Web Services Description Language (WSDL) Version 1.2 Part 1: Core Language

2.1.1 The Definitions Component

At the abstract level, the Definitions component is just a container for two categories of component; WSDL components and type system components.

WSDL components are interfaces, bindings and services.

Type system components are element declarations and type definitions drawn from some type system. The former define the [local name], [namespace name], [children] and [attributes] properties of an element information item; the latter define only the [children] and [attributes] properties.

The properties of the Definitions component are as follows:

• {interfaces} A set of named interface definitions

• {bindings} A set of named binding definitions

• {services} A set of named service definitions

• {type definitions} A set of named type definitions, each one isomorphic to a simple or complex type as defined by XML Schema

• {element declarations} A set of named element declarations, each one isomorphic to a global element declaration as defined by XML Schema

The set of interfaces/binding/services/etc. available in the Definitions component include those that are defined within the component itself and those that are imported and/or included. At the component model level, there is no distinction between directly defined components vs. imported/included components.

The components directly defined within a single Definitions component are said to belong to the same target namespace. The target namespace therefore groups a set of related component definitions and provides a hint of the intended semantics of the components.

Imported components have different target namespace values from the Definitions component that is importing them. Thus importing is the mechanism to use components from one namespace in another set of definitions.

Each WSDL or type/element component MUST be uniquely identified by its qualified name. That is, if two distinct components of the same kind (Interface, Binding etc.) are in the same target namespace, then their QNames MUST be unique. However, different kids of components (e.g., an Interface component and a Binding component) MAY have the same QName. Thus, QNames of components must be unique within the space of those components in a given target namespace.

In addition to WSDL components and type and element components, additional extension components MAY be added via extensibility 6. Language Extensibility. Further, additional properties to WSDL and type/element components MAY also be added via extensibility.

2.1.2 XML Representation of Definitions Component

<definitions
      targetNamespace="xs:anyURI" >
  <documentation />?
  [ <import /> | <include /> ]*
  <types />?
  [ <interface /> | <binding /> | <service /> ]*
</definitions>

WSDL definitions are represented in XML by one or more WSDL Information Sets (Infosets), that is one or more definitions element information items. A WSDL Infoset contains representations for a collection of WSDL components which share a common target namespace. A WSDL Infoset which contains one or more import element information items 4.2 Importing Descriptions corresponds to a collection with components drawn from multiple target namespaces.

The target namespace represents an unambiguous name for the intended semantics of the WSDL Infoset. The targetNamespace URI SHOULD point to a human or machine processable document that directly or indirectly defines the semantics of the WSDL Infoset.

The definitions element information item has the following Infoset properties:

• A [local name] of definitions .

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl".

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED targetNamespace attribute information item as described below in 2.1.2.1 targetNamespace attribute information item.

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more element information items from among the following, in any order:

     • Zero or more include element information items (see 4.1 Including Descriptions)

     • Zero or more import element information items (see 4.2 Importing Descriptions)

     • Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

  3. An OPTIONAL types element information item (see 3. Types).

  4. Zero or more element information items from among the following, in any order:

     • interface element information items (see 2.2.2 XML Representation of Interface Component).

     • binding element information items (see 2.8.2 XML Representation of Binding Component).

     • service element information items (see 2.12.2 XML Representation of Service Component).

     • Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

2.1.3 Mapping Definitions' XML Representation to Component Properties

The mapping between the properties of the Definitions component (see 2.1.1 The Definitions Component) and the XML Representation of the definitions element information item (see 2.1.2 XML Representation of Definitions Component) is described in Table 2-1.

2.2.1 The Interface Component

An Interface component describes sets of messages that a service sends and/or receives. It does this by grouping related messages into operations. An operation is a set of input and output messages, an interface is a set of operations.

An interface can optionally extend one or more other interfaces. In such cases the interface contains the operations of the interfaces it extends, along with any operations it defines. The interfaces a given interface extends MUST NOT themselves extend that interface either directly or indirectly.

Interfaces are named constructs and can be referred to by QName (see 2.16 QName resolution). For instance, Binding components refer to interfaces in this way.

The properties of the Interface component are as follows:

• {name} An NCName as defined by [XML Namespaces].

