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Subject: Re: [wsrm] Rel49
The RM- agreement text for the mesage expiry and group expiry client configuration parameters should be used. It already explains it as a duration. thus, I propose that in the two subsections for messageExpiry time and group Expiry time, in the ws-reliabiliy portion of your proposal: change: " The type of this property is xs:dateTime. [[ Note: In most client-side deployments it is expected that wsrm:group-expiry-time would be defined as something like "Now + duration", rather than an absolute date/time (which would be translated into an absolute date/time for every group). From that perspective it might be worthwhile to define this property as xs:duration OR keep it untyped. ]] " To "They type of this property is xs:duration. Note: The expiry time is calculated at the time a message is sent, by adding this duration to the time the message is sent. " Anish Karmarkar wrote: > Attached is the modified version of my original proposal. > > The change from the original proposal is: > > 1) Replaced "http://www.ws-standards.org/fnp/"; > with "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/"; > > 2) Replaced "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/"; > with "http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > > As before, the proposal consists of two parts: > 1) FnPwsdl11-version2.txt -- this is a backport of the WSDL 2.0 > Features and Property framework [2] to WSDL 1.1. > 2) ws-reliability-fnp.txt -- this contains definition of > ws-reliability specific features and properties. > > I hope this addresses the concern regarding having a non-wsrm namespace. > > If you prefer to have different namespaces than what is proposed, > please let me know. > > Thanks! > > -Anish > -- > > iwasa wrote: > >> Anish and all, >> >> Since we have short time remaining before >> WS-I F2F meeting, we must close Rel49 by the telecon next week with >> concrete proposal with text to be incorporated in the spec. >> >> *And* if we can not agree the resolution by that time, >> I would propose we do not include anything >> in the spec for Rel49 and close the issue with no action. >> >> I do not agree to spend additional one more week when >> we can't close the issue by the next telecon. >> >> So I would propose Anish to send out proposal >> ASAP (by the end of this week at latest, I would suggest) to discuss >> and agree with the proposal before the telecon, if you really need >> your proposal accepted. Otherwise there >> would be chance of running out of time. >> >> I hope we resolve issue49 before the next telecon. >> >> Thanks, >> >> Iwasa >> > >------------------------------------------------------------------------ > >Proposal for Adding Compositors, Features and Properties to WS-Reliability >-------------------------------------------------------------------- > >[[ Note: This proposal is the WSDL 1.1 analogue of the proposal [1] that is >currently under discussion in WSD WG. Also note that WSDL 2.0 component >model defines features and properties, whereas WSDL 1.1 does not. ]] > >I. Introduction > >It is necessary for WS-Reliability to advertise its capabilities in >the description of services. This allows clients (or other Web >services) to obtain information about specific capabilities such as >guaranteed delivery, duplicate elimination, message ordering, and various >reply patterns of a specific Web service and "invoke" it. Given that the >description of the service is available in a WSDL document, such capability >assertions need be in the same document. Therefore there is a need for a >standard extensible framework for tagging Web services with capability >assertions. > >This proposal uses the WSDL 1.1 extensibility points to define an extensible >framework consisting of features, properties and compositors to address >the needs of a reliable Web services to advertise its capabilities, and >composability of those capabilities. > >This proposal defines the following extensibility elements and the semantics >associated with them that forms an extensible framework: > > * feature - abstract functionality associated with WSDL elements. > * property - value or value constraint associated with WSDL elements. > * compositor - specify how features and properties are combined. > >This extensible framework would allow, for example, a Web service description >to advertise the fact that clients invoking the service must authenticate >itself using X.509 token, or kerberos token or username token. > >I.A Notational Convention > >This specification uses the following namespace prefixes: > > Prefix Namespace > ------ --------- > xs "http://www.w3.org/2001/XMLSchema"; > wsdl11 "http://schemas.xmlsoap.org/wsdl/"; > fnp "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/"; > >The choice of any namespace prefix is arbitrary and not semantically >significant. > >I.B Conformance > >Implementations of WS-Reliability are expected, though not required, to >understand the WSDL extensibility points defined in this proposal. > >Understanding of these extensibility points promotes interoperability. When a >WSDL document contains these extensibility points, it is through these >extensibility points that a service advertises its supported and required >features. Therefore it is