WS-I

Basic Profile Version 1.2

Working Group Draft

2010-03-31

This version:
http://www.ws-i.org/Profiles/BasicProfile-1.2-2010-03-31.html
Latest version:
http://www.ws-i.org/Profiles/BasicProfile-1.2.html
Editors:
Robert Chumbley , IBM
Jacques Durand , Fujitsu
Micah Hainline , Asynchrony Solutions
Gilbert Pilz , Oracle
Tom Rutt , Fujitsu
Administrative contact:
secretary@ws-i.org

Abstract

This document defines the WS-I Basic Profile 1.2, 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

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Table of Contents

1. Introduction
1.1. Guiding Principles
1.2. Relationships to Other Profiles
1.2.1. Compatibility with Basic Profile 1.1
1.2.2. Relationship to Basic Profile 2.0
1.3. Test Assertions
1.4. Notational Conventions
1.5. 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
3.2. SOAP Envelopes
3.2.1. SOAP Envelope Structure
3.2.2. SOAP Envelope Namespace
3.2.3. SOAP Body Namespace Qualification
3.2.4. Disallowed Constructs
3.2.5. SOAP Trailers
3.2.6. SOAP encodingStyle Attribute
3.2.7. SOAP mustUnderstand Attribute
3.2.8. xsi:type Attributes
3.2.9. SOAP 1.1 attributes on SOAP 1.1 elements
3.3. SOAP Processing Model
3.3.1. Mandatory Headers
3.3.2. Generating mustUnderstand Faults
3.3.3. SOAP Fault Processing
3.4. SOAP Faults
3.4.1. Identifying SOAP Faults
3.4.2. SOAP Fault Structure
3.4.3. SOAP Fault Namespace Qualification
3.4.4. SOAP Fault Extensibility
3.4.5. SOAP Fault Language
3.4.6. SOAP Custom Fault Codes
3.5. Use of SOAP in HTTP
3.5.1. HTTP Protocol Binding
3.5.2. HTTP Methods and Extensions
3.5.3. SOAPAction HTTP Header
3.5.4. HTTP Success Status Codes
3.5.5. HTTP Redirect Status Codes
3.5.6. HTTP Client Error Status Codes
3.5.7. HTTP Server Error Status Codes
3.5.8. HTTP Cookies
3.5.9. 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 SOAPAction 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 Headers
3.7.8. Present and Understood WS-Addressing Headers
3.7.9. SOAP MustUnderstand or VersionMismatch fault Transmission
3.7.10. Faulting Behavior with Present and Understood WS-Addressing Headers
3.7.11. [message id] and One-Way Operations
3.7.12. Refusal to Honor WS-Addressing Headers
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 wsoap11 Elements
4.7.11. Consistency of portType and binding Elements
4.7.12. Describing headerfault Elements
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 SOAPAction
4.7.26. SOAP Binding Extensions
4.8. Use of XML Schema
4.9. 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 1.2 (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 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.

1.2 Relationships to Other Profiles

This Profile is derived from the Basic Profile 1.1 (BP 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.

1.2.1 Compatibility with Basic Profile 1.1

There are a few requirements in the Basic Profile 1.2 that may present compatibility issues with clients, services and their artifacts that have been engineered for Basic Profile 1.1 conformance. However, in general, the Basic Profile WG members have tried to preserve as much forwards and backwards compatibility with the Basic Profile 1.1 as possible so as not to disenfranchise clients, services and their artifacts that have been deployed in conformance with the Basic Profile 1.1.

This Profile uses the term 'backward compatible' to mean that an artifact, client or service that is conformant to the Basic Profile 1.2 will behave consistently with an implementation that is conformant with the Basic Profile 1.1. This Profile uses the term 'forward compatible' to mean that an artifact, client or service that is conformant with the Basic Profile 1.1 specification will be consistent with that of an implementation that is conformant with the Basic Profile 1.2.

This Profile has attempted to capture all known potential backwards and forwards compatibility issues below:

The list above is not meant to be authoritative.

1.2.2 Relationship to Basic Profile 2.0

Similarly to this Profile, Basic Profile 2.0 (BP 2.0) is derived from Basic Profile 1.1 . Unlike this Profile, the version of SOAP in scope for BP 2.0 is the W3C SOAP 1.2 Recommendation , not SOAP 1.1. To the extent possible, this Profile and BP 2.0 attempt to maintain a common set of requirement numbers, and common requirement and expository text. There are cases where the differences between SOAP 1.1 and SOAP 1.2 necessitate unique requirements and/or differing requirement and expository text. Therefore, some requirements and test assertions may present issues of a forward or backward compatibility.

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 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.

1.5 Profile Identification and Versioning

This document is identified by a name (in this case, Basic Profile) and a version number (here, 1.2). 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.

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 1.2 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 1.2 conformance claim URI(s) are:

The union of the requirements tagged as "HTTP-TRANSPORT" and "CORE" requirements comprise "BP 1.2 Complete".

3. Messaging

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

3.1 Message Serialization

This Profile is intended to compose with mechanisms to describe whether messages are encoded as SIMPLE_SOAP_MESSAGEs or XOP_ENCODED_MESSAGEs. As such it does not mandate that both of these 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 1.1 defines an XML structure for serializing messages, the envelope. This Profile places the following constraints on the use and serialization of the soap11: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.

As a consequence of this, in conjunction with SOAP 1.1's requirement to use the "text/xml" media type (which has a default character encoding of "us-ascii") on envelopes, the "charset" parameter must always be present on the envelope's content-type. A further consequence of this is that the encoding pseudo-attribute of XML declaration within the message is always ignored, in accordance with the requirements of both XML 1.0 and RFC3023, "XML Media Types".

The "charset" parameter of Content-Type HTTP header field must be used to determine the correct character encoding of the message, in absence of a "charset" parameter, the default value for charset (which is "us-ascii") must be used.

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

3.2 SOAP Envelopes

SOAP 1.1, Section 4 , 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

There are obvious interoperability problems if different implementations do not agree on the number of allowable children for the soap11:Body element.

R9980 An ENVELOPE MUST conform to the structure specified in SOAP 1.1 Section 4, "SOAP Envelope" (subject to amendment by the Profile). CORE TESTABLE BP1600

R9981 An ENVELOPE MUST have exactly zero or one child elements of the soap11:Body element. CORE TESTABLE BP1881

See the requirements in Section 4.4.1 for the corresponding, requisite constraints on a DESCRIPTION.

3.2.2 SOAP Envelope Namespace

SOAP 1.1 states that an envelope with a document element whose namespace name is other than "http://schemas.xmlsoap.org/soap/envelope/" should be discarded. The Profile requires that a fault be generated instead, to assure unambiguous operation.

R1015 A RECEIVER MUST generate a fault if they encounter an envelope whose document element is not soap11:Envelope . CORE NOT_TESTED

3.2.3 SOAP Body Namespace Qualification

The use of unqualified element names may cause naming conflicts, therefore qualified names must be used for the children of soap11:Body .

R1014 The children of the soap11:Body element in an ENVELOPE MUST be namespace qualified. CORE TESTABLE BP1202

3.2.4 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 3 of SOAP 1.1.

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

3.2.5 SOAP Trailers

The interpretation of sibling elements following the soap11:Body element is unclear. Therefore, such elements are disallowed.

R1011 An ENVELOPE MUST NOT have any element children of soap11:Envelope following the soap11:Body element. CORE TESTABLE BP1263

This requirement clarifies a mismatch between the SOAP 1.1 specification and the SOAP 1.1 XML Schema.

For example,

INCORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <p:Process xmlns:p="http://example.org/Operations"/>
  </soap11:Body>
  <m:Data xmlns:m='http://example.org/information' >
    Here is some data with the message
  </m:Data>
</soap11:Envelope>

CORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <p:Process xmlns:p="http://example.org/Operations">
      <m:Data xmlns:m="http://example.org/information">
        Here is some data with the message
      </m:Data>
    </p:Process>
  </soap11:Body>
</soap11:Envelope>

3.2.6 SOAP encodingStyle Attribute

The soap11:encodingStyle attribute is used to indicate the use of a particular scheme in the encoding of data into XML. However, this introduces complexity, as this function can also be served by the use of XML Namespaces. As a result, the Profile prefers the use of literal, non-encoded XML.