• {target namespace} A namespace name, as defined in [XML Namespaces].

• {extended interfaces} A set of named interface definitions which this interface extends.

• {style default} The default style of message schemas of the operations. If a per-operation value is not specified for this property, then this value becomes the default value of the property. See 2.3.2.3 style attribute information item with operation [owner]

• {operations} A set of named interface operation definitions.

• {features} A set of named feature definitions.

• {properties} A set of named property definitions.

For each Interface component in the {interfaces} property of a definitions container the combination of {name} and {target namespace} properties must be unique.

2.2.2 XML Representation of Interface Component

<definitions>
  <interface
        name="xs:NCName" 
        extends="list of xs:QName"?
        styleDefault="xs:anyURI"? >
    <documentation />?
    [ <operation /> | <feature /> | <property /> ]*
  </interface>
</definitions>

The XML representation for an Interface component is an element information item with the following Infoset properties:

• A [local name] of interface

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED name attribute information item as described below in 2.2.2.1 name attribute information item with interface [owner].

  • An OPTIONAL extends attribute information item as described below in 2.2.2.2 extends attribute information item.

  • An OPTIONAL styleDefault attribute information item as described below in 2.2.2.3 styleDefault attribute information item.

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more element information items from among the following, in any order:

     • Zero or more operation element information items 2.3.2 XML Representation of Interface Operation Component.

     • Zero or more feature element information items 2.6.2 XML Representation of Feature Component.

     • Zero or more property element information items 2.7.2 XML Representation of Property Component.

     • Zero or more namespace-qualified element information items amongst its [children]. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

2.2.3 Mapping Interface's XML Representation to Component Properties

The mapping between the properties of the Interface component (see 2.2.1 The Interface Component) and the XML Representation of the interface element information item (see 2.2.2 XML Representation of Interface Component) is as described in Table 2-2.

2.3.1 The Interface Operation Component

An Interface Operation component describes an operation that a given interface supports. An operation is an interaction with the service consisting of a set (ordinary and fault) messages exchanged between the service and the other roles involved in the interaction, in particular the service requestor. The sequencing and cardinality of the messages involved in a particular interaction is governed by the message exchange pattern used by the operation (see {message exchange pattern} property).

A message exchange pattern defines placeholders for messages, the participants in the pattern (i.e., the sources and sinks of the messages), and the cardinality and sequencing of messages exchanged by the participants. The message placeholders are associated with specific message types by the operation using the pattern via message and fault references (see {message references} and {fault references} properties). The service whose operation is using the pattern becomes one of the participants of the pattern. This specification does not define a machine understandable language for defining message exchange patterns nor does it define any specific patterns. The companion specification, [WSDL 1.2 Message Exchange Patterns] defines a set of such patterns and defines identifying URIs any of which MAY be used as the value of the {message exchange pattern} property.

The properties of the Interface Operation component are as follows:

• {name} An NCName as defined by [XML Namespaces].

• {target namespace} A namespace name, as defined in [XML Namespaces].

• {message exchange pattern} A URI identifying the message exchange pattern used by the operation.

• {message references} A set of Message Reference components for the ordinary messages the operation accepts or sends. (See 2.4 Message Reference.)

• {fault references} A set of Fault Reference components for the fault messages the operation accepts or sends. (See 2.5 Fault Reference.)

• {style} A URI identifying the rules that were used to construct the {body} properties of {message references}. (See 2.3.1.1 Operation Style

• {features} A set of named feature definitions used by the operation

• {properties} A set of named property definitions used by the operation

Interface Operation components are local to Interface components; they cannot be referred to by QName, despite having both {name} and {target namespace} properties. That is, this specification does not preclude one from having two distinct Interface Operation components which have the same {name} and {target namespace} properties, as long as they are in different Interface components (with the same {target namespace} property).

For each Interface Operation component in the {operations} property of an Interface component the combination of {name} and {target namespace} properties must be unique.

In cases where, due to an interface extending one or more other interfaces, two or more Interface Operation components have the same value for their {name} and {target namespace} properties, then the component models of those Interface Operation components MUST be equivalent (see 2.14 Equivalence of Components). If the Interface Operation components are equivalent then they are considered to collapse into a single component. It is an error if two Interface Operation components have the same value for their {name} and {target namespace} properties but are not equivalent.

