--- a/paq/provenance-access.html Thu Aug 11 12:26:25 2011 +0100
+++ b/paq/provenance-access.html Wed Aug 17 12:55:55 2011 +0100
@@ -133,26 +133,39 @@
<dt>Provenance information</dt>
<dd>refers to provenance represented in some fashion.</dd>
<dt>Provenenance-URI</dt>
- <dd>A URI denoting some provenance information.</dd>
- <dt>Target</dt>
- <dd>an entity about which one wants to know the provenance.</dd>
- <dt>Target-URI</dt>
- <dd>a URI denoting a target, which allows the target to be found in some provenance information.</dd>
+ <dd>a URI denoting some provenance information.</dd>
+ <dt>Context</dt>
+ <dd>an entity, or aspect of a resource, about which one wants to present the provenance.</dd>
+ <dt>Context-URI</dt>
+ <dd>a URI denoting a context, which allows that context to be isolated in some provenance information (see <a href="#provenance-context"></a> for discussion)</dd>
<dt>Provenance service</dt>
- <dd>a service that provides a Provenance-URI or provenance information given a Target-URI.</dd>
+ <dd>a service that provides a Provenance-URI or provenance information given a resource URI or context-URI.</dd>
<dt>Service-URI</dt>
<dd>the URI of a Provenance Service.</dd>
<dt>Resource</dt>
- <dd>a web resource. A resource may be associated with multiple targets.</dd>
+ <dd>a web resource, as <a href="http://www.w3.org/TR/webarch/#id-resources">described</a> by the Architecture of the World Wide Web [[WEBARCH]], section 2.2. A resource may be associated with multiple contexts (see <a href="#provenance-context"></a> for discussion)</dd>
</dl>
</p>
- <p>
- A key notion within these concepts is that a resource may not be the same as a target. Within provenance information, the provenance for a resource may be described with respect to a restricted view of that resource (e.g. the resource at a particular time). This restricted view is termed a target and a Target-URI allows one to locate that target within provenance information. Therefore, the Target-URI connects this restricted view of a resource with the resource itself.
- </p>
-
<p class="issue">
- Are we treading to much on the model territory here? How can we explain this only a target identifies an Entity in the provenance model?
+ The terms context and context-URI are chosen to align with terminology used in describing the HTTP link header (a href="http://tools.ietf.org/html/rfc5988#section-5.2£>http://tools.ietf.org/html/rfc5988#section-5.2</a>) - does this terminology work in the current (ahem) context? See also next section.
+ </p>
+
+ </section>
+
+ <section>
+ <h2 id="provenance-context">Provenance, context and resources</h2>
+ <p class="pending">
+ This section has been drafted to address a number of concerns: (a) to avoid previous use of "Target" for the topic of a provenance assertion (cf. http://www.w3.org/2011/prov/track/issues/74), and (b) to clarify the use of different resources as views on a dynamic or variable subject of provenance.
+ </p>
+ <p>
+ Fundamentally, provenance information is <em>about</em> web resources, in the <a href="http://www.w3.org/TR/webarch/#id-resources">sense described</a> by the Architecture of the World Wide Web [[WEBARCH]]. In general, web resources may vary over time and context: e.g., a resource describing the weather in London changes from day-to-day, or one listing restaurants near you will vary depending on your location. Provenance information, to be useful, must be persistent and not itself dependent on context. Yet we may still want to make provenance assertions about dynamic or context-varying web resources (e.g. the weather forecast for London on a particular day may have been derived from a particular set of Meteorological Office data).
+ </p>
+ <p>
+ Provenance descriptions of dynamic and context-dependent resources are possible through the notion of "contexts". A context is simply a web resource that is a contextualized view or instance of an original web resource. For example, a W3C specification typically undergoes several public revisions before it is finalized. A URI that refers to the "current" revision might be thought of as denoting the specification through its lifetime. Separate URIs for each individual revision would then be context-URIs, denoting the specification at a particular stage in its development. Using these, we can make provenance assertions that a particular revision was published on a particular date, and was last modified by a particular editor.
+ </p>
+ <p>
+ In summary, a key notion within the concepts outlined above is that provenance information may be not universally applicable to a resource, but may be described with respect to a restricted view of that resource (e.g. the resource at a particular time). This restricted view is termed a context, and a context-URI allows one to refer to that context within the provenance information. The context-URI used to describe this restricted view of a resource is also related to the resource itself, and requests for provenance about a resource may return provenance information that uses one or more context-URIs to refer to the resource.
</p>
</section>
@@ -181,16 +194,16 @@
On the presumption that provenance information is a resource that can be accessed using normal web retrieval, one needs to know a Provenance-URI to dereference. The Provenance-URI may be known in advance, in which case there is nothing more to specify. If a Provenance-URI is not known, then a mechanism to discover one must be based on some information that is available to the would-be accessor. We also wish to allow that provenance information could be provided by parties other than the provider of the original resource. Indeed, provenance information for a resource may be provided by several different parties, at different URIs, each with different concerns. It is quite possible that different parties may provide contradictory provenance information.
