WS-I

Basic Profile Version 1.1

Board Approval Draft

2004-06-11

This version:
http://www.ws-i.org/Profiles/BasicProfile-1.1-2004-06-11.html
Latest version:
http://www.ws-i.org/Profiles/BasicProfile-1.1.html
Editors:
Keith Ballinger, Microsoft (1.0)
David Ehnebuske, IBM (1.0)
Christopher Ferris, IBM
Martin Gudgin, Microsoft (1.0)
Canyang Kevin Liu, SAP
Mark Nottingham, BEA Systems
Prasad Yendluri, webMethods
Administrative contact:
secretary@ws-i.org

Abstract

This document defines the WS-I Basic Profile 1.1, consisting of a set of non-proprietary Web services specifications, along with clarifications, refinements, interpretations and amplifications of those specifications which promote interoperability

Status of this Document

This document is a Board Approval Draft; it has been approved for publication by the Working Group, and is submitted for consideration by the Board of Directors, and for public comment. It is a work in progress, and should not be considered as final; other documents may supersede this document.

Notice

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

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Table of Contents

1. Introduction
1.1. Relationships to Other Profiles
1.2. Changes from Basic Profile Version 1.0
1.3. Guiding Principles
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. SOAP Envelopes
3.1.1. SOAP Envelope Structure
3.1.2. SOAP Envelope Namespace
3.1.3. SOAP Body Namespace Qualification
3.1.4. Disallowed Constructs
3.1.5. SOAP Trailers
3.1.6. SOAP encodingStyle Attribute
3.1.7. SOAP mustUnderstand Attribute
3.1.8. xsi:type Attributes
3.1.9. SOAP1.1 attributes on SOAP1.1 elements
3.2. SOAP Processing Model
3.2.1. Mandatory Headers
3.2.2. Generating mustUnderstand Faults
3.2.3. SOAP Fault Processing
3.3. SOAP Faults
3.3.1. Identifying SOAP Faults
3.3.2. SOAP Fault Structure
3.3.3. SOAP Fault Namespace Qualification
3.3.4. SOAP Fault Extensibility
3.3.5. SOAP Fault Language
3.3.6. SOAP Custom Fault Codes
3.4. Use of SOAP in HTTP
3.4.1. HTTP Protocol Binding
3.4.2. HTTP Methods and Extensions
3.4.3. SOAPAction HTTP Header
3.4.4. HTTP Success Status Codes
3.4.5. HTTP Redirect Status Codes
3.4.6. HTTP Client Error Status Codes
3.4.7. HTTP Server Error Status Codes
3.4.8. HTTP Cookies
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
4.4. Messages
4.4.1. Bindings and Parts
4.4.2. Bindings and Faults
4.4.3. 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 soapbind 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
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: Defined Terms
Appendix D: Acknowledgements

1. Introduction

This document defines the WS-I Basic Profile 1.1 (hereafter, "Profile"), consisting of a set of non-proprietary Web services specifications, along with clarifications, refinements, interpretations and amplifications of those specifications which promote interoperability.

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

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

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

1.1 Relationships to Other Profiles

This Profile is derived from the Basic Profile 1.0 by incorporating any errata to date and separating out those requirements related to the serialization of envelopes and their representation in messages. Such requirements are now part of the Simple SOAP Binding Profile 1.0, identified with a separate conformance claim. This separation is made to facilitate composability of Basic Profile 1.1 with any profile that specifies envelope serialization, including the Simple SOAP Binding Profile 1.0 and the Attachments Profile 1.0. A combined claim of conformance to both the Basic Profile 1.1 and the Simple SOAP Binding Profile 1.0 is roughly equivalent to a claim of conformance to the Basic Profile 1.0 plus published errata.

This Profile, composed with the Simple SOAP Binding Profile 1.0 supercedes the Basic 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 Changes from Basic Profile Version 1.0

This specification is derived from the Basic Profile Version 1.0, and incorporates published errata against that specification. The most notable changes are:

1.3 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, such testability is not required. Preferably, testing is achieved in a non-intrusive manner (e.g., 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.

1.4 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.

Requirement identifiers 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 by the conformance URI of the document section it occurs in. If it is qualified, the prefix should be interpreted according to the namespace mappings in effect, as documented below.

Some requirements clarify the referenced specification(s), but do not place additional constraints upon implementations. For convenience, clarifications are annotated in the following manner: C

Some requirements are derived from ongoing standardization work on the referenced specification(s). For convenience, such forward-derived statements are annotated in the following manner: xxxx, where "xxxx" is an identifier for the specification (e.g., "WSDL20" for WSDL Version 2.0). Note that because such work was not complete when this document was publiished, the specification that the requirement is derived from may change; this information is included only as a convenience to implementers.