2.3.2 XML Representation of Interface Operation Component

<definitions>
  <interface>
    <operation
          name="xs:NCName" 
          pattern="xs:anyURI"
          style="xs:anyURI"? >
      <documentation />?
      [ <feature /> | <property /> | 
        [ <input /> | <output /> | <infault /> | <outfault /> ]+
      ]*
    </operation>
  </interface>
</definitions>

The XML representation for an Interface Operation component is an element information item with the following Infoset properties:

• A [local name] of operation

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• Two or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED name attribute information item as described below in 2.3.2.1 name attribute information item with operation [owner].

  • A REQUIRED pattern attribute information item as described below in 2.3.2.2 pattern attribute information item with operation [owner].

  • An OPTIONAL style attribute information item as described below in 2.3.2.3 style attribute information item with operation [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• One or more element information item amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more element information items from among the following, in any order:

     • Zero or more input element information items (see 2.4.2 XML Representation of Message Reference Component).

     • Zero or more output element information items (see 2.4.2 XML Representation of Message Reference Component).

     • Zero or more infault element information items (see 2.5.2 XML Representation of Fault Reference Component).

     • Zero or more outfault element information items (see 2.5.2 XML Representation of Fault Reference Component).

     • A feature element information item (see 2.6.2 XML Representation of Feature Component).

     • A property element information item (see 2.7.2 XML Representation of Property Component).

     • Zero or more namespace-qualified element information items amongst its [children]. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• At least one of the [children] MUST be an input , output , infault , or outfault element information item.

2.3.3 Mapping Interface Operation's XML Representation to Component Properties

The mapping between the properties of the Interface Operation component (see 2.3.1 The Interface Operation Component) and the XML Representation of the interface element information item (see 2.3.2 XML Representation of Interface Operation Component) is as described in Table 2-3.

2.4.1 The Message Reference Component

A Message Reference component associates XML element declarations that define the message body and headers for one of the messages participating in an operation.

Message Reference components are identified by the role the message plays in the {message exchange pattern} that the operation is using. That is, a message exchange pattern defines a set of placeholder messages that participate in the pattern and assigns them unique names within the pattern. The purpose of a Message Reference component is to associate an actual message type (XML element declarations for message body and headers) for the message that will perform a specific role in the message exchange pattern.

The properties of the Message Reference component are as follows:

• {message reference} An NCName as defined by [XML Namespaces]. This property identifies the role this message plays in the {message exchange pattern} of the Interface Operation component this is contained within. The value of this property MUST match the name of a placeholder message defined by the message exchange pattern.

• {direction} One of in or out indicating whether the message is coming to the service or going from the service, respectively. The direction MUST be the same as the direction of the message identified by the {message reference} property in the {message exchange pattern} of the Interface Operation component this is contained within.

• {body} A reference to an XML element declaration. This element represents the "payload" of the message.

• {headers} A list of references to XML element declarations. Each of these elements represents a "header" of the message.

For each Message Reference component in the {message references} property of an Interface Operation component the {message reference} property MUST be unique.

2.4.2 XML Representation of Message Reference Component

<definitions>
  <interface>
    <operation>
      <input
            messageReference="xs:NCName"? 
            body="xs:QName"?
            headers="list of xs:QName"? >
        <documentation />?
      </input>
      <output
            messageReference="xs:NCName"?
            body="xs:QName"?
            headers="list of xs:QName"? >
        <documentation />?
      </output>
    </operation>
  </interface>
</definitions>

The XML representation for a Message Reference component is an element information item with the following Infoset properties:

• A [local name] of input or output

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• Zero or more attribute information items amongst its [attributes] as follows:

  • An OPTIONAL messageReference attribute information item as described below in 2.4.2.1 messageReference attribute information item with input, or output [owner].

  • An OPTIONAL body attribute information item as described below in 2.4.2.2 body attribute information item with input, or output [owner].

