
6. Security
6.1. Use of HTTPS
Appendix A: Referenced Specifications
Appendix B: Extensibility Points
Appendix C: Normative References
Appendix D: Defined Terms
Appendix E: Acknowledgements

1. Introduction

This document defines the WS-I Basic Profile 2.0 (hereafter, "Profile"), consisting of a set of non-proprietary Web services specifications, along with clarifications, refinements, interpretations and amplifications of those specifications which promote interoperability.

Section 1 introduces the Profile, and explains its relationships to other profiles.

Section 2, "Profile Conformance," explains what it means to be conformant to the Profile.

Each subsequent section addresses a component of the Profile, and consists of two parts; an overview detailing the component specifications and their extensibility points, followed by subsections that address individual parts of the component specifications. Note that there is no relationship between the section numbers in this document and those in the referenced specifications.

1.1 Relationships to Other Profiles

This Profile is derived from the Basic Profile 1.1 by incorporating any errata to date and including those requirements related to the serialization of envelopes and their representation in messages from the Simple SOAP Binding Profile 1.0 .

This Profile is NOT intended to be composed with the Simple SOAP Binding Profile 1.0. The Attachments Profile 1.0 adds support for SOAP with Attachments, and is intended to be used in combination with this Profile.

1.2 Guiding Principles

The Profile was developed according to a set of principles that, together, form the philosophy of the Profile, as it relates to bringing about interoperability. This section documents these guidelines.

No guarantee of interoperability
It is impossible to completely guarantee the interoperability of a particular service. However, the Profile does address the most common problems that implementation experience has revealed to date.
Application semantics
Although communication of application semantics can be facilitated by the technologies that comprise the Profile, assuring the common understanding of those semantics is not addressed by it.
Testability
When possible, the Profile makes statements that are testable. However, requirements do not need to be testable to be included in the Profile. Preferably, testing is achieved in a non-intrusive manner (e.g., by examining artifacts "on the wire").
Strength of requirements
The Profile makes strong requirements (e.g., MUST, MUST NOT) wherever feasible; if there are legitimate cases where such a requirement cannot be met, conditional requirements (e.g., SHOULD, SHOULD NOT) are used. Optional and conditional requirements introduce ambiguity and mismatches between implementations.
Restriction vs. relaxation
When amplifying the requirements of referenced specifications, the Profile may restrict them, but does not relax them (e.g., change a MUST to a MAY).
Multiple mechanisms
If a referenced specification allows multiple mechanisms to be used interchangeably, the Profile selects those that are well-understood, widely implemented and useful. Extraneous or underspecified mechanisms and extensions introduce complexity and therefore reduce interoperability.
Future compatibility
When possible, the Profile aligns its requirements with in-progress revisions to the specifications it references. This aids implementers by enabling a graceful transition, and assures that WS-I does not 'fork' from these efforts. When the Profile cannot address an issue in a specification it references, this information is communicated to the appropriate body to assure its consideration.
Compatibility with deployed services
Backwards compatibility with deployed Web services is not a goal for the Profile, but due consideration is given to it; the Profile does not introduce a change to the requirements of a referenced specification unless doing so addresses specific interoperability issues.
Focus on interoperability
Although there are potentially a number of inconsistencies and design flaws in the referenced specifications, the Profile only addresses those that affect interoperability.
Conformance targets
Where possible, the Profile places requirements on artifacts (e.g., WSDL descriptions, SOAP messages) rather than the producing or consuming software's behaviors or roles. Artifacts are concrete, making them easier to verify and therefore making conformance easier to understand and less error-prone.
Lower-layer interoperability
The Profile speaks to interoperability at the application layer; it assumes that interoperability of lower-layer protocols (e.g., TCP, IP, Ethernet) is adequate and well-understood. Similarly, statements about application-layer substrate protocols (e.g., SSL/TLS, HTTP) are only made when there is an issue affecting Web services specifically; WS-I does not attempt to assure the interoperability of these protocols as a whole. This assures that WS-I's expertise in and focus on Web services standards is used effectively.

1.3 Test Assertions

This profile document contains embedded Test Assertions (TA) that are associated with each normative profile requirement. In the HTML rendering of this document, these test assertions are accessible via a toggle link at the end of each requirement. When clicking on such a link, a table pops up that displays the TA parts. At the end of this table is another toggle link ("help-glossary") that displays an explanation glossary for the TA structure. In other formats of this document, the test assertions are grouped in an appendix not controlled by any link, in order to facilitate the printing of hard copies. The resulting set of test assertions embedded in this document represents a conformance test suite for the profile.

Release notes related to the test material included in this document are available here:

TESTING-RELEASE-NOTES

1.4 Compatibility with Basic Profile 1.1 and 1.2

The Basic Profile 2.0 is the first version of the WS-I Basic Profile that changes the version of SOAP in the profile scope from SOAP 1.1 to the W3C SOAP 1.2 Recommendation. As such, clients, servers and the artifacts that comprise a Basic Profile 1.0, 1.1 or 1.2 conformant application are inherently incompatible with an application that is conformant with the Basic Profile 2.0. However, in general, the Basic Profile WG members have tried to preserve in the Basic Profile 2.0 as much consistency with the guidance and constraints of the Basic Profile 1.0, 1.1 and 1.2 as possible. This has been in part facilitated by the fact that the WG tried to remain consistent in the guidance and constraints of the original Basic Profile with the decisions that were being made in the context of the W3C XML Protocols WG as they were concurrently working on the SOAP 1.2 specificatons. For the most part, issues that were resolved in the context of the development of the Basic Profile 1.0, 1.1 and 1.2 were not revisited.

1.5 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 RFC2119.

Normative statements of requirements in the Profile (i.e., those impacting conformance, as outlined in "Conformance Requirements") are presented in the following manner:

RnnnnStatement text here.

where "nnnn" is replaced by a number that is unique among the requirements in the Profile, thereby forming a unique requirement identifier.

Requirements can be considered to be namespace qualified, in such a way as to be compatible with QNames from Namespaces in XML. If there is no explicit namespace prefix on a requirement's identifier (e.g., "R9999" as opposed to "bp10:R9999"), it should be interpreted as being in the namespace identified for this Profile.

Extensibility points in underlying specifications (see "Conformance Scope") are presented in a similar manner:

EnnnnExtensibility Point Name - Description

where "nnnn" is replaced by a number that is unique among the extensibility points in the Profile. As with requirement statements, extensibility statements can be considered namespace-qualified.

This Profile supports multiple conformance targets. Requirements or sections specific to the use of a particular conformance target are annotated in the following manner: TARGET.

This specification uses a number of namespace prefixes throughout; their associated URIs are listed below. Note that the choice of any namespace prefix is arbitrary and not semantically significant.

1.6 Profile Identification and Versioning

This document is identified by a name (in this case, Basic Profile) and a version number (here, 2.0). Together, they identify a particular profile instance.

Version numbers are composed of a major and minor portion, in the form "major.minor". They can be used to determine the precedence of a profile instance; a higher version number (considering both the major and minor components) indicates that an instance is more recent, and therefore supersedes earlier instances.

Instances of profiles with the same name (e.g., "Example Profile 1.1" and "Example Profile 5.0") address interoperability problems in the same general scope (although some developments may require the exact scope of a profile to change between instances).

One can also use this information to determine whether two instances of a profile are backwards-compatible; that is, whether one can assume that conformance to an earlier profile instance implies conformance to a later one. Profile instances with the same name and major version number (e.g., "Example Profile 1.0" and "Example Profile 1.1") MAY be considered compatible. Note that this does not imply anything about compatibility in the other direction; that is, one cannot assume that conformance with a later profile instance implies conformance to an earlier one.

2 Profile Conformance

Conformance to the Profile is defined by adherence to the set of requirements defined for a specific target, within the scope of the Profile. This section explains these terms and describes how conformance is defined and used.

2.1 Conformance Requirements

Requirements state the criteria for conformance to the Profile. They typically refer to an existing specification and embody refinements, amplifications, interpretations and clarifications to it in order to improve interoperability. All requirements in the Profile are considered normative, and those in the specifications it references that are in-scope (see "Conformance Scope") should likewise be considered normative. When requirements in the Profile and its referenced specifications contradict each other, the Profile's requirements take precedence for purposes of Profile conformance.

Requirement levels, using RFC2119 language (e.g., MUST, MAY, SHOULD) indicate the nature of the requirement and its impact on conformance. Each requirement is individually identified (e.g., R9999) for convenience.

For example;

R9999 Any WIDGET SHOULD be round in shape.

This requirement is identified by "R9999", applies to the target WIDGET (see below), and places a conditional requirement upon widgets.

Each requirement statement contains exactly one requirement level keyword (e.g., "MUST") and one conformance target keyword (e.g., "MESSAGE"). The conformance target keyword appears in bold text (e.g. "MESSAGE"). Other conformance targets appearing in non-bold text are being used strictly for their definition and NOT as a conformance target. Additional text may be included to illuminate a requirement or group of requirements (e.g., rationale and examples); however, prose surrounding requirement statements must not be considered in determining conformance.

Definitions of terms in the Profile are considered authoritative for the purposes of determining conformance.

None of the requirements in the Profile, regardless of their conformance level, should be interpreted as limiting the ability of an otherwise conforming implementation to apply security countermeasures in response to a real or perceived threat (e.g., a denial of service attack).

2.2 Conformance Targets

Conformance targets identify what artifacts (e.g., SOAP message, WSDL description, UDDI registry data) or parties (e.g., SOAP processor, end user) requirements apply to.