R1005 An ENVELOPE MUST NOT contain soap11:encodingStyle attributes on any of the elements whose namespace name is "http://schemas.xmlsoap.org/soap/envelope/". CORE TESTABLE BP2005

R1006 An ENVELOPE MUST NOT contain soap11:encodingStyle attributes on any element that is a child of soap11:Body . CORE TESTABLE BP2005

R1007 An ENVELOPE described in an rpc-literal binding MUST NOT contain soap11:encodingStyle attribute on any element that is a grandchild of soap11:Body . CORE NOT_TESTED

3.2.7 SOAP mustUnderstand Attribute

The soap11:mustUnderstand attribute has a restricted type of "xsd:boolean" that takes only "0" or "1". Therefore, only those two values are allowed.

R1013 An ENVELOPE containing a soap11:mustUnderstand attribute MUST only use the lexical forms "0" and "1". CORE TESTABLE BP1013

3.2.8 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 fault on the absence of the xsi:type attribute in envelopes, except in cases where this attribute is required to indicate a derived type (see XML Schema Part 1: Structures, Section 2.6.1). CORE NOT_TESTABLE

3.2.9 SOAP 1.1 attributes on SOAP 1.1 elements

R1032 The soap11:Envelope, soap11:Header, and soap11:Body elements in an ENVELOPE MUST NOT have attributes in the namespace "http://schemas.xmlsoap.org/soap/envelope/". CORE TESTABLE BP1032

3.3 SOAP Processing Model

SOAP 1.1, 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 Mandatory Headers

SOAP 1.1's processing model is underspecified with respect to the processing of mandatory header blocks. Mandatory header blocks are those children of the soap11:Header element bearing a soap11:mustUnderstand attribute with a value of "1".

R1025 A RECEIVER MUST handle envelopes in such a way that it appears that all checking of mandatory header blocks is performed before any actual processing. CORE NOT_TESTABLE

This requirement guarantees that no undesirable side effects will occur as a result of noticing a mandatory header block after processing other parts of the message.

3.3.2 Generating mustUnderstand Faults

The Profile requires that receivers generate a fault when they encounter header blocks targeted at them, that they do not understand.

R1027 A RECEIVER MUST generate a "soap11:MustUnderstand" fault when an envelope contains a mandatory header block (i.e., one that has a soap11:mustUnderstand attribute with the value "1") targeted at the receiver (via soap11:actor) that the receiver does not understand. CORE NOT_TESTABLE

3.3.3 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.

R1028 When a fault is generated by a RECEIVER, further processing SHOULD NOT be performed on the SOAP envelope aside from that which is necessary to rollback, or compensate for, any effects of processing the envelope prior to the generation of the fault. CORE NOT_TESTABLE

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 soap11:Body element, that element being the soap11:Fault element.

R1107 A RECEIVER MUST interpret a SOAP message as a Fault when the soap11:Body of the message has a single soap11:Fault child. CORE NOT_TESTABLE

3.4.2 SOAP Fault Structure

The Profile restricts the content of the soap11:Fault element to those elements explicitly described in SOAP 1.1.

R1000 When an ENVELOPE is a Fault, the soap11:Fault element MUST NOT have element children other than faultcode, faultstring, faultactor and detail. CORE TESTABLE BP1260

For example,

INCORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault>
      <faultcode>soap11:Client</faultcode>
      <faultstring>Invalid message format</faultstring>
      <faultactor>http://example.org/someactor</faultactor>
      <detail>There were lots of elements in the message that I did not understand.</detail>
      <m:Exception xmlns:m="http://example.org/faults/exceptions">
        <m:ExceptionType>Severe</m:ExceptionType>
      </m:Exception>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

CORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
      <faultcode>soap11:Client</faultcode>
      <faultstring>Invalid message format</faultstring>
      <faultactor>http://example.org/someactor</faultactor>
      <detail xmlns:m="http://example.org/faults/exceptions">
        <m:msg>There were lots of elements in the message that I did not understand.</m:msg>
        <m:Exception>
          <m:ExceptionType>Severe</m:ExceptionType>
        </m:Exception>
      </detail>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

3.4.3 SOAP Fault Namespace Qualification

The children of the soap11:Fault element are local to that element, therefore namespace qualification is unnecessary.

R1001 When an ENVELOPE is a Fault, the element children of the soap11:Fault element MUST be unqualified. CORE TESTABLE BP1261

For example,

INCORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault>
      <soap11:faultcode>soap11:Client</soap11:faultcode>
      <soap11:faultstring>Invalid message format</soap11:faultstring>
      <soap11:faultactor>http://example.org/someactor</soap11:faultactor>
      <soap11:detail>
        <m:msg xmlns:m="http://example.org/faults/exceptions">
          There were lots of elements in the message that I did not understand.
        </m:msg>
      </soap11:detail>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

CORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault>
      <faultcode>soap11:Client</faultcode>
      <faultstring>Invalid message format</faultstring>
      <faultactor>http://example.org/someactor</faultactor>
      <detail>
        <m:msg xmlns:m="http://example.org/faults/exceptions">
          There were lots of elements in the message that I did not understand.
       </m:msg>
      </detail>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

3.4.4 SOAP Fault Extensibility

For extensibility, additional attributes are allowed to appear on the detail element and additional elements are allowed to appear as children of the detail element.

R1002 A RECEIVER MUST accept faults that have any number of elements, including zero, appearing as children of the detail element. Such children can be qualified or unqualified. CORE NOT_TESTED

R1003 A RECEIVER MUST accept faults that have any number of qualified or unqualified attributes, including zero, appearing on the detail element. The namespace of qualified attributes can be anything other than "http://schemas.xmlsoap.org/soap/envelope/". CORE NOT_TESTED

3.4.5 SOAP Fault Language

Faultstrings are human-readable indications of the nature of a fault. As such, they may be in a particular language, and therefore the xml:lang attribute can be used to indicate the language of the faultstring.

Note that this requirement conflicts with the schema for SOAP appearing at its namespace URL. A schema without conflicts can be found at "http://ws-i.org/profiles/basic/1.1/soap-envelope-2004-01-21.xsd ".

R1016 A RECEIVER MUST accept faults that carry an xml:lang attribute on the faultstring element. CORE NOT_TESTED

3.4.6 SOAP Custom Fault Codes

SOAP 1.1 allows custom fault codes to appear inside the faultcode element, through the use of the "dot" notation.

Use of this mechanism to extend the meaning of the SOAP 1.1-defined fault codes can lead to namespace collision. Therefore, its use should be avoided, as doing so may cause interoperability issues when the same names are used in the right-hand side of the "." (dot) to convey different meaning.

Instead, the Profile encourages the use of the fault codes defined in SOAP 1.1, along with additional information in the detail element to convey the nature of the fault.

Alternatively, it is acceptable to define custom fault codes in a namespace controlled by the specifying authority.

A number of specifications have already defined custom fault codes using the "." (dot) notation. Despite this, their use in future specifications is discouraged.

R1004 When an ENVELOPE contains a faultcode element, the content of that element SHOULD be either one of the fault codes defined in SOAP 1.1 (supplying additional information if necessary in the detail element), or a Qname whose namespace is controlled by the fault's specifying authority (in that order of preference). CORE NOT_TESTABLE

R1031 When an ENVELOPE contains a faultcode element the content of that element SHOULD NOT use of the SOAP 1.1 "dot" notation to refine the meaning of the fault. CORE NOT_TESTABLE

It is recommended that applications that require custom fault codes either use the SOAP1.1 defined fault codes and supply additional information in the detail element, or that they define these codes in a namespace that is controlled by the specifying authority.

For example,

INCORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault>
      <faultcode>soap11:Server.ProcessingError</faultcode>
      <faultstring>An error occurred while processing the message</faultstring>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

CORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault xmlns:c="http://example.org/faultcodes">
      <faultcode>c:ProcessingError</faultcode>
      <faultstring>An error occured while processing the message</faultstring>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

CORRECT:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/">
  <soap11:Header/>
  <soap11:Body>
    <soap11:Fault>
      <faultcode>soap11:Server</faultcode>
      <faultstring>An error occured while processing the message</faultstring>
    </soap11:Fault>
  </soap11:Body>
</soap11:Envelope>

3.5 Use of SOAP in HTTP

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

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 6 of SOAP 1.1 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 HTTP Methods and Extensions

The SOAP1.1 specification defined its HTTP binding such that two possible methods could be used, the HTTP POST method and the HTTP Extension Framework's M-POST method. The Profile requires that only the HTTP POST method be used and precludes use of the HTTP Extension Framework.