  • An OPTIONAL headers attribute information item as described below in 2.4.2.3 headers attribute information item with input, or output [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

2.4.3 Mapping Message Reference's XML Representation to Component Properties

The mapping between the properties of the Message Reference component (see 2.4.1 The Message Reference Component) and the XML Representation of the message reference element information item (see 2.4.2 XML Representation of Message Reference Component) is as described in Table 2-4.

2.5.1 The Fault Reference Component

A Fault Reference component associates an XML element declaration that defines the fault message contents for a fault that occurs related to a message participating in an operation.

Fault Reference components are identified by the role the related message plays in the {message exchange pattern} that the operation is using. That is, a message exchange pattern defines a set of placeholder messages that participate in the pattern and assigns them unique names within the pattern. The purpose of a Fault Reference component is to associate an actual message type (XML element declaration) for the fault that will occur related to a specific role in the message exchange pattern.

The companion specification [WSDL 1.2 Message Exchange Patterns] defines two fault patterns that a given message exchange pattern may use. For the pattern fault-replaces-message, the message that the fault relates to identifies the message in place of which the declared fault message will occur. For the pattern message-triggers-fault, the message that the fault relates to identifies the message after which the indicated fault may occur, in the opposite direction of the referred to message.

More than one Fault Reference component may refer to the same message role. This allows one to indicate that there are more than one faults that are related to that message.

The properties of the Fault Reference component are as follows:

• {message reference} An NCName as defined by [XML Namespaces]. This property identifies the message which this fault relates to in the {message exchange pattern} of the Interface Operation component this is contained within. The value of this property MUST match the name of a placeholder message defined by the message exchange pattern.

• {direction} One of in or out indicating whether the message is coming to the service or going from the service, respectively. The direction MUST be the same as the direction of the message identified by the {message reference} property in the {message exchange pattern} of the Interface Operation component this is contained within.

• {details} A reference to an XML element declaration. This element represents the "payload" of the fault.

For each Fault Reference component in the {fault references} property of an Interface Operation component the pair {message reference} and {details} properties MUST be unique. That is, there cannot be two or more Fault Reference components which have the same {message reference} and {details} properties.

2.5.2 XML Representation of Fault Reference Component

<definitions>
  <interface>
    <operation>
      <infault
            messageReference="xs:NCName"
            details="xs:QName"
        <documentation />?
      </infault>*
      <outfault
            messageReference="xs:NCName"
            details="xs:QName"
        <documentation />?
      </outfault>*
    </operation>
  </interface>
</definitions>

The XML representation for a Fault Reference component is an element information item with the following Infoset properties:

• A [local name] of infault or outfault

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• Zero or more attribute information items amongst its [attributes] as follows:

  • An REQUIRED messageReference attribute information item as described below in 2.5.2.1 messageReference attribute information item with infault, or outfault [owner].

  • An REQUIRED details attribute information item as described below in 2.5.2.2 details attribute information item with infault, or outfault [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

2.5.3 Mapping Fault Reference's XML Representation to Component Properties

The mapping between the properties of the Fault Reference component (see 2.5.1 The Fault Reference Component) and the XML Representation of the message reference element information item (see 2.5.2 XML Representation of Fault Reference Component) is as described in Table 2-5.

2.6.1 The Feature Component

A feature component describes an abstract piece of functionality typically associated with the exchange of messages between communicating parties. Although WSDL poses no constraints on the potential scope of such features, examples might include "reliability", "security", "correlation", and "routing". The presence of a feature component in a WSDL description indicates that the feature is either accepted or required in particular interactions.

Features in the Feature component are identified by their URI. Unless otherwise specified, recognizing a feature's URI is assumed to be semantically equivalent to understanding the feature's specification.

The properties of the Feature component are as follows:

• {name} A URI as defined by [IETF RFC 2396].

• {required} A boolean value.

2.6.2 XML Representation of Feature Component

<feature
      uri="xs:QName" 
      required="xs:boolean"? >
  <documentation />?
</feature>

The XML representation for a Feature component is an element information item with the following Infoset properties:

• A [local name] of feature

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED uri attribute information item as described below in 2.6.2.1 uri attribute information item with feature [owner].