This allows for the definition of conformance in different contexts, to assure unambiguous interpretation of the applicability of requirements, and to allow conformance testing of artifacts (e.g., SOAP messages and WSDL descriptions) and the behavior of various parties to a Web service (e.g., clients and service instances).

Requirements' conformance targets are physical artifacts wherever possible, to simplify testing and avoid ambiguity.

The following conformance targets are used in the Profile:

2.3 Conformance Scope

The scope of the Profile delineates the technologies that it addresses; in other words, the Profile only attempts to improve interoperability within its own scope. Generally, the Profile's scope is bounded by the specifications referenced by it.

The Profile's scope is further refined by extensibility points. Referenced specifications often provide extension mechanisms and unspecified or open-ended configuration parameters; when identified in the Profile as an extensibility point, such a mechanism or parameter is outside the scope of the Profile, and its use or non-use is not relevant to conformance.

Note that the Profile may still place requirements on the use of an extensibility point. Also, specific uses of extensibility points may be further restricted by other profiles, to improve interoperability when used in conjunction with the Profile.

Because the use of extensibility points may impair interoperability, their use should be negotiated or documented in some fashion by the parties to a Web service; for example, this could take the form of an out-of-band agreement.

The Profile's scope is defined by the referenced specifications in Appendix A, as refined by the extensibility points in Appendix B.

2.4 Claiming Conformance

Claims of conformance to the Profile can be made using the following mechanisms, as described in Conformance Claim Attachment Mechanisms, when the applicable Profile requirements associated with the listed targets have been met:

Claims of conformance for the Basic Profile 2.0 encompass the transport-independent and HTTP-specific requirements. Claims are separated into two disjoint parts and an aggregated claim for the complete Basic Profile: "CORE", "HTTP-TRANSPORT", and "COMPLETE". The Basic Profile 2.0 conformance claim URI(s) are:

The union of the requirements tagged as "HTTP-TRANSPORT" and "CORE" requirements comprise "BP 2.0 Complete".

3. Messaging

This section of the Profile incorporates the following specifications by reference, and defines extensibility points within them:

3.1 Message Serialization

The profile is intended to compose with mechanisms currently under development to describe whether messages are encoded as SIMPLE_SOAP_MESSAGEs or XOP_ENCODED_MESSAGEs. As such it does not mandate that both of those encodings be supported for any given operation. Indeed, neither of these encodings need be supported if an alternate encoding such as that described in the Attachments Profile 1.0 is used.

SOAP 1.2 defines an XML structure for serializing messages, the envelope. The Profile places the following constraints on the use and serialization of the soap12:Envelope element and its content:

This Profile allows for the use of protocol bindings other than HTTP. Section 2.2 identifies the use of Simple SOAP and XOP encoded messages using HTTP. Section 3.1 identifies how encoding is handled for HTTP only. RFC 2616 and RFC 3023 provide guidance for HTTP. If another transport protocol is used, the responsibility for defining how to handle transport-specific features (e.g. content encoding) falls to the specification of the binding of SOAP to that transport protocol.

This section of the Profile incorporates the following specifications by reference:

3.1.1 XML Envelope Serialization

R9701 An ENVELOPE MUST be serialized as XML 1.0. CORE TESTABLE BP1019

3.1.2 Unicode BOMs

XML 1.0 allows UTF-8 encoding to include a BOM; therefore, receivers of envelopes must be prepared to accept them. The BOM is mandatory for XML encoded as UTF-16.

R4001 A RECEIVER MUST accept envelopes that include the Unicode Byte Order Mark (BOM). CORE NOT_TESTABLE

3.1.3 XML Declarations

Presence or absence of an XML declaration does not affect interoperability. Certain implementations might always precede their XML serialization with the XML declaration.

R1010 A RECEIVER MUST accept messages with envelopes that contain an XML Declaration. CORE TESTABLE BP1015

3.1.4 Character Encodings

The Profile requires XML processors to support the "UTF-8" and "UTF-16" character encodings, in order to aid interoperability.

To improve interoperabilitry, the "charset" parameter of Content-Type HTTP header field must be used to determine the correct character encoding of the message.

As this Profile allows the use of protocol bindings other than HTTP, the transport is responsible for defining how encoding is handled as specified in Section 2.2 for Simple SOAP and XOP encoded messages using HTTP. This applies to this section and Section 3.1.5 .

R1012 An ENVELOPE MUST be serialized using either UTF-8 or UTF-16 character encoding. CORE TESTABLE BP1018

R1018 A SIMPLE_SOAP_MESSAGE MUST indicate the correct character encoding, using the "charset" parameter. CORE TESTABLE BP1018

R1019 A RECEIVER MUST ignore the encoding pseudo-attribute of the envelope's XML declaration. CORE NOT_TESTABLE

3.1.5 XOP Encoded Messages

There are implementations that are apparently encoding the action parameter as a separate parameter of the enclosing MIME multipart/related entity body's Content-Type header. The multipart/related media type specification does not include an action parameter, though it does permit extensibility. Thus, the action parameter on the multipart/related Content-Type header has no defined semantic. The correct encoding is to include the action parameter inside the start-info parameter of the enclosing MIME multipart/related entity body as well as inside the type parameter of the root part.

See Section 3.1.4 for conformance criteria when using HTTP.

R1020 A XOP_ENCODED_MESSAGE MUST include the start-info parameter in the Content-Type header of the enclosing multipart/related MIME entity body. CORE TESTABLE BP1020

R1021 A XOP_ENCODED_MESSAGE SHOULD include the full value of the type parameter from the root entity body part inside the start-info parameter of the enclosing multipart/related MIME entity body part's Content-Type header. CORE TESTABLE BP1021

R1022 A RECEIVER MUST accept a XOP encoded message that has the action parameter, associated with the SOAP message, encoded inside the start-info parameter on the Content-Type header of the enclosing multipart/related MIME entity body. CORE NOT_TESTABLE

R1023 A RECEIVER MAY accept a XOP encoded message that has the action parameter, associated with the SOAP message, encoded as a separate parameter on the Content-Type header of the enclosing multipart/related MIME entity body. CORE NOT_TESTABLE

For example,

INCORRECT:

MIME-Version: 1.0
Content-Type: Multipart/Related;boundary=MIME_boundary;
  type="application/xop+xml";
  start="<mymessage.xml@example.org>";
  start-info="application/soap+xml";
  action="ProcessData"

--MIME_boundary
Content-Type: application/xop+xml;
  charset=UTF-8;
  type="application/soap+xml; action=\"ProcessData\""
Content-Transfer-Encoding: 8bit
Content-ID: <mymessage.xml@example.org>
...

CORRECT:

MIME-Version: 1.0
Content-Type: Multipart/Related;boundary=MIME_boundary;
  type="application/xop+xml";
  start="<mymessage.xml@example.org>";
  start-info="application/soap+xml; action=\"ProcessData\""
Content-Description: A SOAP message with my pic and sig in it

--MIME_boundary
Content-Type: application/xop+xml;
  charset=UTF-8;
  type="application/soap+xml; action=\"ProcessData\""
Content-Transfer-Encoding: 8bit
Content-ID: <mymessage.xml@example.org>
...

3.2 SOAP Envelopes

SOAP 1.2, Section 5 , defines a structure for composing messages, the "SOAP Envelope". The Profile mandates the use of that structure, and places the following constraints on its use:

3.2.1 SOAP Envelope Structure

R9980 An ENVELOPE MUST conform to the structure specified in SOAP Version 1.2 Part 1, Section 5, "SOAP Envelope" (subject to amendment by the Profile). CORE TESTABLE BP1600

R9981 An ENVELOPE MUST have exactly zero or one child elements of the soap12:Body element. CORE TESTABLE BP1881

While the combination of R2201 and R2210 (below) clearly imply that there may be at most one child element of the soap12:Body , there is no explicit requirement in the Profile that articulates this constraint, leading to some confusion.

3.2.2 SOAP Body Namespace Qualification

The use of unqualified element names may cause naming conflicts, therefore qualified names must be used for the children of soap12:Body .

R1014 The children of the soap12:Body element in an ENVELOPE MUST be namespace qualified. CORE TESTABLE BP1202

3.2.3 Disallowed Constructs

XML DTDs and PIs may introduce security vulnerabilities, processing overhead and semantic ambiguity when used in envelopes. As a result, certain XML constructs are disallowed by section 5 of SOAP 1.2.

Although published errata NE05 (see http://www.w3.org/XML/xml-names-19990114-errata ) allows the namespace declaration xmlns:xml="http://www.w3.org/XML/1998/namespace" to appear, some older processors considered such a declaration to be an error. These requirements ensure that conformant artifacts have the broadest interoperability possible.

R1008 An ENVELOPE MUST NOT contain a Document Type Declaration. CORE TESTABLE BP1007

R1009 An ENVELOPE MUST NOT contain Processing Instructions. CORE TESTABLE BP1208

R1033 An ENVELOPE SHOULD NOT contain the namespace declaration xmlns:xml="http://www.w3.org/XML/1998/namespace". CORE TESTABLE BP1033

3.2.4 xsi:type Attributes

In many cases, senders and receivers will share some form of type information related to the envelopes being exchanged.