R1132 A HTTP Request MESSAGE MUST use the HTTP POST method. HTTP-TRANSPORT TESTABLE BP1264

R1108 A MESSAGE MUST NOT use the HTTP Extension Framework (RFC2774). HTTP-TRANSPORT TESTABLE BP1262

The HTTP Extension Framework is an experimental mechanism for extending HTTP in a modular fashion. Because it is not deployed widely and also because its benefits to the use of SOAP are questionable, the Profile does not allow its use.

3.5.3 SOAPAction HTTP Header

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

3.5.4 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.

3.5.5 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.

3.5.6 HTTP Client Error Status Codes

HTTP uses the 4xx series of status codes to indicate failure due to a client error. Although there are a number of situations that may result in one of these codes, the Profile highlights those when the HTTP Request does not have the proper media type, and when the anticipated method ("POST") is not used.

R1125 An INSTANCE MUST use a 4xx HTTP status code for a response that indicates a problem with the format of a request. HTTP-TRANSPORT TESTABLE

R1113 An INSTANCE SHOULD use a "400 Bad Request" HTTP status code, if a HTTP Request message is malformed. HTTP-TRANSPORT NOT_TESTABLE

R1114 An INSTANCE SHOULD use a "405 Method not Allowed" HTTP status code if a HTTP Request message's method is not "POST". HTTP-TRANSPORT NOT_TESTABLE

R1115 An INSTANCE SHOULD use a "415 Unsupported Media Type" HTTP status code if a HTTP Request message's Content-Type header field-value is not permitted by its WSDL description. HTTP-TRANSPORT NOT_TESTABLE

Note that these requirements do not force an instance to respond to requests. In some cases, such as Denial of Service attacks, an instance may choose to ignore requests.

Also note that SOAP 1.1, Section 6.2 requires that SOAP Fault can only be returned with HTTP 500 "Internal Server Error" code. This profile doesn't change that requirement. When HTTP 4xx error status code is used, the response message should not contain a SOAP Fault.

3.5.7 HTTP Server Error Status Codes

HTTP uses the 5xx series of status codes to indicate failure due to a server error.

R1126 An INSTANCE MUST return a "500 Internal Server Error" HTTP status code if the response envelope is a Fault. HTTP-TRANSPORT TESTABLE BP1126

3.5.8 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 1.1 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).

3.5.9 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.

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:

Section 4.2.2 of SOAP 1.1 discusses the SOAP actor attribute. The value of this attribute is a URI. 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 1.1 defined URI, such as the actor value "http://schemas.xmlsoap.org/soap/actor/next", is treated as follows:

R1160 A RECEIVER, for the purposes of comparison of URI values of information items defined by the SOAP 1.1 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

3.7.4 Valid Values for SOAPAction When WS-Addressing is Used

There could be some confusion with regards to the range of valid values for the SOAPAction when WS-Addressing is used, given that the SOAP 1.1 specification permits the use of relative URIs.

When composed with WS-Addressing, the value of the SOAPAction HTTP header should be limited to an absolute URI that matches the value specified for wsa:Action . The empty string ("") is also allowed for special cases such as security considerations. For example, when the wsa:Action header is encrypted, set SOAPAction to "" as a way to avoid leakage.

R1144 When the wsa:Action SOAP header block is present in an envelope, the containing HTTP Request MESSAGE MUST specify a SOAPAction HTTP header with either a value that is an absolute URI that has the same value as the value of the wsa:Action header, or a value of "" (empty string). 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 1.1 defined MustUnderstand and VersionMismatch faults. This Profile mandates the use of the WS-Addressing defined wsa:Action value for SOAP 1.1 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 SOAP header element, when present, for either of the SOAP 1.1 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 soap11: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 Headers

When WS-Addressing headers are present in a SOAP envelope, but do not contain a soap11: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 header blocks, or contains WS-Addressing header blocks that do not include any soap11: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 Headers

When any WS-Addressing header blocks are present in a SOAP envelope (where soap11:mustUnderstand="1" attributes exist or the header contents are understood), any non-faulting response will be transmitted to the endpoint referred to by the wsa:ReplyTo header. 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 wsa:ReplyTo header or generate a fault instead (per R1029). CORE TESTABLE BP1146

SOAP 1.1 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:

<soap11:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/soap/envelope"
                 xmlns:wsa="http://www.w3.org/2005/08/addressing">
  <soap11: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>
    . . .
  </soap11:Header>
  <soap11:Body>
    . . .
  </soap11:Body>
</soap11: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 soap11: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 headers. 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 Headers

When WS-Addressing headers are present in a SOAP envelope (where soap11:mustUnderstand="1" attributes exist or the header contents are understood), should a fault be generated, it will be transmitted to the endpoint referred to by the wsa:FaultTo header. WS-Addressing specifies expected behavior should the wsa:FaultTo header 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 wsa:FaultTo SOAP header exists, the RECEIVER MUST NOT transmit faults to the endpoint referred to by the wsa:ReplyTo header. 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 transmit to the endpoint referred to by the wsa:ReplyTo header (R1146 ) and the wsa:FaultTo header 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 Headers

There may be many reasons (e.g. security, unsupported wsa:Address values, ...) why a RECEIVER does not honor any WS-Addressing headers. In these cases and irrespective of where the condition occurs, when any WS-Addressing headers are present in a SOAP envelope (where soap11:mustUnderstand=1 attributes exist or the header contents are understood), the RECEIVER must generate a fault.

R1149 If any WS-Addressing header blocks 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/soap11service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap11:Envelope ...>
 <soap11:Header>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap11:Header>
 <soap11:Body>
   ...
 </soap11:Body>
</soap11:Envelope>

CORRECT:

POST /NotifyEcho/soap11service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap11:Envelope ...>
 <soap11:Header>
    <wsa:To>http://www.w3.org/2005/08/addressing/anonymous</wsa:To>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap11:Header>
 <soap11:Body>
   ...
 </soap11:Body>
</soap11:Envelope>

CORRECT:

POST /NotifyEcho/soap11service HTTP/1.1
Content-Type: text/xml;charset=UTF-8
...
<soap11:Envelope ...>
 <soap11:Header>
    <wsa:To>http://www.example.org/NotifyEcho/soap11service</wsa:To>
    <wsa:Action>http://www.wstf.org/sc002/Echo</wsa:Action>
 </soap11:Header>
 <soap11:Body>
   ...
 </soap11:Body>
</soap11: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 the wsa:Action SOAP header block is present, the SENDER MUST populate the wsa:To and reference parameter SOAP headers of that request message with the values of the wsa:Address and wsa:ReferenceParameters elements (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 the wsa:Action SOAP header block is present, the SENDER MAY populate the wsa:To SOAP header of that request message with the value of the location attribute of the wsoap11: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="sc009SOAP11Binding" 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="soap11port" binding="tns:sc009SOAP11Binding">
    ...
  </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="sc009SOAP11Binding" 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="soap11port" binding="tns:sc009SOAP11Binding">
    <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="sc009SOAP11Binding" 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="soap11port" binding="tns:sc009SOAP11Binding">
    ...
  </wsdl:port>
</wsdl:service>

The above example is correct. All of the operations in the soap11port 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 "wsoap11" in this Profile) MUST be valid according to the XML Schema found at " http://schemas.xmlsoap.org/wsdl/soap/2004-08-24.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 wsoap11: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 wsoap11:operation element; or
  2. The style attribute is not present on the child wsoap11:operation element, and the wsoap11: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 wsoap11: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 wsoap11:operation element; or
  2. The style attribute is not present on the child wsoap11:operation element, and the wsoap11: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 wsoap11:operation element and the wsoap11: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 wsoap11: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 wsoap11:body element, the corresponding abstract wsdl:message MUST define zero or one wsdl:parts. CORE TESTABLE

R2202 A wsdl:binding in a DESCRIPTION MAY contain wsoap11:body element(s) that specify that zero parts form the soap11:Body. CORE NOT_TESTED

R2203 An rpc-literal binding in a DESCRIPTION MUST refer, in its wsoap11: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 wsoap11:body in an rpc-literal binding. CORE NOT_TESTED

R2204 A document-literal binding in a DESCRIPTION MUST refer, in each of its wsoap11: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 wsoap11:header element(s) that refer to wsdl:parts in the same wsdl:message that are referred to by its wsoap11: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 wsoap11: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 wsoap11:body is an empty string, the corresponding ENVELOPE MUST have no element content in the soap11:Body element. CORE TESTABLE BP1213a BP1213b

R2214 In a rpc-literal description where the value of the parts attribute of wsoap11: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 soap11: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 soap11: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 wsoap11:fault , wsoap11:header , and wsoap11:headerfault may be defined.