  • An OPTIONAL required attribute information item as described below in 2.6.2.2 required attribute information item with feature [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

2.6.3 Mapping Feature's XML Representation to Component Properties

The mapping between the properties of the Feature component (see 2.6.1 The Feature Component) and the XML Representation of the feature element information item (see 2.6.2 XML Representation of Feature Component) is as described in Table 2-6.

2.7.1 The Property Component

A Property component describes the set of possible values for a particular property. The permissible values are specified by references to a Schema description. A property is typically used to control a feature's behavior. Properties, and hence property values, can be shared amongst features.

The properties of the Property component are as follows:

• {name} A URI as defined by [IETF RFC 2396].

• {required} A boolean value.

• {value constraint} A type definition constraining the value of the property.

2.7.2 XML Representation of Property Component

<property
      uri="xs:QName" 
      required="xs:boolean"? >
  <documentation />?
  [ <value /> | <constraint /> ]
</property>

The XML representation for a Property component is an element information item with the following Infoset properties:

• A [local name] of property

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED uri attribute information item as described below in 2.7.2.1 uri attribute information item with property [owner].

  • An OPTIONAL required attribute information item as described below in 2.7.2.2 required attribute information item with feature [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• One or more element information items amongst its [children], in order as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. One REQUIRED element information item from among the following:

     • A value element information item as described in 2.7.2.3 value element information item with property [parent]

     • A constraint element information item as described in 2.7.2.4 constraint element information item with property [parent]

  3. Zero or more namespace-qualified element information items amongst its [children]. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

<property>
  <value>
    xs:anySimpleType
  </value>
</property>

<property>
  <constraint>
    xs:QName
  </constraint>
</property>

2.7.3 Mapping Property's XML Representation to Component Properties

The mapping between the properties of the Property component (see 2.7.1 The Property Component) and the XML Representation of the property element information item (see 2.7.2 XML Representation of Property Component) is as described in Table 2-7.

2.8.1 The Binding Component

A Binding component describes a concrete message format and transmission protocol which may be used to define an endpoint (see 2.13 Endpoint). Binding components can be used to describe such information in a re-usable manner for any interface or specifically for a given interface. Furthermore, binding information MAY be specified on a per-operation basis (see 2.9.1 The Binding Operation Component) within an interface in addition to across all operations of an interface.

If a Binding component specifies operation-specific binding details (by including Binding Operation components) then it MUST specify an interface the Binding component applies to to indicate which interface the operations come from.

Conversely, a Binding component MAY omit any operation-specific binding details and MAY omit specifying an interface. Binding components that do not specify an interface MAY be used to specify operation-independent binding details for Service components with different interfaces.

No concrete binding details are given in this specification. The companion specification, WSDL (Version 1.2): Bindings [WSDL 1.2 Bindings] defines such bindings for SOAP 1.2 [SOAP 1.2 Part 1: Messaging Framework], HTTP [IETF RFC 2616] and MIME [IETF RFC 2045]. Other specifications MAY define additional binding details. Such specifications are expected to annotate the Binding component (and its sub-components) with additional properties and specify the mapping between those properties and the XML representation.

Bindings are named constructs and can be referred to by QName (see 2.16 QName resolution). For instance, Endpoint components refer to bindings in this way.

The properties of the Binding component are as follows:

• {name} An NCName as defined by [XML Namespaces].

• {target namespace} A namespace name, as defined in [XML Namespaces].

• {interface} An named interface definition indicating the interface for which binding information is being specified.

• {operations} A set of named binding operation definitions

• {features} A set of named feature definitions

• {properties} A set of named property definitions

For each Binding component in the {bindings} property of a definitions container, the combination of {name} and {target namespace} properties must be unique.

2.8.2 XML Representation of Binding Component

<definitions>
  <binding
        name="xs:NCName" 
        interface="xs:QName"? >
    <documentation />?
    [ <feature /> | <property /> | <operation /> ]*
  </binding>
</definitions>

The XML representation for a Binding component is an element information item with the following Infoset properties:

• A [local name] of binding

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED name attribute information item as described below in 2.8.2.1 name attribute information item with binding [owner].

  • An OPTIONAL interface attribute information item as described below in 2.8.2.2 interface attribute information item with binding [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more element information items from among the following, in any order:

     • Zero or more operation element information items (see 2.9.2 XML Representation of Binding Operation Component).