R1017 A RECEIVER MUST NOT mandate the use of the xsi:type attribute in envelopes except as required in order to indicate a derived type (see XML Schema Part 1: Structures, Section 2.6.1). CORE NOT_TESTABLE

3.2.5 SOAP 1.2 attributes on SOAP 1.2 elements

R1032 The soap12:Envelope, soap12:Header, and soap12:Body elements in an ENVELOPE MUST NOT have attributes in the namespace "http://www.w3.org/2003/05/soap-envelope". CORE TESTABLE BP1032

3.3 SOAP Processing Model

SOAP 1.2, Section 2 defines a model for the processing of envelopes. In particular, it defines rules for the processing of header blocks and the envelope body. It also defines rules related to generation of faults. The Profile places the following constraints on the processing model:

3.3.1 SOAP Fault Processing

When a fault is generated, no further processing should be performed. In request-response exchanges, a fault message will be transmitted to the sender of the request, and some application level error will be flagged to the user.

Both SOAP and this Profile use the term 'generate' to denote the creation of a SOAP Fault. It is important to realize that generation of a Fault is distinct from its transmission, which in some cases is not required.

R1029 Where the normal outcome of processing a SOAP envelope would have resulted in the transmission of a SOAP response, but rather a fault is generated instead, the RECEIVER MUST NOT transmit the non-faulting response. CORE NOT_TESTABLE

Note that there may be valid reasons (such as security considerations) why a fault might not be transmitted.

3.4 SOAP Faults

3.4.1 Identifying SOAP Faults

Some consumer implementations erroneously use only the HTTP status code to determine the presence of a Fault. Because there are situations where the Web infrastructure changes the HTTP status code, and for general reliability, the Profile requires that they examine the envelope. A Fault is an envelope that has a single child element of the soap12:Body element, that element being the soap12:Fault element.

R1107 A RECEIVER MUST interpret a SOAP message as a Fault when the soap12:Body of the message has a single soap12:Fault child. CORE NOT_TESTABLE

3.5 Use of SOAP in HTTP

While SOAP itself is not transport specific, this Profile focuses on its use with HTTP and makes no requirements on the use of any other transport. Other profiles might be developed to focus on the particulars of other transports, but that is out of scope for this Profile. With respect to compliance to this Profile, any requirement that mentions the HTTP transport applies only when HTTP is being used. Any requirement that is not specific to HTTP (i.e. does not mention HTTP specifically) applies toward conformance regardless of the transport mechanism being used.

Section 7 of SOAP 1.2 Part 2 defines a single protocol binding, for HTTP/1.1 . The Profile makes use of that binding, and places the following constraints on its use:

For this section, the conformance criteria for the use of HTTP as a transport protocol are specified in Section 2.3 .

3.5.1 HTTP Protocol Binding

Several versions of HTTP are defined. HTTP/1.1 has performance advantages, and is more clearly specified than HTTP/1.0.

R1141 When HTTP is used as the transport, a MESSAGE MUST be sent using either HTTP/1.1 or HTTP/1.0. HTTP-TRANSPORT TESTABLE BP1002

R1140 When HTTP is used as the transport, a MESSAGE SHOULD be sent using HTTP/1.1. HTTP-TRANSPORT TESTABLE BP1001

Note that support for HTTP/1.0 is implied in HTTP/1.1, and that intermediaries may change the version of a message; for more information about HTTP versioning, see RFC2145, "Use and Interpretation of HTTP Version Numbers."

3.5.2 Parameters on the Content-Type MIME Header

Testing has demonstrated that requiring parameters on the Content-Type MIME header field-value to be quoted increases interoperability of implementations. Even though HTTP allows unquoted header field-values, some SOAP implementations require that they be quoted.

R1109 If present, the values of the following parameters - type, start-info, action, and boundary - on the Content-Type MIME header field-value in a request MESSAGE MUST be a quoted string. HTTP-TRANSPORT TESTABLE BP1006

R1119 A RECEIVER MAY respond with a fault if the applicable parameters on the Content-Type MIME header field-value in a message are not quoted. HTTP-TRANSPORT NOT_TESTED

R1127 A RECEIVER MUST NOT rely on the value of the action parameter on the Content-Type MIME header field-value to correctly process the message. HTTP-TRANSPORT NOT_TESTABLE

3.5.3 HTTP Success Status Codes

HTTP uses the 2xx series of status codes to communicate success. In particular, 200 is the default for successful messages, but 202 can be used to indicate that a message has been submitted for processing. Additionally, other 2xx status codes may be appropriate, depending on the nature of the HTTP interaction.

R1124 An INSTANCE MUST use a 2xx HTTP status code on a response message that indicates the successful outcome of a HTTP Request. HTTP-TRANSPORT NOT_TESTABLE

R1111 An INSTANCE SHOULD use a "200 OK" HTTP status code on a response message that contains an envelope that is not a fault. HTTP-TRANSPORT TESTABLE BP1100

R1112 An INSTANCE SHOULD use either a "200 OK" or "202 Accepted" HTTP status code for a response message that does not contain a SOAP envelope but indicates the successful outcome of a HTTP Request. HTTP-TRANSPORT TESTABLE BP1101

Despite the fact that the HTTP 1.1 assigns different meanings to response status codes "200" and "202", in the context of the Profile they should be considered equivalent by the initiator of the request. The Profile accepts both status codes because some SOAP implementations have little control over the HTTP protocol implementation and cannot control which of these response status codes is sent.

3.5.4 HTTP Redirect Status Codes

There are interoperability problems with using many of the HTTP redirect status codes, generally surrounding whether to use the original method, or GET. The Profile mandates "307 Temporary Redirect", which has the semantic of redirection with the same HTTP method, as the correct status code for redirection. For more information, see the 3xx status code descriptions in RFC2616.

R1130 An INSTANCE MUST use the "307 Temporary Redirect" HTTP status code when redirecting a request to a different endpoint. HTTP-TRANSPORT NOT_TESTABLE

R1131 A CONSUMER MAY automatically redirect a request when it encounters a "307 Temporary Redirect" HTTP status code in a response. HTTP-TRANSPORT NOT_TESTED

RFC2616 notes that user-agents should not automatically redirect requests; however, this requirement was aimed at browsers, not automated processes (which many Web services will be). Therefore, the Profile allows, but does not require, consumers to automatically follow redirections.

3.5.5 HTTP Cookies

The HTTP State Management Mechanism ("Cookies") allows the creation of stateful sessions between Web browsers and servers. Being designed for hypertext browsing, Cookies do not have well-defined semantics for Web services, and, because they are external to the envelope, are not accommodated by either SOAP 1.2 or WSDL 1.1. However, there are situations where it may be necessary to use Cookies; e.g., for load balancing between servers, or for integration with legacy systems that use Cookies. For these reasons, the Profile limits the ways in which Cookies can be used, without completely disallowing them.

R1120 An INSTANCE MAY use the HTTP state mechanism ("Cookies"). HTTP-TRANSPORT NOT_TESTED

R1122 An INSTANCE using Cookies SHOULD conform to RFC2965. HTTP-TRANSPORT NOT_TESTED

R1121 An INSTANCE SHOULD NOT require consumer support for Cookies in order to function correctly. HTTP-TRANSPORT NOT_TESTED

R1123 The value of the cookie MUST be considered to be opaque by the CONSUMER. HTTP-TRANSPORT NOT_TESTABLE

The Profile recommends that cookies not be required by instances for proper operation; they should be a hint, to be used for optimization, without materially affecting the execution of the Web service. However, they may be required in legacy integration and other exceptional use cases, so requiring them does not make an instance non-conformant. While Cookies thus may have meaning to the instance, they should not be used as an out-of-bound data channel between the instance and the consumer. Therefore, interpretation of Cookies is not allowed at all by the consumer - it is required to treat them as opaque (i.e., have no meaning to the consumer).

3.5.6 Non-Addressable Consumers and Instances

Definition: non-addressable

A CONSUMER or INSTANCE is deemed "non-addressable" when, for whatever reason, it is either unwilling or unable to provide a network endpoint that is capable of accepting connections. This means that the CONSUMER or INSTANCE cannot service incoming HTTP connections and can only transmit HTTP Request messages and receive HTTP Response messages.

Non-addressable CONSUMERs and INSTANCEs, by their nature, cannot service incoming HTTP connections. Therefore any ENVELOPEs that they receive, either as requests (in the case of INSTANCEs) or responses (in the case of CONSUMERs), MUST, when HTTP is used, be carried in the entity-body of an HTTP Request message.

R1201 When a CONSUMER is non-addressable, a SOAP ENVELOPE, that is described by the input message of a WSDL operation supported by an INSTANCE, MUST be bound to a HTTP Request message. HTTP-TRANSPORT TESTABLE BP1125a BP1125b

R1202 When a CONSUMER is non-addressable, a SOAP ENVELOPE, that is described by the output message of a WSDL operation supported by an INSTANCE, MUST be bound to a HTTP Response message. HTTP-TRANSPORT TESTABLE BP1126a BP1126b

R1203 When an INSTANCE is non-addressable, a SOAP ENVELOPE, that is described by the input message of a WSDL operation supported by the INSTANCE, MUST be bound to a HTTP Response message. HTTP-TRANSPORT TESTABLE

R1204 When an INSTANCE is non-addressable, a SOAP ENVELOPE, that is described by the output message of a WSDL operation supported by the INSTANCE, MUST be bound to a HTTP Request message. HTTP-TRANSPORT TESTABLE

Note that INSTANCEs can poll for requests from CONSUMERs using mechanisms such as those described in WS-MakeConnection .