R2205 A wsdl:binding in a DESCRIPTION MUST refer, in each of its wsoap11:header, wsoap11:headerfault and wsoap11: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, wsoap11:fault , wsoap11:header and wsoap11: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 wsoap11:body be defined using the element attribute. This requirement does the same for wsoap11:fault , wsoap11:header and wsoap11: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 wsoap11:body, wsoap11:header, wsoap11:fault or wsoap11: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 wsoap11:body or wsoap11: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 soap11: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 wsoap11: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

Note that this requirement applies only to the wsdl:operation s within a given wsdl:portType . A wsdl:portType may have wsdl:operation s with names that are the same as those found in other wsdl:portType s.

4.5.4 parameterOrder Attribute Construction

WSDL 1.1 does not clearly state how the parameterOrder attribute of the wsdl:operation element (which is the child of the wsdl:portType element) should be constructed.

R2305 A wsdl:operation element child of a wsdl:portType element in a DESCRIPTION MUST be constructed so that the parameterOrder attribute, if present, omits at most 1 wsdl:part from the output message. CORE TESTABLE BP2014

If a wsdl:part from the output message is omitted from the list of wsdl:part s that is the value of the parameterOrder attribute, the single omitted wsdl:part is the return value. There are no restrictions on the type of the return value. If no part is omitted, there is no return value.

4.5.5 Exclusivity of type and element Attributes

WSDL 1.1 does not clearly state that both type and element attributes cannot be specified to define a wsdl:part in a wsdl:message .

R2306 A wsdl:message in a DESCRIPTION MUST NOT specify both type and element attributes on the same wsdl:part. CORE TESTABLE BP2116

4.6 Bindings

In WSDL 1.1, the wsdl:binding element supplies the concrete protocol and data format specifications for the operations and messages defined by a particular wsdl:portType . The Profile places the following constraints on conformant binding specifications:

4.6.1 Use of SOAP Binding

The Profile limits the choice of bindings to the well-defined and most commonly used SOAP 1.1 binding.

R2401 A wsdl:binding element in a DESCRIPTION MUST use the SOAP Binding as defined in WSDL 1.1, Section 3. CORE TESTABLE BP2402

Note that this places a requirement on the construction of conformant wsdl:binding elements. It does not place a requirement on descriptions as a whole; in particular, it does not preclude WSDL documents from containing non-conformant wsdl:binding elements. Also, a binding may have WSDL extensibility elements present which change how messages are serialized.

4.7 SOAP Binding

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

WSDL 1.1, Section 3 defines a binding for SOAP 1.1 endpoints. The Profile mandates the use of SOAP binding as defined in WSDL 1.1, and places the following constraints on its use:

4.7.1 Specifying the transport Attribute

There is an inconsistency between the WSDL 1.1 specification and the WSDL 1.1 schema regarding the transport attribute. The WSDL 1.1 specification requires it; however, the schema shows it to be optional.

R2701 The wsdl:binding element in a DESCRIPTION MUST be constructed so that its wsoap11:binding child element specifies the transport attribute. CORE TESTABLE BP2403

4.7.2 HTTP Transport

The profile limits the underlying transport protocol to HTTP.

R2702 When HTTP is used, a wsdl:binding element in a DESCRIPTION MUST specify the HTTP transport protocol with SOAP binding. Specifically, the transport attribute of its wsoap11:binding child MUST have the value "http://schemas.xmlsoap.org/soap/http". HTTP-TRANSPORT TESTABLE BP2404

Note that this requirement does not prohibit the use of HTTPS; See R5000.

4.7.3 Consistency of style Attribute

The style , "document" or "rpc", of an interaction is specified at the wsdl:operation level, permitting wsdl:binding s whose wsdl:operation s have different style s. This has led to interoperability problems. Additionally, use of document-literal binding, which generally allows for simpler implementations than the rpc-literal binding, is encouraged. This hint is not always appropriate, especially in the case of some existing implementations, which continue to be supported by this profile.

R2705 A wsdl:binding in a DESCRIPTION MUST either be a rpc-literal binding or a document-literal binding. CORE TESTABLE BP2017

4.7.4 Encodings and the use Attribute

The Profile prohibits the use of encodings, including the SOAP encoding.

R2706 A wsdl:binding in a DESCRIPTION MUST use the value of "literal" for the use attribute in all wsoap11:body, wsoap11:fault, wsoap11:header and wsoap11:headerfault elements. CORE TESTABLE BP2406

4.7.5 Multiple Bindings for portType Elements

The Profile explicitly permits multiple bindings for the same portType.

R2709 A wsdl:portType in a DESCRIPTION MAY have zero or more wsdl:bindings that refer to it, defined in the same or other WSDL documents. CORE NOT_TESTED

4.7.6 Operation Signatures

Definition: operation signature

The Profile defines the "operation signature" to be the fully qualified name of the child element of SOAP body of the SOAP input message described by an operation in a WSDL binding and the URI value of the wsa:Action SOAP header block, if present.

In the case of rpc-literal binding, the operation name is used as a wrapper for the part accessors. In the document-literal case, since a wrapper with the operation name is not present, the message signatures must be correctly designed so that they meet this requirement.

An endpoint that supports multiple operations must unambiguously identify the operation being invoked based on the input message that it receives. This is only possible if all the operations specified in the wsdl:binding associated with an endpoint have a unique operation signature.

R2710 The operations in a wsdl:binding in a DESCRIPTION MUST result in operation signatures that are different from one another. CORE TESTABLE BP2120a BP2120b

4.7.7 Multiple Ports on an Endpoint

When input messages destined for two different wsdl:port s at the same network endpoint are indistinguishable on the wire, it may not be possible to determine the wsdl:port being invoked by them. This may cause interoperability problems. However, there may be situations (e.g., SOAP versioning, application versioning, conformance to different profiles) where it is desirable to locate more than one port on an endpoint; therefore, the Profile allows this.

R2711 A DESCRIPTION SHOULD NOT have more than one wsdl:port with the same value for the location attribute of the wsoap11:address element. CORE TESTABLE BP2711

4.7.8 Child Element for Document-Literal Bindings

WSDL 1.1 is not completely clear what, in document-literal style bindings, the child element of soap11:Body is.

R2712 A document-literal binding MUST be serialized as an ENVELOPE with a soap11:Body whose child element is an instance of the global element declaration referenced by the corresponding wsdl:message part. CORE TESTABLE BP1011a BP1011b

4.7.9 One-Way Operations

There are differing interpretations of how HTTP is to be used when performing one-way operations. The SOAP 1.1 Request Optional Response HTTP Binding specification clarifies the expectations for the SOAP/HTTP binding.

R2714 For one-way operations, an HTTP Response MESSAGE MAY contain an envelope. HTTP-TRANSPORT NOT_TESTED

R2727 For one-way operations, a CONSUMER MUST NOT interpret a successful HTTP Response status code (i.e., 2xx) to mean the message is valid or that the receiver would process it. HTTP-TRANSPORT NOT_TESTABLE

One-way operations typically do not produce SOAP responses. However, some INSTANCEs may choose to communicate infrastructure-related faults (e.g. MustUnderstand, VersionMismatch) in the HTTP Response message. In addition to this, the use of some protocol extensions (e.g. WS-ReliableMessaging) may create the possibility for non-empty responses to one-way messages. For these reasons the Basic Profile 1.1 requirement that the HTTP Response message not contain a SOAP envelope has been relaxed. Note: the fact that an INSTANCE may choose to communicate infrastructure-related faults in the HTTP Response does not mean that the CONSUMER can expect it to do so.

The HTTP Response to a one-way operation indicates the success or failure of the transmission of the message. Based on the semantics of the different response status codes supported by the HTTP protocol, the Profile specifies that "200" and "202" are the preferred status codes that the sender should expect, signifying that the one-way message was received. A successful transmission does not indicate that the SOAP processing layer and the application logic has had a chance to validate the envelope or have committed to processing it.

4.7.10 Namespaces for wsoap11 Elements

There is confusion about what namespace is associated with the child elements of various children of soap11:Envelope , which has led to interoperability difficulties. The Profile defines these.