RECOMMENDED that implementations recognize, >understand and support these extensibility points. > >It is also possible for services to advertise features through other channels >(such as UDDI) in addition to these extensibility point. Mandating that every >conformant implementation recognize, understand and support these >extensibility points is considered to be too high a bar for conformant >implementations. Therefore, it is not required (though recommended) that every >conformant implementation support these extensibility point. > >II. Proposed Extensibility Elements > >II.A Compositor > >This proposal introduces a new extensibility element called a compositor. >The compositor semantics describe how features and properties are >composed for the enclosing component (or WSDL 1.1 element). The compositor's >semantics determine whether the composed elements are required or optional. >A compositor element can occur as a child element of wsdl11:portType, >wsdl11:operation (which may itself be a child of wsdl11:portType or >wsdl11:binding), and wsdl11:binding. The compositor element utilizes the >extensibility defined by WSDL 1.1. A compositor element specifies the >semantics for combining its children elements. These children elements can be >additional compositor, features, properties, or extensibility element(s). > >A compositor element is expressed by the following pseudo-syntax: > ><fnp:compositor uri="..."> > [fnp:feature/> | <fnp:property/> | <fnp:compositor/> | > <extensibility-element/>]+ ></fnp:compositor> > >The uri attribute of the compositor specifies its semantics. This >proposal describes four different compositors (URIs) and their semantics >below. It is possible to provide additional compositors by using >other URIs. The ability to define additional compositors and the existence of >extensibility points (represented by "<extensibility-element>") make the >framework extensible. > >1. all: this compositor specifies that all the children elements MUST > be used. This compositor is identified by using the URI: > "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/all"; > >2. choice: this compositor specifies that exactly one of the possibly > many children elements MUST be used. This compositor is identified by > using the URI: > "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/choice"; > >3. one-or-more: this compositor specifies that at least one of the > possibly many children elements MUST be used. This compositor is > identified by using the URI: > "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/one-or-more"; > >4. zero-or-more: this compositor specifies that one or more of the children > elements MAY be used (but it is not required). This > compositor is identified by using the URI: > "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/zero-or-more"; > >Examples for each compositor are provided in Section III below. > >II.B Feature > >A feature describes an abstract piece of functionality associated with a WSDL >element. This proposal places no restriction on what a feature may represent. >Typical expected examples of features include security, reliability and other >QoS aspects of Web services. A feature can occur only as a child of a >compositor. Whether a feature is required or not is defined by the enclosing >compositor(s). A feature is identified by a URI. Recognizing the URI of a >feature is considered to be equivalent to understanding the feature identified >by that URI. > >A feature element is expressed by the following pseudo-syntax: > ><fnp:feature uri="..."> > [<fnp:compositor/> | <extensibility-element/>]* ></fnp:feature> > >II.C Property > >A property is identified by a QName. A property can consists of either a value >or a constraint on the set of values. Typically properties are associated with >with a feature (but are not required to) and are descriped in a feature >specification. The QName identifier of a property uniquely identifies the >property. Recognizing the property QName identifier is considered to be >equivalent to understanding the semantics associated with that property. The >property QName identifier typically points a global XML Schema element >declaration. A property specification typically specifies the schema that >contains this global element declaration. A constraint on the set of values >that a property can have is specified by a QName that identifies a XML Schema >type. > ><fnp:property name="xs:QName"> > [<fnp:value>xs:anyType</fnp:value> | > <fnp:constraint>xs:QName</fnp:constraint>] > [<extensibility-element/>]* ></fnp:property> > >III. Compositor Examples: > >III.A Example for the "all" Compositor: > ><wsdl11:binding name="example-1"> > <fnp:compositor uri="..."> > <fnp:feature uri="http://example.com/security/non-repudiation";> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/all";> > <fnp:feature uri="http://example.com/security/dsig"/> > <fnp:feature uri="http://example.com/security/non-repudiation/country/us"/> > <fnp:feature uri="http://example.com/security/non-repudiation/receipt-ack"/> > </fnp:compositor> > </fnp:feature> > <fnp:feature uri="..."/> > <fnp:feature uri="..."