3.6 Use of URIs in SOAP

This section of the Profile incorporates the following specifications by reference:

SOAP 1.2, Section 6 describes the use URIs as identifiers. For example, the role attribute value is a URI that identifies the SOAP node(s) to which a particular header block is targeted. To ensure interoperability it is important that SENDERs and RECEIVERs share a common understanding of how such URI values will be compared. The Profile places the following constraints on the use of such URI values:

3.6.1 Use of SOAP-defined URIs

A SOAP 1.2 defined URI, such as the role value "http://www.w3.org/2003/05/soap-envelope/role/next", is treated as follows:

R1160 A RECEIVER, for the purposes of comparison of URI values of information items defined by the SOAP 1.2 specification, MUST treat the computed absolute URI values as simple strings as defined in RFC3986 (see RFC3986, Section 6.2.1). CORE NOT_TESTABLE

3.7 WS-Addressing Support

This section of the Profile incorporates the following specifications by reference:

WS-Addressing is a part of core Web services infrastructure. To facilitate interoperability and to provide a common baseline, this profile requires compliant clients and services to provide support for WS-Addressing Core, WS-Addressing SOAP Binding and WS-Addressing Metadata, as modified by this Profile.

Support for WS-Addressing by a specific "service" is optional. However, a service may require the use of WS-Addressing, in which case, for successful interaction with that service, a client will need to support it.

Note that two BP compliant web services instances may both support the use of WS- Addressing yet fail to agree on a common set of features necessary to interact with one another. For example, a RECEIVER may require the use of non-anonymous response EPRs (and advertise this via the wsam:NonAnonymousResponses nested policy assertion) yet a SENDER, for various reasons (e.g. the presence of NATs or firewalls), may only support the use of anonymous response EPRs.

3.7.1 Requiring WS-Addressing SOAP headers

R1040 If an endpoint requires use of WS-Addressing by use of a wsam:Addressing policy assertion, an ENVELOPE sent by a SENDER MUST carry all required WS-Addressing SOAP headers. CORE NOT_TESTED

3.7.2 NotUnderstood block in MustUnderstand Fault on WS-Addressing SOAP headers

R1041 An ENVELOPE that is a MustUnderstand SOAP fault, sent from an endpoint that has a policy alternative containing the wsam:Addressing assertion attached to its WSDL endpoint subject, MUST NOT contain a NotUnderstood SOAP header block with the qname attribute value that identifies a WS-Addressing defined SOAP header block. CORE NOT_TESTED

3.7.3 Use of wsa:Action and WS-Addressing 1.0 - Metadata

WS-Addressing 1.0 - Metadata, Section 5.1 defines additional constraints on the cardinality of WS-Adressing Message Addressing Properties defined in WS-Addressing 1.0 - Core. These constraints are defined for every message involved in WSDL 1.1 transmission primitives. The Profile requires conformance to this section when WS-Addressing is used in conjunction with a WSDL 1.1 description.

R1142 An ENVELOPE that includes a wsa:Action SOAP header block and which is described using a WSDL 1.1 description MUST conform to WS-Addressing 1.0 - Metadata, Section 5.1. CORE TESTABLE BP1142a BP1142b BP1142c BP1143a BP1143b BP1143c

3.7.4 Valid Values for action Parameter on the Content-Type MIME header When WS-Addressing is Used

There could be some confusion with regards to the range of valid values for the action parameter on the Content-Type MIME header when WS-Addressing is used.

When composed with WS-Addressing, the value of the action parameter, if present, is limited to the absolute URI that matches the value specified for wsa:Action . The action parameter is optional and is therefore not required to be present on the header. This is useful, for example, when the value of wsa:Action is sensitive and is therefore encrypted.

R1144 When the wsa:Action MAP is present in an envelope, the value of the action parameter, if present, on the Content-Type MIME header of the MESSAGE MUST be an absolute URI that has the same value as the value of the wsa:Action MAP. CORE TESTABLE BP1144

3.7.5 SOAP Defined Faults Action URI

WS-Addressing provides the URI http://www.w3.org/2005/08/addressing/soap/fault for "SOAP defined faults". However, it only recommends, rather than mandates its use for the SOAP 1.2 defined MustUnderstand and VersionMismatch faults. This Profile mandates the use of the WS-Addressing defined wsa:Action value for SOAP 1.2 defined MustUnderstand and VersionMismatch faults, for interoperability.

R1035 An ENVELOPE MUST use the http://www.w3.org/2005/08/addressing/soap/fault URI as the value for the wsa:Action element, when present, for either of the SOAP 1.2 defined VersionMismatch and MustUnderstand faults. CORE TESTABLE BP1035

3.7.6 Understanding WS-Addressing SOAP Header Blocks

WS-Addressing 1.0 - SOAP Binding defines multiple SOAP header blocks (wsa:To, wsa:From, wsa:ReplyTo, wsa:FaultTo, wsa:Action, wsa:MessageID, and wsa:RelatesTo). These SOAP header blocks are part of the same module. A SOAP node that conforms to the Profile understands and honors all of these SOAP header blocks (when it understands WS-Addressing) or none at all (when it does not understand WS-Addressing).

R1143 When a message contains multiple WS-Addressing SOAP header blocks with at least one of those header blocks containing a soap12:mustUnderstand='1' attribute, then a RECEIVER MUST honor all the WS-Addressing SOAP header blocks or none of them. CORE NOT_TESTABLE

3.7.7 Ignored or Absent WS-Addressing MAPs

When WS-Addressing MAPs are present in a SOAP envelope, but do not contain a soap12:mustUnderstand="1" attribute, a RECEIVER may choose to ignore these SOAP headers (per R1143 ). Consistent with R1036 , valid reasons may exist why (not where) faults are not transmitted.

R1145 If a SOAP envelope does not contain any WS-Addressing MAPs, or contains WS-Addressing MAPs that do not include any soap12:mustUnderstand="1" attributes and the RECEIVER chooses to ignore them, then any response (normal or fault) SHOULD be transmitted. If it is transmitted then it is transmitted on the HTTP Response message (if available). HTTP-TRANSPORT NOT_TESTED

3.7.8 Present and Understood WS-Addressing MAPs

When any WS-Addressing MAPs are present in a SOAP envelope (where soap12:mustUnderstand="1" attributes exist or the header contents are understood), any non-faulting response will be transmitted to the [reply endpoint] MAP. Should a fault be generated, it replaces the non-faulting response.

R1146 A RECEIVER MUST transmit non-faulting responses to the endpoint referred to by the value of the [reply endpoint] MAP or generate a fault instead (per R1029). CORE TESTABLE BP1146

SOAP 1.2 allows a RECEIVER to ignore headers that it does not understand. This behavior is particularly relevant for WS-Addressing headers that affect message processing and routing. As an example, take the following message sent to a SOAP node that does not understand the "http://www.w3.org/2005/08/addressing" namespace:

<soap12:Envelope xmlns:soap12="http://www.w3.org/2003/05/soap-envelope"
                 xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <soap12:Header>
    <wsa:MessageID>uuid:8B82EA41-1485-13A6-5631527DC83F4168</wsa:MessageID>
    <wsa:Action>http://www.wstf.org/docs/scenarios/sc002/Echo</wsa:Action>
    <wsa:ReplyTo>
      <wsa:Address>http://server.foobie.com/NotifyEcho/asynchResp</wsa:Address>
    </wsa:ReplyTo>
    . . .
  </soap12:Header>
  <soap12:Body>
    . . .
  </soap12:Body>
</soap12:Envelope>

The SENDER expects the response to be sent "server.foobie.com". Yet, because it does not recognize the WS-Addressing 1.0 namespace, the RECEIVER will ignore the WS-Addressing headers as if WS-Addressing weren't engaged; consequently the SOAP response will be sent in the entity-body of the HTTP Response and may be missed by the SENDER.

Another example is where a message with an empty SOAP Body carries the semantic intent in its wsa:Action header.

In situations where the ability of the receiving node to understand WS-Addressing 1.0 headers is in doubt and the correct processing of the WS-Addressing is semantically significant (such as the two examples given), the SENDER is encouraged to add the soap12:mustUnderstand attribute with a value of "1" to the wsa:Action header. This prompts the RECEIVER to generate a MustUnderstand fault in cases where the WS-Addressing headers are not understood.

3.7.9 SOAP MustUnderstand or VersionMismatch fault Transmission

SOAP MustUnderstand and VersionMismatch faults are detected irrespective of the use of WS-Addressing MAPs. There may be valid reasons why (not where) faults are transmitted, e.g. security concerns or the HTTP Response connection is no longer available. In these cases the SENDER will not receive any SOAP envelope response.

R1036 Regardless of whether the wsa:ReplyTo or wsa:FaultTo SOAP headers appear in the incoming message, a RECEIVER that receives a SOAP envelope that generates either a SOAP MustUnderstand or VersionMismatch fault SHOULD transmit either fault. If it is transmitted, such a fault is transmitted on the HTTP Response message (if available). HTTP-TRANSPORT NOT_TESTED

3.7.10 Faulting Behavior with Present and Understood WS-Addressing MAPs

When WS-Addressing MAPs are present in a SOAP envelope (where soap12:mustUnderstand="1" attributes exist or the header contents are understood), should a fault be generated, it will be transmitted to the [fault endpoint] MAP. WS-Addressing specifies expected behavior should the [fault endpoint] be absent.

R1147 If a fault is generated, the RECEIVER SHOULD transmit the fault (per R1029). CORE NOT_TESTED

R1161 Other than those faults specified in R1036, faults in R1147 SHOULD be transmitted by the RECEIVER as specified in WS-Addressing 1.0 - Core, Section 3.4. CORE TESTABLE

R1162 When the [fault endpoint] MAP exists, the RECEIVER MUST NOT transmit faults to the endpoint referred to by the value of the [reply endpoint] MAP. CORE TESTABLE

R1148 If an error occurs when transmitting the fault in R1147, a RECEIVER MAY choose to send a fault related to this transmission error on the HTTP Response (if available). HTTP-TRANSPORT NOT_TESTED

Note: To avoid a recursive situation, if a fault is generated while trying to use the [reply endpoint] MAP (R1146 ) and the [fault endpoint] MAP is absent, R1147 does not apply.