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 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, 1.1). 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 WIDGETs 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; i.e., although this requirement must be met to maintain conformance in most cases, there are some situations where there may be valid reasons for it not being met (which are explained in the requirement itself, or in its accompanying text).

Each requirement statement contains exactly one requirement level keyword (e.g., "MUST") and one conformance target keyword (e.g., "MESSAGE"). Additional text may be included to illuminate a requirement or group of requirements (e.g., rationale and examples); however, prose surrounding requirement statements must not be considered in determining conformance.

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

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

2.2 Conformance Targets

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

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

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

The following conformance targets are used in the Profile:

2.3 Conformance Scope

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

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

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

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

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

2.4 Claiming Conformance

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

The CCAM URI may change before final publication.

  • WSDL 1.1 Claim Attachment Mechanism for Web Services Instances - MESSAGE DESCRIPTION INSTANCE RECEIVER
  • WSDL 1.1 Claim Attachment Mechanism for Description Constructs - DESCRIPTION
  • UDDI Claim Attachment Mechanism for Web Services Instances - MESSAGE DESCRIPTION INSTANCE RECEIVER
  • UDDI Claim Attachment Mechanism for Web Services Registrations - REGDATA
  • The conformance claim URI for this Profile is "http://ws-i.org/profiles/basic/1.1".

    3. Messaging

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

    3.1 SOAP Envelopes

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    SOAP 1.1 defines a structure for composing messages, the envelope. The Profile mandates the use of that structure, and places the following constraints on its use:

    3.1.1 SOAP Envelope Structure

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

    3.1.2 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 soap:Envelope.

    3.1.3 SOAP Body Namespace Qualification

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

    R1014 The children of the soap:Body element in an ENVELOPE MUST be namespace qualified.

    3.1.4 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. C

    R1009 An ENVELOPE MUST NOT contain Processing Instructions. C

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

    R1034 A DESCRIPTION SHOULD NOT contain the namespace declaration xmlns:xml="http://www.w3.org/XML/1998/namespace". C

    3.1.5 SOAP Trailers

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

    R1011 An ENVELOPE MUST NOT have any element children of soap:Envelope following the soap:Body element.

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

    For example,

    INCORRECT:

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

    CORRECT:

    <soap:Envelope xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/' >
      <soap: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>
      </soap:Body>
    </soap:Envelope>

    3.1.6 SOAP encodingStyle Attribute

    The soap: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 soap:encodingStyle attributes on any of the elements whose namespace name is "http://schemas.xmlsoap.org/soap/envelope/".

    R1006 An ENVELOPE MUST NOT contain soap:encodingStyle attributes on any element that is a child of soap:Body.

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

    3.1.7 SOAP mustUnderstand Attribute

    The soap: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 soap:mustUnderstand attribute MUST only use the lexical forms "0" and "1". C

    3.1.8 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 mandate the use of the xsi:type attribute in envelopes except as required in order to indicate a derived type (see XML Schema Part 1: Structures, Section 2.6.1).

    3.1.9 SOAP1.1 attributes on SOAP1.1 elements

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

    3.2 SOAP Processing Model

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    SOAP 1.1 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:

    3.2.1 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 soap:Header element bearing a soap: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. SOAP12

    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.

    3.2.2 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 "soap:MustUnderstand" fault when an envelope contains a mandatory header block (i.e., one that has a soap:mustUnderstand attribute with the value "1") targeted at the receiver (via soap:actor) that the receiver does not understand.SOAP12

    3.2.3 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. SOAP12

    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, a RECEIVER MUST transmit a fault in place of the response. SOAP12

    R1030 A RECEIVER that generates a fault SHOULD notify the end user that a fault has been generated when practical, by whatever means is deemed appropriate to the circumstance. SOAP12

    3.3 SOAP Faults

    3.3.1 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 soap:Body element, that element being a soap:Fault element.

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

    3.3.2 SOAP Fault Structure

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

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

    For example,

    INCORRECT:

    <soap:Fault xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/' >
      <faultcode>soap:Client</faultcode>
      <faultstring>Invalid message format</faultstring>
      <faultactor>http://example.org/someactor</faultactor>
      <detail>There were <b>lots</b> 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>
    </soap:Fault>

    CORRECT:

    <soap:Fault xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/' >
      <faultcode>soap: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 <b>lots</b> of elements in 
             the message that I did not understand
         </m:msg>
         <m:Exception xmlns:m='http://example.org/faults/exceptions'>
           <m:ExceptionType>Severe</m:ExceptionType>
         </m:Exception>
       </detail>
    </soap:Fault>

    3.3.3 SOAP Fault Namespace Qualification

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

    R1001 When an ENVELOPE is a Fault, the element children of the soap:Fault element MUST be unqualified.