R2716 A document-literal binding in a DESCRIPTION MUST NOT have the namespace attribute specified on contained wsoap11:body, wsoap11:header, wsoap11:headerfault and wsoap11:fault elements. CORE TESTABLE BP2019

R2717 An rpc-literal binding in a DESCRIPTION MUST have the namespace attribute specified, the value of which MUST be an absolute URI, on contained wsoap11:body elements. CORE TESTABLE BP2020

R2726 An rpc-literal binding in a DESCRIPTION MUST NOT have the namespace attribute specified on contained wsoap11:header, wsoap11:headerfault and wsoap11:fault elements. CORE TESTABLE BP2117

In a document-literal SOAP binding, the serialized element child of the soap11:Body gets its namespace from the targetNamespace of the schema that defines the element. Use of the namespace attribute of the wsoap11:body element would override the element's namespace. This is not allowed by the Profile.

Conversely, in a rpc-literal SOAP binding, the serialized child element of the soap11:Body element consists of a wrapper element, whose namespace is the value of the namespace attribute of the wsoap11:body element and whose local name is either the name of the operation or the name of the operation suffixed with "Response". The namespace attribute is required, as opposed to being optional, to ensure that the children of the soap11:Body element are namespace-qualified.

4.7.11 Consistency of portType and binding Elements

The WSDL description must be consistent at both wsdl:portType and wsdl:binding levels.

R2718 A wsdl:binding in a DESCRIPTION MUST have the same set of wsdl:operations as the wsdl:portType to which it refers. CORE TESTABLE BP2118

4.7.12 Describing headerfault Elements

There is inconsistency between WSDL specification text and the WSDL schema regarding wsoap11:headerfault s.

R2719 A wsdl:binding in a DESCRIPTION MAY contain no wsoap11:headerfault elements if there are no known header faults. CORE NOT_TESTED

The WSDL 1.1 schema makes the specification of wsoap11:headerfault element mandatory on wsdl:input and wsdl:output elements of an operation, whereas the WSDL 1.1 specification marks them optional. The specification is correct.

4.7.13 Enumeration of Faults

A Web service description should include all faults known at the time the service is defined. There is also need to permit generation of new faults that had not been identified when the Web service was defined.

R2740 A wsdl:binding in a DESCRIPTION SHOULD contain a wsoap11:fault describing each known fault. CORE NOT_TESTABLE BP1107

R2741 A wsdl:binding in a DESCRIPTION SHOULD contain a wsoap11:headerfault describing each known header fault. CORE NOT_TESTED

R2742 An ENVELOPE MAY contain fault with a detail element that is not described by a wsoap11:fault element in the corresponding WSDL description. CORE NOT_TESTABLE

R2743 An ENVELOPE MAY contain the details of a header processing related fault in a SOAP header block that is not described by a wsoap11:headerfault element in the corresponding WSDL description. CORE NOT_TESTED

4.7.14 Type and Name of SOAP Binding Elements

The WSDL 1.1 schema disagrees with the WSDL 1.1 specification about the name and type of an attribute of the wsoap11:header and wsoap11:headerfault elements.

R2720 A wsdl:binding in a DESCRIPTION MUST use the part attribute with a schema type of "NMTOKEN" on all contained wsoap11:header and wsoap11:headerfault elements. CORE TESTABLE BP2021

R2749 A wsdl:binding in a DESCRIPTION MUST NOT use the parts attribute on contained wsoap11:header and wsoap11:headerfault elements. CORE TESTABLE BP2021

The WSDL Schema gives the attribute's name as "parts" and its type as "NMTOKENS". The schema is incorrect since each wsoap11:header and wsoap11:headerfault element references a single wsdl:part .

For example,

CORRECT:

<binding name="StockQuoteSoap" type="tns:StockQuotePortType">
  <wsoap11:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
  <operation name="SubscribeToQuotes">
    <input>
      <wsoap11:body parts="body" use="literal"/>
      <wsoap11:header message="tns:SubscribeToQuotes" part="subscribeheader" use="literal"/>
    </input>
  </operation>
</binding>

4.7.15 name Attribute on Faults

There is inconsistency between the WSDL 1.1 specification and the WSDL 1.1 schema, which does not list the name attribute.

R2721 A wsdl:binding in a DESCRIPTION MUST have the name attribute specified on all contained wsoap11:fault elements. CORE TESTABLE BP2022

R2754 In a DESCRIPTION, the value of the name attribute on a wsoap11:fault element MUST match the value of the name attribute on its parent wsdl:fault element. CORE TESTABLE BP2032

4.7.16 Omission of the use Attribute

There is inconsistency between the WSDL 1.1 specification and the WSDL 1.1 schema regarding the use attribute.

R2722 A wsdl:binding in a DESCRIPTION MAY specify the use attribute on contained wsoap11:fault elements. CORE NOT_TESTED

R2723 If in a wsdl:binding in a DESCRIPTION the use attribute on a contained wsoap11:fault element is present, its value MUST be "literal". CORE TESTABLE BP2406

WSDL 1.1 Section 3.6 indicates that the use attribute of wsoap11:fault is required while in the schema the use attribute is defined as optional. The Profile defines it as optional, to be consistent with wsoap11:body .

Since the use attribute is optional, the Profile identifies the default value for the attribute when omitted.

Finally, to assure that the Profile is self-consistent, the only permitted value for the use attribute is "literal".

4.7.17 Default for use Attribute

There is an inconsistency between the WSDL 1.1 specification and the WSDL 1.1 schema regarding whether the use attribute is optional on wsoap11:body , wsoap11:header , and wsoap11:headerfault , and if so, what omitting the attribute means.

R2707 A wsdl:binding in a DESCRIPTION that contains one or more wsoap11:body, wsoap11:fault, wsoap11:header or wsoap11:headerfault elements that do not specify the use attribute MUST be interpreted as though the value "literal" had been specified in each case. CORE NOT_TESTABLE

4.7.18 Consistency of Envelopes with Descriptions

These requirements specify that when an instance receives an envelope that does not conform to the WSDL description, a fault should be generated unless the instance takes it upon itself to process the envelope regardless of this.

As specified by the SOAP processing model, (a) a "VersionMismatch" faultcode must be generated if the namespace of the "Envelope" element is incorrect, (b) a "MustUnderstand" fault must be generated if the instance does not understand a SOAP header block with a value of "1" for the soap11:mustUnderstand attribute. In all other cases where an envelope is inconsistent with its WSDL description, a fault with a "Client" faultcode should be generated.

R2724 If an INSTANCE receives an envelope that is inconsistent with its WSDL description, it SHOULD generate a soap11:Fault with a faultcode of "Client", unless a "MustUnderstand" or "VersionMismatch" fault is generated. CORE NOT_TESTED

R2725 If an INSTANCE receives an envelope that is inconsistent with its WSDL description, it MUST check for "VersionMismatch", "MustUnderstand" and "Client" fault conditions in that order. CORE NOT_TESTABLE

4.7.19 Response Wrappers

WSDL 1.1 Section 3.5 could be interpreted to mean the RPC response wrapper element must be named identical to the name of the wsdl:operation .

R2729 An ENVELOPE described with an rpc-literal binding that is a response MUST have a wrapper element whose name is the corresponding wsdl:operation name suffixed with the string "Response". CORE TESTABLE BP1005

4.7.20 Part Accessors

For rpc-literal envelopes, WSDL 1.1 is not clear what namespace, if any, the accessor elements for parameters and return value are a part of. Different implementations make different choices, leading to interoperability problems.

R2735 An ENVELOPE described with an rpc-literal binding MUST place the part accessor elements for parameters and return value in no namespace. CORE TESTABLE BP1008a BP1008b

R2755 The part accessor elements in a MESSAGE described with an rpc-literal binding MUST have a local name of the same value as the name attribute of the corresponding wsdl:part element. CORE TESTABLE BP1755a BP1755b

Settling on one alternative is crucial to achieving interoperability. The Profile places the part accessor elements in no namespace as doing so is simple, covers all cases, and does not lead to logical inconsistency.

4.7.21 Namespaces for Children of Part Accessors

For rpc-literal envelopes, WSDL 1.1 is not clear on what the correct namespace qualification is for the child elements of the part accessor elements when the corresponding abstract parts are defined to be of types from a different namespace than the targetNamespace of the WSDL description for the abstract parts.

R2737 An ENVELOPE described with an rpc-literal binding MUST namespace qualify the descendents of part accessor elements for the parameters and the return value, as defined by the schema in which the part accessor types are defined. CORE NOT_TESTABLE_XPATH BP1010

WSDL 1.1 Section 3.5 states: "The part names, types and value of the namespace attribute are all inputs to the encoding, although the namespace attribute only applies to content not explicitly defined by the abstract types."