3.7.11 [message id] and One-Way Operations

When sending a one-way message the SENDER could choose to ignore any possible response - for example, a fault. However, if the SENDER is interested in receiving those messages, the SENDER will need to include a [message id] property in the one-way message to ensure that the response can be successfully transmitted (see WS-Addressing 1.0 - Core, Section 3.4 ).

R1163 When applying the processing rules defined by WS-Addressing 1.0 - Core, Section 3.4, if a related message lacks a [message id] property, the RECEIVER MUST generate a wsa:MessageAddressingHeaderRequired fault. CORE TESTABLE

While the RECEIVER is under no obligation to transmit faults, including a [message id] property will provide the RECEIVER with sufficient information to generate a response if needed.

3.7.12 Refusal to Honor WS-Addressing MAPs

There may be many reasons (e.g. security, unsupported wsa:Address values, ...) why a RECEIVER does not honor any WS-Addressing MAPs. In these cases and irrespective of where the condition occurs, when any WS-Addressing MAPs are present in a SOAP envelope (where soap12:mustUnderstand=1 attributes exist or the header contents are understood), the RECEIVER must generate a fault.

R1149 If any WS-Addressing MAPs are not honored, the RECEIVER MUST generate a fault. CORE NOT_TESTABLE

3.7.13 Use of Non-Anonymous Response EPRs

The WS-Addressing [destination] URI of an outgoing message influences where this message will be sent. In the case of the outgoing response (normal or fault), if this URI is a non-anonymous URI then this message will be sent over a separate HTTP connection from one used to carry the request message.

R1152 If an INSTANCE attempts to send a message to a non-anonymous [destination] URI then the message MUST be transmitted in the entity-body of an HTTP Request. CORE TESTABLE BP1152a BP1152b BP1152c

3.7.14 Optionality of the wsa:To header

WS-Addressing 1.0 - Core and WS-Addressing 1.0 - Metadata are unclear about whether and when the wsa:To header element is required in a SOAP message. This Profile makes the following, clarifying requirement.

R1153 Except in cases in which a RECEIVER exposes a WSDL description and its endpoint includes a wsdl:port that has been extended with a wsa:EndpointReference, a RECEIVER MUST NOT fault a SOAP request message due to the absence of the wsa:To header. CORE TESTABLE BP1153a BP1153b

Although the wsa:To header is optional, as a matter of best practice implementations are encouraged to include this header (with a non-anonymous value) as its presence provides a greater degree of flexibility in handling certain situations; for example, when moving a service endpoint from one URI to another.

As per WS-Addressing 1.0 - Core, the [destination] message addressing property of a request message without a wsa:To header is "http://www.w3.org/2005/08/addressing/anonymous". Note that none of the WS-Addressing 1.0 specifications describes the semantics of sending a SOAP request message, over HTTP, either without a wsa:To header or with a wsa:To header with the value of "http://www.w3.org/2005/08/addressing/anonymous". To clarify, such a request is considered to be addressed to "the entity listening at the URI of the HTTP Request that contains this message". Sent over a connection to http://www.example.org, the following three example messages are consistent:

For example,

CORRECT:

POST /NotifyEcho/soap12service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap12:Envelope ...>
 <soap12:Header>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap12:Header>
 <soap12:Body>
   ...
 </soap12:Body>
</soap12:Envelope>

CORRECT:

POST /NotifyEcho/soap12service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap12:Envelope ...>
 <soap12:Header>
    <wsa:To>http://www.w3.org/2005/08/addressing/anonymous</wsa:To>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap12:Header>
 <soap12:Body>
   ...
 </soap12:Body>
</soap12:Envelope>

CORRECT:

POST /NotifyEcho/soap12service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap12:Envelope ...>
 <soap12:Header>
    <wsa:To>http://www.example.org/NotifyEcho/soap12service</wsa:To>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap12:Header>
 <soap12:Body>
   ...
 </soap12:Body>
</soap12:Envelope>

3.7.15 Extending WSDL Endpoints with an EPR

WS-Addressing 1.0 - Metadata is unclear about the relationship between the elements of a WSDL 1.1 description of an endpoint and the values of the addressing properties of a message sent to that endpoint. In particular, the value of the [destination] message addressing property needs to be clarified in order to insure interoperability between SENDER and RECEIVER. There are two cases to consider. The first case is where the wsdl:port has been extended with a wsa:EndpointReference as described by Section 4.1 of WS-Addressing 1.0 - Metadata. In this case the following requirement applies:

R1154 When sending a request message to an endpoint which is specified by a WSDL 1.1 description in which the wsdl:port element has been extended with a wsa:EndpointReference, if WS-Addressing is engaged the SENDER MUST populate the [destination] and [reference parameters] properties of that request message with the values of the [address] and [reference parameters] properties (respectively) of the extending endpoint reference. CORE TESTABLE

Note that, since [address] is a required property of an endpoint reference, extending a wsdl:port with a wsa:EndpointReference has the effect of populating the [destination] property of the outgoing message, thus mandating the inclusion of the wsa:To header.

The second case is where the wsdl:port has not been extended with a wsa:EndpointReference .

R1155 When sending a request message to an endpoint which is specified by a WSDL 1.1 description in which the wsdl:port element has not been extended with a wsa:EndpointReference, if WS-Addressing is engaged the SENDER MAY populate the [destination] message address property of the request message with the value of the location attribute of the wsoap12:address extension element. CORE TESTABLE

3.7.16 Combining Synchronous and Asynchronous Operations

WS-Addressing 1.0 - Metadata defines a policy assertion, wsam:Addressing , that is used to indicate whether WS-Addressing is supported or required. It is a nested policy container assertion and can contain additional restrictions (specifically the wsam:AnonymousResponses and wsam:NonAnonymousResponses policy assertions) on the value of the response endpoint EPRs in request messages. A top-level assertion without any nested assertions implies that both anonymous and non-anonymous are allowed. The WS-Addressing 1.0 - Metadata specification sets the scope of this assertion to be endpoint policy subject. However, with regards to the anonymous/non-anonymous restrictions, experience has shown that it is often desirable to have different policies for different operations on the same endpoint. For example, some of the operations of an endpoint may need to be synchronous while others may need to be asynchronous. It is worthwhile to indicate this difference in a WSDL description. In the absence of any guidance on the mechanism(s) for expressing such per-operation distinctions, individual implementations will create their own extensions for enabling this feature. To avoid the interoperability problems inherent in such an approach, the Profile defines the following extension to the behavior defined by WS-Addressing 1.0 Metadata.

WS-Addressing 1.0 Metadata allows policies containing the wsam:Addressing policy assertion to be attached to either a wsdl:port or a wsdl:binding . To these two options the Profile adds a third option which allows policies containing the wsam:Addressing policy assertion to be attached to wsdl:binding/wsdl:operation elements. When the wsam:Addressing policy assertion is attached to the wsdl:binding/wsdl:operation element, it applies to the operation policy subject. Nevertheless, it should always be the case that if one operation of an endpoint supports or requires WS-Addressing, then all operations of that endpoint must support or require WS-Addressing (although, potentially, with different restrictions). Furthermore, to simplify the calculation of the effective policy for each operation and decrease the possibility of creating conflicting policies, each operation within such an endpoint should affirmatively declare its policy with respect to WS-Addressing.

R1156 In a DESCRIPTION, a policy that contains the wsam:Addressing assertion MUST be attached to either a wsdl:port, a wsdl:binding or a wsdl:binding/wsdl:operation. CORE NOT_TESTABLE_XPATH

R1157 If a DESCRIPTION has a policy alternative containing the wsam:Addressing assertion attached to a wsdl:binding/wsdl:operation, then all of the wsdl:operations within that wsdl:binding MUST also have a policy alternative containing the wsam:Addressing assertion attached to them. CORE NOT_TESTABLE_XPATH

In addition to the above restrictions and as stated in R1158 , the effective policy alternatives for a given policy subject must not contain conflicting assertions.

For example,

INCORRECT:

<wsdl:binding name="sc009SOAP12Binding" type="tns:sc009PortType">
  <wsp:Policy>
    <wsam:Addressing>
      <wsp:Policy/>
    </wsam:Addressing>
  </wsp:Policy>
  ...
  <wsdl:operation name="CreatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="GetPOStatus">
    ...
  </wsdl:operation>

  <wsdl:operation name="UpdatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="CancelPO">
    ...
  </wsdl:operation>
</wsdl:binding>

<wsdl:service name="sc009Service">
  <wsdl:port name="soap12port" binding="tns:sc009SOAP12Binding">
    ...
  </wsdl:port>
</wsdl:service>

The above example is incorrect for two reasons. Firstly, it violates R1157 because the GetPOStatus and CancelPO operations do not have policies containing the wsam:Addressing assertion attached to them. Secondly, the effective policies for both the CreatePO and UpdatePO operations contain conflicting assertions (a wsam:Addressing assertion that is unconstrained with regards to anonymous/non-anonymous and a wsam:Addressing assertion that is constrained to just non-anonymous) within the same alternative.

For example,

INCORRECT:

<wsdl:binding name="sc009SOAP12Binding" type="tns:sc009PortType">
  ...
  <wsdl:operation name="CreatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="GetPOStatus">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy/>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="UpdatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="CancelPO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy/>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>
</wsdl:binding>

<wsdl:service name="sc009Service">
  <wsdl:port name="soap12port" binding="tns:sc009SOAP12Binding">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy/>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:port>
</wsdl:service>
          

The above example is incorrect because the effective policies for both the CreatePO and UpdatePO operations contain conflicting assertions (a wsam:Addressing assertion that is unconstrained with regards to nnonymous/non-anonymous and a wsam:Addressing assertion that is constrained to just non-anonymous) within the same alternative.