    For example,

    INCORRECT:

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

    CORRECT:

    <soap:Fault xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/' 
    			xmlns='' >
      <faultcode>soap: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 <b>lots</b> of elements in the message that 
              I did not understand
          </m:msg>
      </detail>
    </soap:Fault>

    3.3.4 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.

    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/".

    3.3.5 SOAP Fault Language

    Faultstrings are human-readable indications of the nature of a fault. As such, they may not 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://schemas.xmlsoap.org/soap/envelope/2004-01-21.xsd'.

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

    3.3.6 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).

    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.

    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:

    <soap:Fault xmlns:soap='http://schemas.xmlsoap.org/soap/envelope/'
                xmlns:c='http://example.org/faultcodes' >
      <faultcode>soap:Server.ProcessingError</faultcode>
      <faultstring>An error occurred while processing the message
      </faultstring>
    </soap:Fault>

    CORRECT:

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

    CORRECT:

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

    3.4 Use of SOAP in HTTP

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    SOAP 1.1 defines a single protocol binding, for HTTP. The Profile mandates the use of that binding, and places the following constraints on its use:

    3.4.1 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 A MESSAGE MUST be sent using either HTTP/1.1 or HTTP/1.0.

    R1140 A MESSAGE SHOULD be sent using HTTP/1.1.

    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."

    3.4.2 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.

    R1108 A MESSAGE MUST NOT use the HTTP Extension Framework (RFC2774).

    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.

    3.4.3 SOAPAction HTTP Header

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

    SOAPAction is purely a hint to processors. All vital information regarding the intent of a message is carried in soap:Envelope.

    R1109 The value of the SOAPAction HTTP header field in a HTTP request MESSAGE MUST be a quoted string. C

    R1119 A RECEIVER MAY respond with a fault if the value of the SOAPAction HTTP header field in a message is not quoted. C

    R1127 A RECEIVER MUST NOT rely on the value of the SOAPAction HTTP header to correctly process the message.SOAP12

    For example,

    CORRECT:

    A WSDL Description that has:

    <soapbind:operation soapAction="foo" />

    results in a message with a SOAPAction HTTP header field of:

    SOAPAction: "foo"

    CORRECT:

    A WSDL Description that has:

    <soapbind:operation />

    or

    <soapbind:operation soapAction="" />

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

    SOAPAction: ""

    3.4.4 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.

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

    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.

    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.

    3.4.5 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.

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

    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.

    3.4.6 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.

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

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

    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.

    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.

    3.4.7 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.

    3.4.8 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").

    R1122 An INSTANCE using Cookies SHOULD conform to RFC2965.

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

    R1123 The value of the cookie MUST be considered to be opaque by the CONSUMER.

    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).

    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.

    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

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    WSDL 1.1 defines an XML-based structure 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://schemas.xmlsoap.org/wsdl/2003-02-11.xsd".

    R2029 A DESCRIPTION using the WSDL SOAP binding namespace (prefixed "soapbind" in this Profile) MUST be valid according to the XML Schema found at "http://schemas.xmlsoap.org/wsdl/soap/2003-02-11.xsd".

    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.

    Editors' note:The URIs here refer to the corrected schema for BP1.0; they need to be updated before final publication.

    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.

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

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

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

    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".

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

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

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

    For example,

    INCORRECT:

    <definitions name="StockQuote"
       targetNamespace="http://example.com/stockquote/definitions"
       xmlns:xsd1="http://example.com/stockquote/schemas"
               	 ...
       xmlns="http://schemas.xmlsoap.org/wsdl/">
    
       <import namespace="http://example.com/stockquote/schemas"
               location="http://example.com/stockquote/stockquote.xsd"/>
             
       <message name="GetLastTradePriceInput">
            <part name="body" element="xsd1:TradePriceRequest"/>
        </message>
                   ...
    </definitions>

    CORRECT:

    <definitions name="StockQuote"
       targetNamespace="http://example.com/stockquote/definitions"
               	 ...
       xmlns="http://schemas.xmlsoap.org/wsdl/">
       
       <import namespace="http://example.com/stockquote/definitions"
               location="http://example.com/stockquote/stockquote.wsdl"/>
               
       <message name="GetLastTradePriceInput">
          <part name="body" element="..."/>
       </message>
                      ...
       </definitions>

    CORRECT:

    <definitions name="StockQuote"  
       targetNamespace="http://example.com/stockquote/"
       xmlns:xsd1="http://example.com/stockquote/schemas"
               	 ...
       xmlns="http://schemas.xmlsoap.org/wsdl/">
       
       <import namespace="http://example.com/stockquote/definitions"
            location="http://example.com/stockquote/stockquote.wsdl"/>
               
       <message name="GetLastTradePriceInput">
          <part name="body" element="xsd1: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.