However, it does not explicitly state that the element and attribute content of the abstract (complexType) types is namespace qualified to the targetNamespace in which those elements and attributes were defined. WSDL 1.1 was intended to function in much the same manner as XML Schema. Hence, implementations must follow the same rules as for XML Schema. If a complexType defined in targetNamespace "A" were imported and referenced in an element declaration in a schema with targetNamespace "B", the element and attribute content of the child elements of that complexType would be qualified to namespace "A" and the element would be qualified to namespace "B".

For example,

CORRECT:

Given this WSDL, which defines some schema in the "http://example.org/foo/" namespace in the wsdl:types section contained within a wsdl:definitions that has a targetNamespace attribute with the value "http://example.org/bar/" (thus, having a type declared in one namespace and the containing element defined in another);

<definitions xmlns="http://schemas.xmlsoap.org/wsdl/"
             xmlns:wsoap11="http://schemas.xmlsoap.org/wsdl/soap/"
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             xmlns:bar="http://example.org/bar/"
             targetNamespace="http://example.org/bar/"
             xmlns:foo="http://example.org/foo/">
  <types>
    <xsd:schema targetNamespace="http://example.org/foo/"
                xmlns:tns="http://example.org/foo/"
                xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                elementFormDefault="qualified"
                attributeFormDefault="unqualified">
      <xsd:complexType name="fooType">
        <xsd:sequence>
          <xsd:element ref="tns:bar"/>
          <xsd:element ref="tns:baf"/>
        </xsd:sequence>
      </xsd:complexType>
      <xsd:element name="bar" type="xsd:string"/>
      <xsd:element name="baf" type="xsd:integer"/>
    </xsd:schema>
  </types>

  <message name="BarMsg">
    <part name="BarAccessor" type="foo:fooType"/>
  </message>

  <portType name="BarPortType">
    <operation name="BarOperation">
      <input message="bar:BarMsg"/>
    </operation>
  </portType>

  <binding name="BarSOAP11Binding" type="bar:BarPortType">
    <wsoap11:binding transport="http://schemas.xmlsoap.org/soap/http" style="rpc"/>
    <operation name="BarOperation">
      <input>
        <wsoap11:body use="literal" namespace="http://example.org/bar/"/>
      </input>
    </operation>
  </binding>

  <service name="serviceName">
    <port name="BarSOAPPort" binding="bar:BarSOAP11Binding">
      <wsoap11:address location="http://example.org/myBarSOAPPort"/>
    </port>
  </service>
</definitions>

The resulting envelope for BarOperation is:

<s:Envelope xmlns:soap11="http://schemas.xmlsoap.org/soap/envelope/"
            xmlns:foo="http://example.org/foo/">
  <soap11:Header/>
  <soap11:Body>
    <m:BarOperation xmlns:m="http://example.org/bar/">
      <BarAccessor>
        <foo:bar>String</foo:bar>
        <foo:baf>0</foo:baf>
      </BarAccessor>
    </m:BarOperation>
  </soap11:Body>
</soap11:Envelope>

4.7.22 Required Headers

WSDL 1.1 does not clearly specify whether all wsoap11:header s specified on the wsdl:input or wsdl:output elements of a wsdl:operation element in the SOAP binding section of a WSDL description must be included in the resultant envelopes when they are transmitted. The Profile makes all such headers mandatory, as there is no way in WSDL 1.1 to mark a header optional.

R2738 An ENVELOPE MUST include all wsoap11:headers specified on a wsdl:input or wsdl:output of a wsdl:operation of a wsdl:binding that describes it. CORE TESTABLE BP1009a BP1009b BP1009c

4.7.23 Allowing Undescribed Headers

Headers are SOAP's extensibility mechanism. Headers that are not defined in the WSDL description may need to be included in the envelopes for various reasons.

R2739 An ENVELOPE MAY contain SOAP header blocks that are not described in the wsdl:binding that describes it. CORE NOT_TESTED

R2753 An ENVELOPE containing SOAP header blocks that are not described in the appropriate wsdl:binding MAY have the mustUnderstand attribute on such SOAP header blocks set to '1'. CORE NOT_TESTED

4.7.24 Ordering Headers

There is no correlation between the order of wsoap11:header s in the description and the order of SOAP header blocks in the envelope. Similarly, more than one instance of each specified SOAP header block may occur in the envelope.

R2751 The order of wsoap11:header elements in wsoap11:binding sections of a DESCRIPTION MUST be considered independent of the order of SOAP header blocks in the envelope. CORE NOT_TESTABLE

R2752 An ENVELOPE MAY contain more than one instance of each SOAP header block for each wsoap11:header element in the appropriate child of wsoap11:binding in the corresponding description. CORE NOT_TESTED

4.7.25 Describing SOAPAction

Interoperability testing has demonstrated that requiring the SOAPAction HTTP header field-value to be quoted increases interoperability of implementations. Even though HTTP allows for header field-values to be unquoted, some implementations require that the value be quoted.

The SOAPAction header is purely a hint to processors. All vital information regarding the intent of a message is carried in the envelope.

R2744 If the SOAPAction HTTP header field is present in a MESSAGE, its quoted value MUST be equal to the value of the soapAction attribute of the corresponding wsoap11:operation in the WSDL description, if this attribute is present and not empty. HTTP-TRANSPORT TESTABLE BP1116a BP1116b

R2745 When the wsa:Action header is absent from an ENVELOPE, an HTTP Request MESSAGE MUST contain a SOAPAction HTTP header field with a quoted empty string value if, in the corresponding WSDL description, the soapAction attribute of the wsoap11:operation is either not present, or present with an empty string as its value. HTTP-TRANSPORT TESTABLE

See also R1109 and related requirements for more discussion of SOAPAction.

For example,

CORRECT:

A WSDL Description that has:

<wsoap11:operation soapAction="http://example.org/foo"/>

results in a message with a corresponding SOAPAction HTTP header field as follows:

SOAPAction: "http://example.org/foo"

CORRECT:

A WSDL Description that has:

<wsoap11:operation/>

or

<wsoap11:operation soapAction=""/>

results in a message with a corresponding SOAPAction HTTP header field as follows:

SOAPAction: ""

4.7.26 SOAP Binding Extensions

The wsdl:required attribute has been widely misunderstood and used by WSDL authors sometimes to incorrectly indicate the optionality of wsoap11:header s. The wsdl:required attribute, as specified in WSDL 1.1, is an extensibility mechanism aimed at WSDL processors. It allows new WSDL extension elements to be introduced in a graceful manner. The intent of wsdl:required is to signal to the WSDL processor whether the extension element needs to be recognized and understood by the WSDL processor in order that the WSDL description be correctly processed. It is not meant to signal conditionality or optionality of some construct that is included in the envelopes. For example, a wsdl:required attribute with the value "false" on a wsoap11:header element must not be interpreted to signal to the WSDL processor that the described SOAP header block is conditional or optional in the envelopes generated from the WSDL description. It is meant to be interpreted as "in order to send a envelope to the endpoint that includes in its description the wsoap11:header element, the WSDL processor MUST understand the semantic implied by the wsoap11:header element."

The default value for the wsdl:required attribute for WSDL 1.1 SOAP Binding extension elements is "false". Most WSDL descriptions in practice do not specify the wsdl:required attribute on the SOAP Binding extension elements, which could be interpreted by WSDL processors to mean that the extension elements may be ignored. The Profile requires that all WSDL 1.1 extensions be understood and processed by the consumer, irrespective of the presence or the value of the wsdl:required attribute on an extension element.

R2747 A CONSUMER MUST understand and process all WSDL 1.1 SOAP Binding extension elements, irrespective of the presence or absence of the wsdl:required attribute on an extension element; and irrespective of the value of the wsdl:required attribute, when present. CORE NOT_TESTABLE

R2748 A CONSUMER MUST NOT interpret the presence of the wsdl:required attribute on a wsoap11 extension element with a value of "false" to mean the extension element is optional in the envelopes generated from the WSDL description. CORE NOT_TESTABLE

4.8 Use of XML Schema

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

WSDL 1.1 uses XML Schema as one of its type systems. The Profile mandates the use of XML Schema as the type system for WSDL descriptions of Web Services.

R2800 A DESCRIPTION MAY use any construct from XML Schema 1.0. CORE NOT_TESTED

R2801 A DESCRIPTION MUST use XML Schema 1.0 Recommendation as the basis of user defined datatypes and structures. CORE TESTABLE BP2122

4.9 WS-Addressing 1.0 - Metadata

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

WS-Addressing message addressing properties (MAPs) can be specified in a WSDL document. The Profile adds restrictions to such properties specified in WSDL.