For example,

CORRECT:

<wsdl:binding name="sc009SOAP12Binding" type="tns:sc009PortType">
  ...
  <wsdl:operation name="CreatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="GetPOStatus">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy/>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="UpdatePO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy>
          <wsam:NonAnonymousResponses/>
        </wsp:Policy>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>

  <wsdl:operation name="CancelPO">
    <wsp:Policy>
      <wsam:Addressing>
        <wsp:Policy/>
      </wsam:Addressing>
    </wsp:Policy>
    ...
  </wsdl:operation>
</wsdl:binding>

<wsdl:service name="sc009Service">
  <wsdl:port name="soap12port" binding="tns:sc009SOAP12Binding">
    ...
  </wsdl:port>
</wsdl:service>
          

The above example is correct. All of the operations in the soap12port of the s009Service require WS-Addressing. While the reponse EPRs for GetPOStatus and CancelPO are unconstrained, the response EPRs for the CreatePO and UpdatePO operations must be non-anonymous.

3.7.17 Conflicting Addressing Policies

When used together, the wsam:AnonymousResponses and wsam:NonAnonymousResponses nested policy assertions could result in an effective policy that contradicts WS-Addressing 1.0 - Metadata (i.e. "request messages sent to this endpoint must use response endpoint EPRs that simultaneously do and do not contain the WS-Addressing anonymous URI"). The Profile restricts the use of the wsam:AnonymousResponses and wsam:NonAnonymousResponses nested policy assertions to avoid this situation.

R1158 In a DESCRIPTION the effective policy for a given endpoint MUST NOT contain both the wsam:AnonymousResponses and wsam:NonAnonymousResponses assertions within a single policy alternative. CORE NOT_TESTABLE_XPATH

In cases where there are multiple policy alternatives within the effective policy, some which violate R1158 and some which do not, consumers MAY consider those policy alternatives that do not violate R1158.

4. Service Description

The Profile uses Web Services Description Language (WSDL) to enable the description of services as sets of endpoints operating on messages.

This section of the Profile incorporates the following specifications by reference, and defines extensibility points within them:

4.1 Required Description

An instance of a Web service is required to make the contract that it operates under available in some fashion.

R0001 Either an INSTANCE's WSDL 1.1 description, its UDDI binding template, or both MUST be available to an authorized consumer upon request. CORE TESTABLE BP2703

This means that if an authorized consumer requests a service description of a conformant service instance, then the service instance provider must make the WSDL document, the UDDI binding template, or both available to that consumer. A service instance may provide run-time access to WSDL documents from a server, but is not required to do so in order to be considered conformant. Similarly, a service instance provider may register the instance provider in a UDDI registry, but is not required to do so to be considered conformant. In all of these scenarios, the WSDL contract must exist, but might be made available through a variety of mechanisms, depending on the circumstances.

4.2 Document Structure

WSDL 1.1, Section 2.1 defines the overall structure of an XML document for describing Web services. The Profile mandates the use of that structure, and places the following constraints on its use:

4.2.1 WSDL Schema Definitions

The normative schemas for WSDL appearing in Appendix 4 of the WSDL 1.1 specification have inconsistencies with the normative text of the specification. The Profile references new schema documents that have incorporated fixes for known errors.

R2028 A DESCRIPTION using the WSDL namespace (prefixed "wsdl" in this Profile) MUST be valid according to the XML Schema found at "http://ws-i.org/profiles/basic/1.1/wsdl-2004-08-24.xsd". CORE TESTABLE BP2705

R2029 A DESCRIPTION using the WSDL SOAP binding namespace (prefixed "wsoap12" in this Profile) MUST be valid according to the XML Schema found at " http://schemas.xmlsoap.org/wsdl/soap12/wsdl11soap12-20060302.xsd". CORE TESTABLE BP2704

Although the Profile requires WSDL descriptions to be Schema valid, it does not require consumers to validate WSDL documents. It is the responsibility of a WSDL document's author to assure that it is Schema valid.

4.2.2 WSDL and Schema Import

Some examples in WSDL 1.1 incorrectly show the WSDL import statement being used to import XML Schema definitions. The Profile clarifies use of the import mechanisms to keep them consistent and confined to their respective domains. Imported schema documents are also constrained by XML version and encoding requirements consistent to those of the importing WSDL documents.

R2001 A DESCRIPTION MUST only use the WSDL "import" statement to import another WSDL description. CORE TESTABLE BP2101

R2803 In a DESCRIPTION, the namespace attribute of the wsdl:import MUST NOT be a relative URI. CORE TESTABLE BP2803

R2002 To import XML Schema Definitions, a DESCRIPTION MUST use the XML Schema "import" statement. CORE TESTABLE BP2101

R2003 A DESCRIPTION MUST use the XML Schema "import" statement only within the xsd:schema element of the types section. CORE TESTABLE BP2103

R2004 In a DESCRIPTION the schemaLocation attribute of an xsd:import element MUST NOT resolve to any document whose root element is not "schema" from the namespace "http://www.w3.org/2001/XMLSchema". CORE TESTABLE BP2106

R2009 An XML Schema directly or indirectly imported by a DESCRIPTION MAY include the Unicode Byte Order Mark (BOM). CORE NOT_TESTED

R2010 An XML Schema directly or indirectly imported by a DESCRIPTION MUST use either UTF-8 or UTF-16 encoding. CORE TESTABLE BP2202

R2011 An XML Schema directly or indirectly imported by a DESCRIPTION MUST use version 1.0 of the eXtensible Markup Language W3C Recommendation. CORE NOT_TESTABLE

For example,

INCORRECT:

<definitions name="StockQuote"
             targetNamespace="http://example.com/stockquote/definitions"
             xmlns:sq="http://example.com/stockquote"
             ...
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <import namespace="http://example.com/stockquote"
           location="http://example.com/stockquote/schemas/stockquote.xsd"/>

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
</definitions>

CORRECT:

<definitions name="StockQuote"
             targetNamespace="http://example.com/stockquote/definitions"
             xmlns:sq="http://example.com/stockquote"
             ...
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <import namespace="http://example.com/stockquote/definitions"
          location="http://example.com/stockquote/definitions/stockquote.wsdl"/>

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
</definitions>

CORRECT:

<definitions name="StockQuote"
             targetNamespace="http://example.com/stockquote/definitions"
             xmlns:sq="http://example.com/stockquote"
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             ...
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <types>
    <xsd:schema targetNamespace="http://example.com/stockquote">
      <xsd:import namespace="http://example.com/stockquote"
                  schemaLocation="http://example.com/stockquote/schemas/stockquote.xsd"/>
      <xsd:element name="TradePriceRequest" type="bt:PriceRequestType"/>
    </xsd:schema>
  </types>

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
</definitions>

4.2.3 WSDL Import location Attribute Structure

WSDL 1.1 is not clear about whether the location attribute of the wsdl:import statement is required, or what its content is required to be.

R2007 A DESCRIPTION MUST specify a non-empty location attribute on the wsdl:import element. CORE TESTABLE BP2098

Although the wsdl:import statement is modeled after the xsd:import statement, the location attribute is required by wsdl:import while the corresponding attribute on xsd:import , schemaLocation is optional. Consistent with location being required, its content is not intended to be empty.

4.2.4 WSDL Import location Attribute Semantics

WSDL 1.1 is unclear about whether WSDL processors must actually retrieve and process the WSDL document from the URI specified in the location attribute on the wsdl:import statements it encounters.

R2008 A CONSUMER MAY, but need not, retrieve a WSDL description from the URI specified in the location attribute on a wsdl:import element. CORE NOT_TESTED

The value of the location attribute of a wsdl:import element is a hint. A WSDL processor may have other ways of locating a WSDL description for a given namespace.

4.2.5 Placement of WSDL import Elements

Example 3 in WSDL 1.1 Section 3.1 causes confusion regarding the placement of wsdl:import .

R2022 When they appear in a DESCRIPTION, wsdl:import elements MUST precede all other elements from the WSDL namespace except wsdl:documentation. CORE TESTABLE BP2105

R2023 When they appear in a DESCRIPTION, wsdl:types elements MUST precede all other elements from the WSDL namespace except wsdl:documentation and wsdl:import. CORE TESTABLE BP2018

For example,

INCORRECT:

<definitions name="StockQuote"
             ...
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
  <import namespace="http://example.com/stockquote/definitions"
          location="http://example.com/stockquote/definitions/stockquote.wsdl"/>
  ...
  <service name="StockQuoteService">
    <port name="StockQuotePort" binding="tns:StockQuoteSoap">
      ...
    </port>
  </service>
</definitions>

CORRECT:

<definitions name="StockQuote"
             ...
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <import namespace="http://example.com/stockquote/definitions"
          location="http://example.com/stockquote/definitions/stockquote.wsdl"/>

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
  <service name="StockQuoteService">
    <port name="StockQuotePort" binding="tns:StockQuoteSoap">
      ...
    </port>
  </service>
</definitions>

INCORRECT:

<definitions name="StockQuote"
             ...
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
  <service name="StockQuoteService">
    <port name="StockQuotePort" binding="tns:StockQuoteSoap">
      ...
    </port>
  </service>

  <types>
    <xsd:schema targetNamespace="http://example.com/stockquote">
      ...
    </xsd:schema>
  </types>
</definitions>

CORRECT:

<definitions name="StockQuote"
             ...
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             xmlns="http://schemas.xmlsoap.org/wsdl/">

  <import namespace="http://example.com/stockquote/definitions"
          location="http://example.com/stockquote/definitions/stockquote.wsdl"/>

  <types>
    <xsd:schema targetNamespace="http://example.com/stockquote">
      ...
    </xsd:schema>
  </types>

  <message name="GetLastTradePriceInput">
    <part name="body" element="sq:TradePriceRequest"/>
  </message>
  ...
  <service name="StockQuoteService">
    <port name="StockQuotePort" binding="tns:StockQuoteSoap">
      ...
    </port>
  </service>
</definitions>

4.2.6 XML Version Requirements

Neither WSDL 1.1 nor XML Schema 1.0 mandate a particular version of XML. For interoperability, WSDL documents and the schemas they import expressed in XML must use version 1.0.