/> > </fnp:compositor> > ... ><wsdl11:binding> > > >In the example above, the feature identified by URI >"http://example.com/security/non-repudiation"; is a feature that >specifies that the binding to which this feature is attached >supports non-repudiation. This feature consists of three other >features, all of which are required because of the semantics of the >'all' compositor that composes the three features. The feature >identified by the URI "http://example.com/security/dsig"; specifies >that every message sent and received by the binding must be >digitally signed. The feature identified by URI >"http://example.com/security/non-repudiation/country/us"; specifies >that the legal ramifications of non-repudiation are as defined by the >the United States laws. The feature identified by the URI >"http://example.com/security/non-repudiation/receipt-ack"; specifies >that the receipt of every non-ack message must be acknowledged by an >ack message. > >III.B Example for the "choice" compositor: > ><wsdl11:binding name="example2"> > <wsdl11:operation ...> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/choice";> > <fnp:feature uri="http://example.com/authentication/username-token"/> > <fnp:feature uri="http://example.com/authentication/X.509-token"/> > </fnp:compositor> > ... > </wsdl11:operation> > ... ></wsdl11:binding> > >In the example above, the binding "example-2" utilizes the "choice" >compositor that compose the two features. The feature identified by >the URI "http://example.com/authentication/username-token"; specifies >that a username should be used for authentication as per the OASIS WSS >Username Token profile. The feature identified by the URI >"http://example.com/authentication/X.509-token"; specifies that a X.509 >certificate should be used for authentication as per the OASIS WSS >X.509 Certificate token profile. Per definition of the compositor, the >binding allows a choice between one of these features for >authentication and requires that one method of authentication must be >used. > >Note that it is also possible to nest these two features under a >single feature as follows: > ><wsdl11:binding name="example3"> > <wsdl11:operation ...> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/all";> > <fnp:feature uri=""http://example.com/authentication";> > <fnp:compositor uri=""http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/choice";> > <fnp:feature uri="http://example.com/authentication/username-token"/> > <fnp:feature uri="http://example.com/authentication/X.509-token"/> > </fnp:compositor> > </fnp:feature> > </fnp:compositor> > ... > </wsdl11:operation> > ... ></wsdl11:binding> > >A feature identified by URI "http://example.com/authentication"; is a >feature that provides a choice between two features identified by the >URIs "http://example.com/authentication/username-token"; and >"http://example.com/authentication/X.509-token";. This feature is >required by the binding component per the semantics of "all" compositor. > >III.C Example for the "one-or-more" compositor: > ><wsdl11:binding name="example4" > xmlns:ex="http://example.com/reliability";> > <fnp:compositor uri="..."> > <fnp:feature uri="http://example.com/reliability";> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/one-or-more";> > <fnp:property name="ex:guaranteed-delivery"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:property name="ex:message-ordering"> > <fnp:value>total-ordering</fnp:value> > </fnp:property> > <fnp:property name="ex:duplicate-removal> > <fnp:value>true</fnp:value> > </fnp:property> > </fnp:compositor> > </fnp:feature> > </fnp:compositor> > .... ></wsdl11:binding> >In the example above, the feature identified by URI"http://example.com/reliability"; defines a reliable messaging protocol >and uses several properties that define quality of service that may be >provided by the feature. This example illustrates the usage of some of >these QoS for reliable messaging, such as delivery of messages in the >order received, removal of duplicate messages and guaranteeing that >messages are always delivered and how they may be utilized by using >the feature. > >In this example, the binding (where the feature is specified) uses at least >one of the three QoS provided by the feature by utilizing three different >properties. The semantics of the compositor illustrates that at least one of >the properties must be used that to indicate at least one of the QoS for >reliable messaging must be present. > >III.D Example for the "zero-or-more" compositor: > ><wsdl:portType name="example5" > xmlns:ex="http://example.com/ack/QoS";> > <wsdl11:operation ...> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/zero-or-more";> > <fnp:feature uri="http://example.com/ack";> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/zero-or-more";> > <fnp:property name="ex:within-24-hours"> > <fnp:value>true</fnp:value> > </fnp:property> > </fnp:compositor> > </fnp:feature> > <fnp:feature uri=..../> > </fnp:compositor> > ... > </wsdl11:operation> > ... ></wsdl11:portType> > >In the example above, the portType "example5" contains a list of >supported but not required features. Among these features, the feature >identified by URI "http://example.com/ack"; indicates that the client >will be acknowledged for the receipt of the message. This feature uses >one property, "http://example.com/ack/QoS/within-24-hours";. The >property "http://example.com/ack/QoS/within-24-hours"; indicates that an >acknowledgment would be sent within 24 hours when the property value >is true. If the property is used, it indicates that >acknowledgment within 24 hours will be provided by the feature per >the semantics of zero-or-more compositor. > >III.E Nested Compositor Example > ><wsdl11:portType name="example6"> > <wsdl11:operation ....> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/all";> > <fnp:feature uri="urn:f1"/> > <fnp:feature uri="urn:f2"/> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/zero-or-more";> > <fnp:feature uri="urn:f3"/> > <fnp:feature uri="urn:f3"/> > </fnp:compositor> > </fnp:feature> > </fnp:compositor> > </wsdl11:operation> > ... ></wsdl11:portType> > >This example illustrates that there are 4 different features that the >portType named "example6" supports. features f1 and f2 are required >features, on the other hand, features f3 and f4 are supported, but not >required. > >References: > >[1] http://lists.w3.org/Archives/Public/www-ws-desc/2004Jan/0153.html > > > >------------------------------------------------------------------------ > >WS-Reliability Specific Features and Properties Proposal >-------------------------------------------------------- > >I. Introduction > >This proposal defines WS-Reliability specific features and properties that can >be specified in a WSDL document using the features and properties extensible >framework. These features and properties when specified in a WSDL document >specify the reliability capabilities and assertions associated with specific >WSDL constructs. > >I.A Notational Convention > >This specification uses the following namespace prefixes: > > Prefix Namespace > ------ --------- > xs "http://www.w3.org/2001/XMLSchema"; > wsdl11 "http://schemas.xmlsoap.org/wsdl/"; > fnp "http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/"; > wsrm "http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > >The choice of any namespace prefix is arbitrary and not semantically >significant. > >II. WS-Reliability Feature > >The WS-Reliability feature is identified by the URI >"http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > >This feature URI identifies the WS-Reliability specification. Understanding >this URI implies understanding the WS-Reliability specification. > >III. WS-Reliability Properties > >This section identifies properties for the WS-Reliability specification. >Typically these properties would be scoped within the feature identified by the >URI "http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > >III.A. Guaranteed Delivery Property > >This property is identified by the QName "wsrm:guaranteed-delivery" and >corresponds to the semantics specified by the WS-Reliability guaranteed >delivery semantics. The type of this property is "xs:boolean". > >III.B. Duplicate Elimination Property > >This property is identified by the QName "wsrm:duplicate-elimination" and >corresponds to the semantics specified by the WS-Reliability duplicate >elimination semantics. The type of this property is "xs:boolean". > >III.C. Message Ordering Property > >This property is identified by the QName "wsrm:message-ordering" and >corresponds to the semantics specified by the WS-Reliability message >ordering semantics. The type of this property is "xs:boolean". > >III.D. Response Pattern Property > >This property is identified by the QName "wsrm:response-reply-pattern" and >corresponds to the semantics specified by the WS-Reliability response-reply >pattern semantics. The type of this property is "xs:boolean". > >III.E. Callback Pattern Property > >This property is identified by the QName "wsrm:callback-pattern" and >corresponds to the semantics specified by the WS-Reliability callback >pattern semantics. The type of this property is "xs:boolean". > >III.F. Poll Pattern Property > >This property is identified by the QName "wsrm:poll-pattern" and >corresponds to the semantics specified by the WS-Reliability poll >pattern semantics. The type of this property is "xs:boolean". > >IV. Client Side Properties > >In addition to the properties defined in section III, there are >WS-Reliability properties that are specified only at the client side (and >therefore do not occur in the WSDL document) deployment descriptors. >This section identifies such properties. These properties MUST NOT be specified >in the WSDL document. How the properties are specified and/or represented does >not affect interoperability as these properties are client-side only >properties. They are defined here for convenience only. > >IV.A. Group Expiry Time > >This property is identified by the QName "wsrm:group-expiry-time" and >corresponds to the semantics specified by the WS-Reliability group expiration >time. The type of this property is xs:dateTime. > >[[ Note: In most client-side deployments it is expected that >wsrm:group-expiry-time would be defined as something like "Now + duration", >rather than an absolute date/time (which would be translated into an absolute >date/time for every group). From that perspective it might be worthwhile >to define this property as xs:duration OR keep it untyped. ]] > >IV.B. Group Maximum Idle Duration > >This property is identified by the QName "wsrm:group-max-idle-duration" and >corresponds to the semantics specified by the WS-Reliability group maximum idle >duration. The type of this property is