The wsam:Action attribute is used in WSDL to specify the value of the wsa:Action SOAP header in the envelope. A default value computation algorithm is specified for the case where an explicit wsam:Action attribute is not specified. The value of the wsa:Action header in the envelope must match the non-empty value of the SOAPAction HTTP header.

R2900 The value of the wsa:Action header block in an ENVELOPE MUST equal the value (either actual or computed) of the wsam:Action attribute for the corresponding WSDL element (wsdl:input, wsdl:output, or wsdl:fault) contained in the target wsdl:operation of the wsdl:portType. CORE TESTABLE BP1142a BP1142b BP1142c BP1143a BP1143b BP1143c BP1090a BP1090b

R2901 In a DESCRIPTION, the actual value of the wsam:Action attribute for the wsdl:input element contained in the target wsdl:operation of the wsdl:portType MUST be equal to the value of the non-empty soapAction attribute of the wsoap11:operation element contained in the target wsdl:operation of the wsdl:binding. CORE TESTABLE BP2801

5. Service Publication and Discovery

When publication or discovery of Web services is required, UDDI is the mechanism the Profile has adopted to describe Web service providers and the Web services they provide. Business, intended use, and Web service type descriptions are made in UDDI terms; detailed technical descriptions are made in WSDL terms. Where the two specifications define overlapping descriptive data and both forms of description are used, the Profile specifies that the descriptions must not conflict.

Registration of Web service instances in UDDI registries is optional. By no means do all usage scenarios require the kind of metadata and discovery UDDI provides, but where such capability is needed, UDDI is the sanctioned mechanism.

Note that the Web services that constitute UDDI V2 are not fully conformant with the Profile 1.0 because they do not accept messages whose envelopes are encoded in either UTF-8 and UTF-16 as required by the Profile. (They accept UTF-8 only.) That there should be such a discrepancy is hardly surprising given that UDDI V2 was designed and, in many cases, implemented before the Profile was developed. UDDI's designers are aware of UDDI V2's nonconformance and will take it into consideration in their future work.

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

5.1 bindingTemplates

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

UDDI represents Web service instances as uddi:bindingTemplate elements. The uddi:bindingTemplate plays a role that is the rough analog of the wsdl:port , but provides options that are not expressible in WSDL. To keep the WSDL description of an instance and its UDDI description consistent, the Profile places the following constraints on how uddi:bindingTemplate elements may be constructed.

WSDL's wsoap11:address element requires the network address of the instance to be directly specified. In contrast, UDDI V2 provides two alternatives for specifying the network address of instances it represents. One, the uddi:accessPoint , mirrors the WSDL mechanism by directly specifying the address. The other, the uddi:hostingRedirector , provides a Web service-based indirection mechanism for resolving the address, and is inconsistent with the WSDL mechanism.

R3100 REGDATA of type uddi:bindingTemplate representing a conformant INSTANCE MUST contain the uddi:accessPoint element. CORE NOT_TESTED

For example,

INCORRECT:

<bindingTemplate bindingKey="...">
  <description xml:lang="EN">BarSOAPPort</description>
  <hostingRedirector bindingKey="..."/>
  <tModelInstanceDetails>
    ...
  </tModelInstanceDetails>
</bindingTemplate>

CORRECT:

<bindingTemplate bindingKey="...">
  <description xml:lang="EN">BarSOAPPort</description>
  <accessPoint>http://example.org/myBarSOAPPort</accessPoint>
  <tModelInstanceDetails>
    ...
  </tModelInstanceDetails>
</bindingTemplate>

5.2 tModels

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

UDDI represents Web service types as uddi:tModel elements. (See UDDI Data Structures section 8.1.1 .) These may, but need not, point (using a URI) to the document that contains the actual description. Further, UDDI is agnostic with respect to the mechanisms used to describe Web service types. The Profile cannot be agnostic about this because interoperation is very much complicated if Web service types do not have descriptions or if the descriptions can take arbitrary forms.

The UDDI API Specification, appendix I.1.2.1.1 allows but does not require uddi:tModel elements that use WSDL to describe the Web service type they represent to state that they use WSDL as the description language. Not doing so leads to interoperability problems because it is then ambiguous what description language is being used.

Therefore the Profile places the following constraints on how uddi:tModel elements that describe Web service types may be constructed:

The Profile chooses WSDL as the description language because it is by far the most widely used such language.

R3002 REGDATA of type uddi:tModel representing a conformant Web service type MUST use WSDL as the description language. CORE NOT_TESTED

To specify that conformant Web service types use WSDL, the Profile adopts the UDDI categorization for making this assertion.

R3003 REGDATA of type uddi:tModel representing a conformant Web service type MUST be categorized using the uddi:types taxonomy and a categorization of "wsdlSpec". CORE NOT_TESTED

For the uddi:overviewURL in a uddi:tModel to resolve to a wsdl:binding , the Profile must adopt a convention for distinguishing among multiple wsdl:binding s in a WSDL document. The UDDI Best Practice for Using WSDL in a UDDI Registry specifies the most widely recognized such convention.

R3010 REGDATA of type uddi:tModel representing a conformant Web service type MUST follow V1.08 of the UDDI Best Practice for Using WSDL in a UDDI Registry. CORE NOT_TESTED

It would be inconsistent if the wsdl:binding that is referenced by the uddi:tModel does not conform to the Profile.

R3011 The wsdl:binding that is referenced by REGDATA of type uddi:tModel MUST itself conform to the Profile. CORE NOT_TESTED

6. Security

As is true of all network-oriented information technologies, the subject of security is a crucial one for Web services. For Web services, as for other information technologies, security consists of understanding the potential threats an attacker may mount and applying operational, physical, and technological countermeasures to reduce the risk of a successful attack to an acceptable level. Because an "acceptable level of risk" varies hugely depending on the application, and because costs of implementing countermeasures is also highly variable, there can be no universal "right answer" for securing Web services. Choosing the absolutely correct balance of countermeasures and acceptable risk can only be done on a case by case basis.

While Basic Profile conformance is important for the web services community to ensure interoperability, an instance is expected take whatever security countermeasures it deems necessary to protect itself; even if in that specific case it is acting outside of and is not in conformance with this Profile.

There are common patterns of countermeasures that experience shows reduce the risks to acceptable levels for many Web services. The Profile adopts, but does not mandate use of, the most widely used of these: HTTP secured with either TLS 1.0 or SSL 3.0 (HTTPS). That is, conformant Web services may use HTTPS; they may also use other countermeasure technologies or none at all.

HTTPS is widely regarded as a mature standard for encrypted transport connections to provide a basic level of confidentiality. HTTPS thus forms the first and simplest means of achieving some basic security features that are required by many real-world Web service applications. HTTPS may also be used to provide client authentication through the use of client-side certificates.

See conformance criteria in Section 2 when the HTTP(S) transport protocol is used.

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

6.1 Use of HTTPS

HTTPS is such a useful, widely understood basic security mechanism that the Profile needs to allow it.

R5000 An INSTANCE MAY require the use of HTTPS. HTTP-TRANSPORT NOT_TESTED

R5001 If an INSTANCE requires the use of HTTPS, the location attribute of the wsoap11:address element in its wsdl:port description MUST be a URI whose scheme is "https"; otherwise it MUST be a URI whose scheme is "http". HTTP-TRANSPORT NOT_TESTED

Simple HTTPS provides authentication of the Web service instance by the consumer but not authentication of the consumer by the instance. For many instances this leaves the risk too high to permit interoperation. Including the mutual authentication facility of HTTPS in the Profile permits instances to use the countermeasure of authenticating the consumer. In cases in which authentication of the instance by the consumer is insufficient, this often reduces the risk sufficiently to permit interoperation.

R5010 An INSTANCE MAY require the use of HTTPS with mutual authentication. HTTP-TRANSPORT NOT_TESTED

Appendix A: Referenced Specifications

The following specifications' requirements are incorporated into the Profile by reference, except where superseded by the Profile:

Appendix B: Extensibility Points

This section identifies extensibility points, as defined in "Scope of the Profile," for the Profile's component specifications.

These mechanisms are out of the scope of the Profile and Profile conformance. An initial, non-exhaustive list of these extensibility points is provided here as their use may affect interoperability. In order to avoid interoperability issues not addressed by the Profile, out-of-band agreement on the use of these extensibility points may be necessary between the parties to a Web service.