R4004 A DESCRIPTION MUST use version 1.0 of the eXtensible Markup Language W3C Recommendation. CORE TESTABLE BP2700

4.2.7 XML Namespace Declarations

Although published errata NE05 (see http://www.w3.org/XML/xml-names-19990114-errata) allows this namespace declaration to appear, some older processors considered such a declaration to be an error. This requirement ensures that conformant artifacts have the broadest interoperability possible.

R4005 A DESCRIPTION SHOULD NOT contain the namespace declaration xmlns:xml="http://www.w3.org/XML/1998/namespace". CORE TESTABLE BP2034

As this Profile allows for the use of protocol bindings other than HTTP, the transport is responsible for defining how encoding is handled as specified in Section 2.2 for Simple SOAP and XOP encoded messages using HTTP. This applies to Sections 4.2.8 and 4.2.9. For HTTP, transport protocol constraints are identified in RFC 3023 .

4.2.8 WSDL and the Unicode BOM

XML 1.0 allows documents that use the UTF-8 character encoding to include a BOM; therefore, description processors must be prepared to accept them.

R4002 A DESCRIPTION MAY include the Unicode Byte Order Mark (BOM). CORE NOT_TESTED

4.2.9 Acceptable WSDL Character Encodings

The Profile consistently requires either UTF-8 or UTF-16 encoding for both SOAP and WSDL.

R4003 A DESCRIPTION MUST use either UTF-8 or UTF-16 encoding. CORE TESTABLE BP2201

4.2.10 Namespace Coercion

Namespace coercion on wsdl:import is disallowed by the Profile.

R2005 The targetNamespace attribute on the wsdl:definitions element of a description that is being imported MUST have same the value as the namespace attribute on the wsdl:import element in the importing DESCRIPTION. CORE TESTABLE BP2104

4.2.11 WSDL documentation Element

The WSDL 1.1 schema and the WSDL 1.1 specification are inconsistent with respect to where wsdl:documentation elements may be placed.

R2030 In a DESCRIPTION the wsdl:documentation element MAY be present as the first child element of wsdl:import, wsdl:part and wsdl:definitions in addition to the elements cited in the WSDL 1.1 specification. CORE NOT_TESTED

4.2.12 WSDL Extensions

Requiring support for WSDL extensions that are not explicitly specified by this or another WS-I Profile can lead to interoperability problems with development tools that have not been instrumented to understand those extensions.

R2025 A DESCRIPTION containing WSDL extensions MUST NOT use them to contradict other requirements of the Profile. CORE NOT_TESTABLE

R2026 A DESCRIPTION SHOULD NOT include extension elements with a wsdl:required attribute value of "true" on any WSDL construct (wsdl:binding, wsdl:portType, wsdl:message, wsdl:types or wsdl:import) that claims conformance to the Profile. CORE TESTABLE BP2123

R2027 If during the processing of a description, a consumer encounters a WSDL extension element that has a wsdl:required attribute with a boolean value of "true" that the consumer does not understand or cannot process, the CONSUMER MUST fail processing. CORE NOT_TESTABLE

Development tools that consume a WSDL description and generate software for a Web service instance might not have built-in understanding of an unknown WSDL extension. Hence, use of required WSDL extensions should be avoided. Use of a required WSDL extension that does not have an available specification for its use and semantics imposes potentially insurmountable interoperability concerns for all but the author of the extension. Use of a required WSDL extension that has an available specification for its use and semantics reduces, but does not eliminate the interoperability concerns that lead to this refinement.

For the purposes of the Profile, all elements in the "http://schemas.xmlsoap.org/wsdl/" namespace are extensible via element as well as attributes. As a convenience, WS-I has published a version of the WSDL 1.1 schema that reflects this capability at: http://ws-i.org/profiles/basic/1.1/wsdl-2004-08-24.xsd

4.3 Types

WSDL 1.1, Section 2.2 defines the wsdl:types element to enclose data type definitions that are relevant to the Web service described. The Profile places the following constraints pertinent to those portions of the content of the wsdl:types element that are referred to by WSDL elements that make Profile conformance claims:

4.3.1 QName References

XML Schema requires each QName reference to use either the target namespace, or an imported namespace (one marked explicitly with an xsd:import element). QName references to namespaces represented only by nested imports are not allowed.

WSDL 1.1 is unclear as to which schema target namespaces are suitable for QName references from a WSDL element. The Profile allows QName references from WSDL elements both to the target namespace defined by the xsd:schema element, and to imported namespaces. QName references to namespaces that are only defined through a nested import are not allowed.

R2101 A DESCRIPTION MUST NOT use QName references to WSDL components in namespaces that have been neither imported, nor defined in the referring WSDL document. CORE TESTABLE BP2416

R2102 A QName reference to a Schema component in a DESCRIPTION MUST use the namespace defined in the targetNamespace attribute on the xsd:schema element, or to a namespace defined in the namespace attribute on an xsd:import element within the xsd:schema element. CORE TESTABLE BP2417

4.3.2 Schema targetNamespace Structure

Requiring a targetNamespace on all xsd:schema elements that are children of wsdl:types is a good practice, places a minimal burden on authors of WSDL documents, and avoids the cases that are not as clearly defined as they might be.

R2105 All xsd:schema elements contained in a wsdl:types element of a DESCRIPTION MUST have a targetNamespace attribute with a valid and non-null value, UNLESS the xsd:schema element has xsd:import and/or xsd:annotation as its only child element(s). CORE TESTABLE BP2107

4.3.3 soapenc:Array

The recommendations in WSDL 1.1 Section 2.2 for declaration of array types have been interpreted in various ways, leading to interoperability problems. Further, there are other clearer ways to declare arrays.

R2110 In a DESCRIPTION, declarations MUST NOT extend or restrict the soapenc:Array type. CORE TESTABLE BP2108b

R2111 In a DESCRIPTION, declarations MUST NOT use wsdl:arrayType attribute in the type declaration. CORE TESTABLE BP2108a

R2112 In a DESCRIPTION, elements SHOULD NOT be named using the convention ArrayOfXXX. CORE TESTABLE BP2110

R2113 An ENVELOPE MUST NOT include the soapenc:arrayType attribute. CORE TESTABLE BP1204

For example,

INCORRECT:

Given the WSDL Description:

<xsd:element name="MyArray2" type="tns:MyArray2Type"/>
<xsd:complexType name="MyArray2Type"
                 xmlns:soapenc="http://www.w3.org/2003/05/soap-encoding"
                 xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
  <xsd:complexContent>
    <xsd:restriction base="soapenc:Array">
      <xsd:sequence>
        <xsd:element name="x" type="xsd:string" minOccurs="0" maxOccurs="unbounded"/>
      </xsd:sequence>
      <xsd:attribute ref="soapenc:arrayType" wsdl:arrayType="tns:MyArray2Type[]"/>
    </xsd:restriction> </xsd:complexContent>
  </xsd:complexType>
            

The envelope would serialize as (omitting namespace declarations for clarity):

<MyArray2 soapenc:arrayType="tns:MyArray2Type[]">
  <x>abcd</x>
  <x>efgh</x>
</MyArray2>
            

CORRECT:

Given the WSDL Description:

<xsd:element name="MyArray1" type="tns:MyArray1Type"/>
<xsd:complexType name="MyArray1Type">
  <xsd:sequence>
    <xsd:element name="x" type="xsd:string" minOccurs="0" maxOccurs="unbounded"/>
  </xsd:sequence>
</xsd:complexType>
            

The envelope would serialize as (omitting namespace declarations for clarity):

<MyArray1>
  <x>abcd</x>
  <x>efgh</x>
</MyArray1>
            

4.3.4 WSDL and Schema Definition Target Namespaces

The names defined by schemas and the names assigned to WSDL definitions are in separate symbol spaces.

R2114 The target namespace for WSDL definitions and the target namespace for schema definitions in a DESCRIPTION MAY be the same. CORE NOT_TESTED

4.3.5 Multiple GED Definitions with the same QName

The schema components of all the xs:schema children, and their imports and includes, of the wsdl:types element comprise a single symbol space containing all the global element declarations. Thus, when global element declarations share a qualified name, a single component will be represented in the symbol space. If two declarations are identical, there is no ambiguity in the structure of the component, but if the declarations differ, it is indeterminate as to which of the declarations will be represented, which may lead to interoperability problems. Because defining an equivalence algorithm is impractical, this requirement warns against any appearance of declarations with the same qualified name. However, duplicate declarations are not strictly prohibited, as user inspection may determine that two declarations are actually identical (e.g. they were imported from the same set of components) and thus are unlikely to cause interoperability problems.