xs:duration. > >IV.C. Message Expiration Time > >This property is identified by the QName "wsrm:msg-expiry-time" and >corresponds to the semantics specified by the WS-Reliability message expiration >time. The type of this property is xs:dateTime. > >[[ Note: In most client-side deployments it is expected that >wsrm:msg-expiry-time would be defined as something like "Now + duration", >rather than an absolute date/time (which would be translated into an absolute >date/time for every message). From that perspective it might be worthwhile >to define this property as xs:duration OR keep it untyped. ]] > >IV.D. Retry Maximum Time > >This property is identified by the QName "wsrm:retry-max-times" and >corresponds to the semantics specified by the WS-Reliability maximum retry >times. The type of this property is xs:int. > >IV.E. Retry Time Interval > >This property is identified by the QName "wsrm:retry-time-interval" and >corresponds to the semantics specified by the WS-Reliability retry time >interval. The type of this property is xs:duration. > >IV.F. ReplyTo URI > >This property is identified by the QName "wsrm:reply-to" and >corresponds to the semantics specified by the WS-Reliability reply-to. >The type of this property is xs:anyURI. > >V. Schema > ><?xml version="1.0" encoding="UTF-8" ?> ><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"; > xmlns:wsrm="http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > targetNamespace="http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > elementFormDefault="qualified" > > > <!-- properties to be used in WSDL --> > <xs:element name="guaranteed-delivery" type="xs:boolean"/> > <xs:element name="duplicate-elimination" type="xs:boolean"/> > <xs:element name="message-ordering" type="xs:boolean"/> > <xs:element name="response-reply-pattern" type="xs:boolean"/> > <xs:element name="callback-reply-pattern" type="xs:boolean"/> > <xs:element name="poll-reply-pattern" type="xs:boolean"/> > > <!-- properties to be used on the client side --> > <xs:element name="group-expiry-time" type="xs:dateTime"/> > <xs:element name="group-max-idle-duration" type="xs:duration"/> > <xs:element name="msg-expiry-time" type="xs:dateTime"/> > <xs:element name="retry-max-times" type="xs:int"/> > <xs:element name="retry-time-interval" type="xs:duration"/> > <xs:element name="reply-to" type="xs:anyURI"/> > ></xs:schema> > >VI. Examples > >VI.A Example 1 > ><wsdl11:portType name="myReliablePort"> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositor/all";> > <fnp:feature uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/"; > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositor/all";> > <fnp:property name="wsrm:duplicate-elimination"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:property name="wsrm:message-ordering"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:property name="wsrm:guaranteed-delivery"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:compositor uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/fnp/compositors/one-or-more";> > <fnp:property name="wsrm:response-reply-pattern"> > <value>true</value> > </fnp:property> > <fnp:property name="wsrm:callback-reply-pattern"> > <value>true</value> > </fnp:property> > <fnp:property name="wsrm:poll-reply-pattern"> > <value>true</value> > </fnp:property> > </fnp:compositor> > </fnp:compositor> > </fnp:feature> > </fnp:compositor> > <wsdl11:operation> > ... > </wsdl11:operation> ></wsdl11:portType> > >VI.B Example 2: A simple client side DD > ><client-config> > <fnp:compositor uri="http://www.oasis-open.org/committees/schema/1.1/fnp/compositors/all";> > <fnp:feature uri="http://www.oasis-open.org/committees/wsrm/schema/1.1/feature/rel/";> > <fnp:compositor uri="http://www.oasis-open.org/committees/schema/1.1/fnp/compositors/all";> > <fnp:property name="wsrm:guaranteed-delivery"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:compositor uri="http://www.oasis-open.org/committees/schema/1.1/fnp/compositors/one-or-more";> > <fnp:property name="wsrm:response-reply-pattern"> > <fnp:value>true</fnp:value> > </fnp:property> > <fnp:compositor uri="http://www.oasis-open.org/committees/schema/1.1/fnp/compositors/all";> > <fnp:property name="wsrm:reply-to"> > <value>http://example.com/listener/</value> > </fnp:property> > <fnp:property name="wsrm:callback-reply-pattern"> > <fnp:value>true</fnp:value> > </fnp:property> > </fnp:compositor> > <fnp:property name="wsrm:poll-reply-pattern"> > <fnp:value>true</fnp:value> > </fnp:property> > </fnp:compositor> > <fnp:property name="wsrm:msg-expiry-time"> > <fnp:value>...</fnp:value> > </fnp:property> > <fnp:property name="wsrm:retry-time-interval"> > <fnp:value>...</fnp:value> > </fnp:property> > <fnp:property name="wsrm:retry-max-tries"> > <value>5</value> > </fnp:property> > </fnp:compositor> > </fnp:feature> > </fnp:compositor> ></client-config> > > > > >------------------------------------------------------------------------ > >To unsubscribe from this mailing list (and be removed from the roster of the OASIS TC), go to http://www.oasis-open.org/apps/org/workgroup/wsrm/members/leave_workgroup.php. > -- ---------------------------------------------------- Tom Rutt email: tom@coastin.com; trutt@fsw.fujitsu.com Tel: +1 732 801 5744 Fax: +1 732 774 5133
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