In Simple Object Access Protocol (SOAP) 1.1:

In RFC2616: Hypertext Transfer Protocol -- HTTP/1.1:

In WS-Addressing 1.0 - SOAP Binding (except for sections 2, 3, 5.1.2, 5.2.2 and 6.1):

In XML Schema Part 1: Structures:

In Web Services Description Language (WSDL) 1.1:

In RFC2246: The TLS Protocol Version 1.0:

In The SSL Protocol Version 3.0:

In RFC2459: Internet X.509 Public Key Infrastructure Certificate and CRL Profile:

Appendix C: Normative References

In addition to all of the profiled specifications listed in Appendix A, the following specifications are normatively referenced:

RFC2119 http://ietf.org/rfc/rfc2119 Key words for use in RFCs to Indicate Requirement Levels, S. Bradner March 1997

WS-I Basic Profile 1.1 http://www.ws-i.org/Profiles/BasicProfile-1.1-2006-04-10.html, K. Ballinger et al April 2006

Namespaces in XML 1.0 (Second Edition) http://www.w3.org/TR/REC-xml-names/ T. Bray et al August 2006

WS-I Conformance Claim Attachment Mechanisms Version 1.0 http://www.ws-i.org/Profiles/ConformanceClaims-1.0-2004-11-15.html, M. Nottingham et al November 2004

Appendix D: Defined Terms

The following list of terms have specific definitions that are authoritative for this profile:

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.

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 wsoap11: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 wsoap11:operation element; or
  2. The style attribute is not present on the child wsoap11:operation element, and the wsoap11:binding element in the enclosing wsdl:binding specifies the style attribute with the value "rpc".
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 wsoap11: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 wsoap11:operation element; or
  2. The style attribute is not present on the child wsoap11:operation element, and the wsoap11: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 wsoap11:operation element and the wsoap11:binding element in the enclosing wsdl:binding .
operation signature

The Profile defines the "operation signature" to be the fully qualified name of the child element of SOAP body of the SOAP input message described by an operation in a WSDL binding and the URI value of the wsa:Action SOAP header block, if present.

In the case of rpc-literal binding, the operation name is used as a wrapper for the part accessors. In the document-literal case, since a wrapper with the operation name is not present, the message signatures must be correctly designed so that they meet this requirement.

Appendix E: Acknowledgements

This document is the work of the WS-I Basic Profile Working Group.

Members have included:

Mark Allerton (Crystal Decisions Corp), Steve Anderson (OpenNetwork), George Arriola (Talking Blocks, Inc.), Siddharth Bajaj (Verisign), Keith Ballinger (Microsoft Corp.), David Baum (Kantega AS), Ilya Beyer (KANA), Rich Bonneau (IONA Technologies), Don Box (Microsoft Corp.), Andrew Brown (Verisign), Heidi Buelow (Quovadx), David Burdett (Commerce One, Inc.), Luis Felipe Cabrera (Microsoft Corp.), Maud Cahuzac (France Telecom), Mike Chadwick (Kaiser Permanente), Martin Chapman (Oracle Corporation), Richard Chennault (Kaiser Permanente), Roberto Chinnici (Sun Microsystems), Dipak Chopra (SAP AG), Jamie Clark (OASIS), David Cohen (Merrill Lynch), Ugo Corda (SeeBeyond Tech), Paul Cotton (Microsoft Corp.), Joseph Curran (Accenture), Alex Deacon (Verisign), Mike DeNicola (Fujitsu Limited), Rohit Dewan (Westbridge Technology), Paul Downey (BT Group), Jacques Durand (Fujitsu Limited), Aladin Eajani (Hummingbird, Ltd.), Michael Eder (Nokia), Dave Ehnebuske (IBM), Mark Ericson (Mindreef Inc), Colleen Evans (Microsoft Corp.), Tim Ewald (Microsoft Corp.), Chuck Fay (FileNET Corp.), Leonid Felikson (Freddie Mac), Chris Ferris (IBM), Daniel Foody (Actional Corporation), Satoru Fujita (NEC Corporation), Shishir Garg (France Telecom), Yaron Goland (BEA Systems Inc), Marc Goodner (Microsoft Corp.), Pierre Goyette (Hummingbird, Ltd.), Hans Granqvist (Verisign), Marc Graveline (Cognos), Martin Gudgin (Microsoft Corp.), Arun Gupta (Sun Microsystems), Marc Hadley (Sun Microsystems), Norma Hale (Webify Solutions Inc), Bob Hall (Unisys Corporation), Scott Hanselman (Corillian), Muir Harding (Autodesk Inc.), Loren Hart (Verisign), Andrew Hately (IBM), Harry Holstrom (Accenture), Lawrence Hsiung (Quovadx), Hemant Jain (Tata Consultancy), Steve Jenisch (SAS Institute), Ram Jeyaraman (Microsoft Corp.), Lei Jin (BEA Systems Inc), Erik Johnson (Epicor Software), Bill Jones (Oracle Corporation), Anish Karmarkar (Oracle Corporation), Dana Kaufman (Forum Systems), Takahiro Kawamura (Toshiba), Oldre Kepka (Systinet), Bhushan Khanal (WRQ Inc.), Sandy Khaund (Microsoft Corp.), Doug Kohlert (Sun Microsystems), Jacek Kopecky (Systinet), Vince Kowalski (BMC Software, Inc.), Sanjay Krishnamurthi (Informatica), Sundar Krishnamurthy (Verisign), Eva Kuiper (Hewlett-Packard), Sunil Kunisetty (Oracle Corporation), Christopher Kurt (Microsoft Corp.), Si La (DISA), Lars Laakes (Microsoft Corp.), Charles Lavey (IBM), Canyang Kevin Liu (SAP AG), Ted Liu (webMethods Inc.), Donna Locke (Oracle Corporation), Brad Lund (Intel), Eduardo MacIver (CGI Group), Michael Mahan (Nokia), Ron Marchi (EDS), Jonathan Marsh (Microsoft Corp.), Eric Matland (Hummingbird, Ltd.), Barbara McKee (IBM), Derek Medland (Hummingbird, Ltd.), David Meyer (Plumtree Software Inc.), Jeff Mischkinsky (Oracle Corporation), Ray Modeen (MITRE Corp.), Tom Moog (Sarvega Inc.), Gilles Mousseau (Hummingbird, Ltd.), Greg Mumford (MCI), Jim Murphy (Mindreef Inc), Bryan Murray (Hewlett-Packard), Richard Nikula (BMC Software, Inc.), Eisaku Nishiyama (Hitachi, Ltd.), Mark Nottingham (BEA Systems Inc), David Orchard (BEA Systems Inc), Vivek Pandey (Sun Microsystems), Jesse Pangburn (Quovadx), Mike Parsons (Epicor Software), Eduardo Pelegri-Llopart (Sun Microsystems), Mike Perham (Webify Solutions Inc), Saju Puthankalam (webMethods Inc.), Martin Raepple (SAP AG), Eric Rajkovic (Oracle Corporation), Shaan Razvi (MITRE Corp.), Rimas Rekasius (IBM), Mark Richards (Fidelity), Graeme Riddell (Bowstreet), Ian Robinson (IBM), Sam Ruby (IBM), Tom Rutt (Fujitsu Limited), Saikat Saha (Commerce One, Inc.), Roger Sanborn (Crystal Decisions Corp), Matt Sanchez (Webify Solutions Inc), Krishna Sankar (Cisco Systems Inc.), Jeffrey Schlimmer (Microsoft Corp.), Don Schricker (Micro Focus), Dave Seidel (Mindreef Inc), Darren Self (Micro Focus), AKIRA SHIMAYA (NTT), David Shoaf (Hewlett-Packard), Yasser Shohoud (Microsoft Corp.), David Smiley (Ascential Software), Skip Snow (Citigroup), Seumas Soltysik (IONA Technologies), Joseph Stanko (Plumtree Software Inc.), Andrew Stone (Accenture), Shankaran Subramanian (Citigroup), Julie Surer (MITRE Corp.), YASUO TAKEMOTO (NTT), Nobuyoshi Tanaka (NEC Corporation), Jorgen Thelin (Microsoft Corp.), Sameer Vaidya (Talking Blocks, Inc.), William Vambenepe (Hewlett-Packard), Claus von Riegen (SAP AG), Shrikant Wagh (Hewlett-Packard), Shrikant Wagh (Optimyz), Faisal Waris (Ford Motor Systems), Rick Weil (Eastman Kodak Company), Scott Werden (WRQ Inc.), Ajamu Wesley (IBM), Ian White (Micro Focus), Dave Wilkinson (Vignette), Mark Wood (Eastman Kodak Company), Prasad Yendluri (Software AG), and Brandon Zhu (NetManage Inc).