R2115 A DESCRIPTION SHOULD NOT contain multiple global element declarations that share the same qualified name. CORE TESTABLE BP2124

4.3.6 Multiple Type Definitions with the same QName

The schema components of all the xs:schema children, and their imports and includes, of the wsdl:types element comprise single symbol spaces containing all the type definitions. Thus, when type definitions share a qualified name, a single component will be represented in the symbol space. If two definitions are identical, there is no ambiguity in the structure of the component, but if the definitions differ, it is indeterminate as to which of the definitions will be represented, which may lead to interoperability problems. Because defining an equivalence algorithm is impractical, this requirement warns against any appearance of definitions with the same qualified name. However, duplicate definitions are not strictly prohibited, as user inspection may determine that two definitions are actually identical (e.g. they were imported from the same set of components) and thus are unlikely to cause interoperability problems.

R2116 A DESCRIPTION SHOULD NOT contain multiple type definitions that share the same qualified name. CORE TESTABLE BP2125

4.4 Messages

WSDL 1.1, Section 2.3 defines the wsdl:message elements that are used to represent abstract definitions of the data being transmitted. It uses wsdl:binding elements to define how the abstract definitions are bound to a specific message serialization. The Profile places the following constraints on wsdl:message elements and on how conformant wsdl:binding elements may use wsdl:message element(s).

In this section the following definitions are used to make the requirements more compact and easier to understand.

Definition: rpc-literal binding

An "rpc-literal binding" is a wsdl:binding element whose child wsdl:operation elements are all rpc-literal operations.

An "rpc-literal operation" is a wsdl:operation child element of wsdl:binding whose wsoap12:body descendant elements specify the use attribute with the value "literal", and either:

  1. The style attribute with the value "rpc" is specified on the child wsoap12:operation element; or
  2. The style attribute is not present on the child wsoap12:operation element, and the wsoap12:binding element in the enclosing wsdl:binding specifies the style attribute with the value "rpc".

Definition: document-literal binding

A "document-literal binding" is a wsdl:binding element whose child wsdl:operation elements are all document-literal operations.

A "document-literal operation" is a wsdl:operation child element of wsdl:binding whose wsoap12:body descendent elements specifies the use attribute with the value "literal" and, either:

  1. The style attribute with the value "document" is specified on the child wsoap12:operation element; or
  2. The style attribute is not present on the child wsoap12:operation element, and the wsoap12:binding element in the enclosing wsdl:binding specifies the style attribute with the value "document"; or
  3. The style attribute is not present on both the child wsoap12:operation element and the wsoap12:binding element in the enclosing wsdl:binding .

4.4.1 Bindings and Parts

There are various interpretations about how many wsdl:part elements are permitted or required for document-literal and rpc-literal bindings and how they must be defined.

R2201 A document-literal binding in a DESCRIPTION MUST, in each of its wsoap12:body element(s), have at most one part listed in the parts attribute, if the parts attribute is specified. CORE TESTABLE BP2111

R2210 If a document-literal binding in a DESCRIPTION does not specify the parts attribute on a wsoap12:body element, the corresponding abstract wsdl:message MUST define zero or one wsdl:parts. CORE TESTABLE BP2119

R2202 A wsdl:binding in a DESCRIPTION MAY contain wsoap12:body element(s) that specify that zero parts form the soap12:Body. CORE NOT_TESTED

R2203 An rpc-literal binding in a DESCRIPTION MUST refer, in its wsoap12:body element(s), only to wsdl:part element(s) that have been defined using the type attribute. CORE TESTABLE BP2013

R2211 An ENVELOPE described with an rpc-literal binding MUST NOT have the xsi:nil attribute with a value of "1" or "true" on the part accessors. CORE TESTABLE BP1211a BP1211b

R2207 A wsdl:message in a DESCRIPTION MAY contain wsdl:parts that use the elements attribute provided those wsdl:parts are not referred to by a wsoap12:body in an rpc-literal binding. CORE NOT_TESTED

R2204 A document-literal binding in a DESCRIPTION MUST refer, in each of its wsoap12:body element(s), only to wsdl:part element(s) that have been defined using the element attribute. CORE TESTABLE BP2012

R2208 A binding in a DESCRIPTION MAY contain wsoap12:header element(s) that refer to wsdl:parts in the same wsdl:message that are referred to by its wsoap12:body element(s). CORE NOT_TESTED

R2212 An ENVELOPE described using an rpc-literal binding MUST contain exactly one part accessor element for each of the wsdl:part elements bound to the wsoap12:body element in the rpc-literal binding corresponding to the envelope. CORE TESTABLE BP1212a BP1212b

R2213 In a doc-literal description where the value of the parts attribute of wsoap12:body is an empty string, the corresponding ENVELOPE MUST have no element content in the soap12:Body element. CORE TESTABLE BP1213a BP1213b

R2214 In a rpc-literal description where the value of the parts attribute of wsoap12:body is an empty string, the corresponding ENVELOPE MUST have no part accessor elements. CORE TESTABLE BP1214a BP1214b

Use of wsdl:message elements with zero parts is permitted in Document styles to permit operations that can send or receive envelopes with empty soap12:Body s. Use of wsdl:message elements with zero parts is permitted in RPC styles to permit operations that have no (zero) parameters and/or a return value.

For document-literal bindings, the Profile requires that at most one part, abstractly defined with the element attribute, be serialized into the soap12:Body element.

When a wsdl:part element is defined using the type attribute, the serialization of that part in a message is equivalent to an implicit (XML Schema) qualification of a minOccurs attribute with the value "1", a maxOccurs attribute with the value "1" and a nillable attribute with the value "false".

It is necessary to specify the equivalent implicit qualification because the wsdl:part element does not allow one to specify the cardinality and nillability rules. Specifying the cardinality and the nillability rules facilitates interoperability between implementations. The equivalent implicit qualification for nillable attribute has a value of "false" because if it is specified to be "true" one cannot design a part whereby the client is always required to send a value. For applications that want to allow the wsdl:part to to be nillable, it is expected that applications will generate a complexType wrapper and specify the nillability rules for the contained elements of such a wrapper.

4.4.2 Bindings and Faults

There are several interpretations for how wsdl:part elements that describe wsoap12:fault , wsoap12:header , and wsoap12:headerfault may be defined.

R2205 A wsdl:binding in a DESCRIPTION MUST refer, in each of its wsoap12:header, wsoap12:headerfault and wsoap12:fault elements, only to wsdl:part element(s) that have been defined using the element attribute. CORE TESTABLE BP2113

Because faults and headers do not contain parameters, wsoap12:fault , wsoap12:header and wsoap12:headerfault assume, per WSDL 1.1, that the value of the style attribute is "document". R2204 requires that all wsdl:part elements with a style attribute whose value is "document" that are bound to wsoap12:body be defined using the element attribute. This requirement does the same for wsoap12:fault , wsoap12:header and wsoap12:headerfault elements.

4.4.3 Unbound portType Element Contents

WSDL 1.1 is not explicit about whether it is permissible for a wsdl:binding to leave the binding for portions of the content defined by a wsdl:portType unspecified.

R2209 A wsdl:binding in a DESCRIPTION SHOULD bind every wsdl:part of a wsdl:message in the wsdl:portType to which it refers to one of wsoap12:body, wsoap12:header, wsoap12:fault or wsoap12:headerfault. CORE TESTABLE BP2114

A portType defines an abstract contract with a named set of operations and associated abstract messages. Although not disallowed, it is expected that every part of the abstract input, output and fault messages specified in a portType is bound to wsoap12:body or wsoap12:header (and so forth) as appropriate when using the SOAP binding as defined in WSDL 1.1 Section 3. Un-bound wsdl:parts should be ignored.

4.4.4 Declaration of part Elements

Examples 4 and 5 in WSDL 1.1 Section 3.1 incorrectly show the use of XML Schema types (e.g. "xsd:string") as a valid value for the element attribute of a wsdl:part element.

R2206 A wsdl:message in a DESCRIPTION containing a wsdl:part that uses the element attribute MUST refer, in that attribute, to a global element declaration. CORE TESTABLE BP2115

For example,

INCORRECT:

<message name="GetTradePriceInput">
  <part name="tickerSymbol" element="xsd:string"/>
</message>

CORRECT:

<message name="GetTradePriceInput">
  <part name="body" element="tns:SubscribeToQuotes"/>
</message>

4.5 Port Types

WSDL 1.1, Section 2.4 defines the wsdl:portType elements that are used to group a set of abstract operations. The Profile places the following constraints on conformant wsdl:portType element(s):

4.5.1 Ordering of part Elements

Permitting the use of parameterOrder helps code generators in mapping between method signatures and messages on the wire.

R2301 The order of the elements in the soap12:Body of an ENVELOPE MUST be the same as that of the wsdl:parts in the wsdl:message that describes it for each of the wsdl:part elements bound to the envelope's corresponding wsoap12:body element. CORE TESTABLE BP1111a BP1111b BP1012a BP1012b

R2302 A DESCRIPTION MAY use the parameterOrder attribute of an wsdl:operation element to indicate the return value and method signatures as a hint to code generators. CORE NOT_TESTED

4.5.2 Allowed Operations

Solicit-Response and Notification operations are not well defined by WSDL 1.1; furthermore, WSDL 1.1 does not define bindings for them.

R2303 A DESCRIPTION MUST NOT use Solicit-Response and Notification type operations in a wsdl:portType definition. CORE TESTABLE BP2208

4.5.3 Distinctive Operations

Operation name overloading in a wsdl:portType is disallowed by the Profile.

R2304 A wsdl:portType in a DESCRIPTION MUST have operations with distinct values for their name attributes. CORE TESTABLE BP2010