     • Zero or more feature element information items (see 2.6.2 XML Representation of Feature Component).

     • Zero or more property element information items (see 2.7.2 XML Representation of Property Component).

     • Zero or more namespace-qualified element information items. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl". Such element information items are considered to be binding extension elements(see 2.8.2.3 Binding extension elements).

2.8.3 Mapping Binding's XML Representation to Component Properties

The mapping between the properties of the Binding component (see 2.8.1 The Binding Component) and the XML Representation of the binding element information item (see 2.8.2 XML Representation of Binding Component) is as described in Table 2-8.

2.9.1 The Binding Operation Component

A Binding Operation component describes a concrete binding for a particular operation of an interface to a particular concrete message format. A particular operation of an interface is uniquely identified by the target namespace of the interface and the name of the operation within that interface.

The properties of the Binding Operation component are as follows:

• {name} An NCName as defined by [XML Namespaces].

• {target namespace} A namespace name, as defined in [XML Namespaces].

• {message references} A set of Binding Message Reference components

• {fault references} A set of Binding Fault Reference components

The tuple of properties {name} and {target namespace} identify the operation for which binding information is being specified.

For each Binding Operation component in the {operations} property of a Binding component the combination of {name} and {target namespace} properties must be unique. That is, one cannot define multiple bindings for the same operation.

2.9.2 XML Representation of Binding Operation Component

<definitions>
  <binding>
    <operation
          name="xs:QName" >
      <documentation />?
      [ <feature /> | <property /> | 
        [ <input /> | <output /> | <infault /> | <outfault /> ]+
      ]*
    </operation>
  </binding>
</definitions>

The XML representation for a Binding Operation component is an element information item with the following Infoset properties:

• A [local name] of operation

• A [namespace name] of "http://www.w3.org/@@@@/@@/wsdl"

• One or more attribute information items amongst its [attributes] as follows:

  • A REQUIRED name attribute information item as described below in 2.9.2.1 name attribute information item with operation [owner].

  • Zero or more namespace qualified attribute information items. The [namespace name] of such attribute information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl".

• Zero or more element information items amongst its [children], in order, as follows:

  1. An OPTIONAL documentation element information item (see 5. Documentation).

  2. Zero or more element information items from among the following, in any order:

     • Zero or more input element information items (see 2.10 Binding Message Reference )

     • Zero or more output element information items (see 2.10 Binding Message Reference )

     • Zero or more infault element information items (see 2.10 Binding Message Reference )

     • Zero or more outfault element information items (see 2.10 Binding Message Reference )

     • Zero or more feature element information items

     • Zero or more property element information items

     • Zero or more namespace-qualified element information items amongst its [children]. The [namespace name] of such element information items MUST NOT be "http://www.w3.org/@@@@/@@/wsdl". Such element information items are considered to be binding operation extension elements as described below (see 2.9.2.2 Binding Operation extension elements).

2.9.3 Mapping Binding Operation's XML Representation to Component Properties

The mapping between the properties of the Binding Operation component (see 2.9.1 The Binding Operation Component) and the XML Representation of the binding element information item (see 2.9.2 XML Representation of Binding Operation Component) is as described in Table 2-9.

2.10.1 The Binding Message Reference Component

A Binding Message Reference component describes a concrete binding for a particular message participating in an operation to a particular concrete message format.

The properties of the Binding Message Reference component are as follows:

• {message reference} An NCName as defined by [XML Namespaces]. The value of this property identifies the message within the operation for which binding details are being specified.

• {direction} One of in or out indicating whether the message is coming to the service or going from the service, respectively.

For each Binding Message Reference component in the {message references} property of a Binding Operation component the {message reference} property must be unique. That is, the same message cannot be bound twice within the same operation.

2.10.2 XML Representation of Binding Message Reference Component

<definitions>
  <binding>
    <operation>
      <input
            messageReference="xs:NCName" >
        <documentation />?
      </input>
      <output
            messageReference="xs:NCName" >
        <documentation />?
      </output>
    </operation>
  </binding>
</definitions>

The XML representation for a Binding Message Reference component is an element information item with the following Infoset properties:

• A [local name] of input or output .

• A [namespace nam