    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. C

    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.

    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.

    For example,

    INCORRECT:

    <definitions name="StockQuote"  
               	 ...
       xmlns="http://schemas.xmlsoap.org/wsdl/">
       
       <import namespace="http://example.com/stockquote/definitions"
             location="http://example.com/stockquote/stockquote.wsdl"/>
               
       <message name="GetLastTradePriceInput">
           <part name="body" type="tns:TradePriceRequest"/>
       </message>
                   ...
       <service name="StockQuoteService">
          <port name="StockQuotePort" binding="tns:StockQuoteSoap">
               ....
          </port>
       </service>
    
       <types>
          <schema targetNamespace="http://example.com/stockquote/schemas"
                   xmlns="http://www.w3.org/2001/XMLSchema">
               .......
          </schema>
       </types>
    </definitions>

    CORRECT:

       <definitions name="StockQuote"
          targetNamespace="http://example.com/stockquote/definitions">
    
         <import namespace="http://example.com/stockquote/base"
           location="http://example.com/stockquote/stockquote.wsdl"/>
            
          <message name="GetLastTradePriceInput">
             <part name="body" element="..."/>
          </message>
                      ...
       </definitions>

    CORRECT:

    <definitions name="StockQuote"  
               	 ...
       xmlns="http://schemas.xmlsoap.org/wsdl/">
    
      <types>
         <schema targetNamespace="http://example.com/stockquote/schemas"
              xmlns="http://www.w3.org/2001/XMLSchema">
               .......
         </schema>
       </types>
               
       <message name="GetLastTradePriceInput">
            <part name="body" element="tns: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.

    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".C

    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).C

    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.

    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.

    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 WSDL1.1 specification.WSDL20

    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.

    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.

    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.

    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 WSDL1.1 schema that reflects this capability at: http://ws-i.org/profiles/basic/1.1/wsdl11.xsd

    Editors' note:The schema needs to be updated to reflect element and attribute extensibility, as per SWA124.

    4.3 Types

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    The wsdl:types element of WSDL 1.1 encloses 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.

    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.

    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).

    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.

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

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

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

    For example,

    INCORRECT:

    Given the WSDL Description:

    <xsd:element name="MyArray2" type="tns:MyArray2Type"/>
    <xsd:complexType name="MyArray2Type" 
     xmlns:soapenc="http://schemas.xmlsoap.org/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.WSDL20

    4.4 Messages

    The following specifications (or sections thereof) are referred to in this section of the Profile;

    In WSDL 1.1, wsdl:message elements 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 soapbind: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 soapbind:operation element; or
    2. The style attribute is not present on the child soapbind:operation element, and the soapbind: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 soapbind: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 soapbind:operation element; or
    2. The style attribute is not present on the child soapbind:operation element, and the soapbind: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 soapbind:operation element and the soapbind: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 soapbind:body element(s), have at most one part listed in the parts attribute, if the parts attribute is specified.

    R2209 A wsdl:binding in a DESCRIPTION SHOULD bind every wsdl:part of a wsdl:message in the wsdl:portType to which it refers with a binding extension element.

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

    R2202 A wsdl:binding in a DESCRIPTION MAY contain soapbind:body element(s) that specify that zero parts form the soap:Body.

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

    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.

    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 soapbind:body in an rpc-literal binding.

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

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

    R2212 An ENVELOPE MUST contain exactly one part accessor element for each of the wsdl:part elements bound to the envelope's corresponding soapbind:body element.

    R2213 In a doc-literal description where the value of the parts attribute of soapbind:body is an empty string, the corresponding ENVELOPE MUST have no element content in the soap:Body element.

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

    Use of wsdl:message elements with zero parts is permitted in Document styles to permit operations that can send or receive envelopes with empty soap:Bodys. 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 soap: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 soapbind:fault, soapbind:header, and soapbind:headerfault may be defined.

    R2205 A wsdl:binding in a DESCRIPTION MUST refer, in each of its soapbind:header, soapbind:headerfault and soapbind:fault elements, only to