</p>
<p>
- Once provenance information information is retrieved, one needs how to identify the view of that resource within that provenance information. This view is known as the target and is identified by a Target-URI.
+ Once provenance information information is retrieved, one needs how to identify the view of that resource within that provenance information. This view is known as the context and is identified by a context-URI.
</p>
<p>
- We start by considering mechanisms for the resource provider to indicate a Provenance-URI along with a Target-URI. Because the resource provider controls the response when the resource is accessed, direct indication of these URIs is possible. Three mechanisms are described here:
+ We start by considering mechanisms for the resource provider to indicate a provenance-URI along with a context-URI. Because the resource provider controls the response when the resource is accessed, direct indication of these URIs is possible. Three mechanisms are described here:
<ul>
<li>The requester knows the Resource <em>and</em> the resource is accessed using HTTP</li>
<li>The requester has a copy of a resource presented as HTML or XHTML</li>
<li>The requester has a copy of a resource presented as RDF (including the range of possible RDF syntaxes, such as HTML with embedded RDFa)</li>
</ul>
- These particular cases are selected as corresponding to primary current web protocol and data formats. Finally, in <a href="#arbitrary-target" class="sectionRef"></a>, we discuss the case of a resource in an unspecified format which has been provided by some means other than HTTP.
+ These particular cases are selected as corresponding to primary current web protocol and data formats. Finally, in <a href="#arbitrary-data" class="sectionRef"></a>, we discuss the case of a resource in an unspecified format which has been provided by some means other than HTTP.
</p>
<section>
@@ -198,25 +211,34 @@
<p>
For a document accessible using HTTP, POWDER [[POWDER-DR]] describes <a href="http://www.w3.org/TR/2009/REC-powder-dr-20090901/#httplink">a mechanism</a> for associating metadata with a resource using an HTTP <code>Link</code> header field. The <code>Link</code> header field is included in the HTTP response to a GET or HEAD operation (other HTTP operations are not excluded, but are not considered here). Since the POWDER specification was published, the HTTP linking draft has been approved by the IETF as <a href="http://tools.ietf.org/html/rfc5988">RFC 5988</a> [[LINK-REL]].
</p>
+ <p class="issue">
+ Pick one or allow either of the following?:
+ </p>
<p>
The same basic mechanism can be used for referencing provenance information, for which two new link relation types are registered according to the template in <a href="#iana-considerations" class="sectionRef"></a>:
- <p class="pattern">
- <code>Link: <cite>provenance-URI</cite>; rel="provenance"</code>
- <code>Link: <cite>target-URI</cite>; rel="target"</code>
- </p>
- When used in conjunction with an HTTP success response code (<code>2xx</code>), this HTTP header indicates that <code><cite>provenance-URI</cite></code> is the URI of some provenance for the requested resource and that resource's associated target is identified by the <code><cite>target-URI</cite></code>.
+ <code>
+ <pre class="pattern">
+ Link: <cite>provenance-URI</cite>; rel="provenance"
+ Link: <cite>context-URI</cite>; rel="anchor"</pre>
+ </code>
+ or
+ <code>
+ <pre class="pattern">
+ Link: <cite>provenance-URI</cite>; rel="provenance"; anchor="<cite>context-URI</cite>"</pre>
+ </code>
+ When used in conjunction with an HTTP success response code (<code>2xx</code>), this HTTP header indicates that <code><cite>provenance-URI</cite></code> is the URI of some provenance for the requested resource and that the associated resource context is identified by <code><cite>context-URI</cite></code>.
</p>
<p>
- If no target link is provided then the <code><cite>target-URI</cite></code> is assumed to be the URI of the resources. It is RECOMMENDED that this only be done when the resource is static.
+ If no <code>anchor</code> link is provided then the <code><cite>context-URI</cite></code> is assumed to be the URI of the resource.
</p>
<p>
At this time, the meaning of these links returned with other HTTP response codes is not defined: future revisions of this specification may define interpretations for these.
</p>
<p>
- An HTTP response MAY include multiple provenance link headers, indicating a number of different resources that are known to the responding server, each providing provenance about the accessed resource. Likewise, an HTTP response MAY inclue multiple target link headers, that indicate the resource may be identified within provenance information using all of these <code><cite>target-URIs</cite></code>.
+ An HTTP response MAY include multiple <code>provenance</code> link headers, indicating a number of different resources that are known to the responding server, each providing provenance about the accessed resource. Likewise, an HTTP response MAY include multiple <code>anchor</code> link headers, that indicate the resource may have provenance information associated with all of the indicated <code><cite>context-URIs</cite></code>.
</p>
<p>
- The presence of a provenance link in an HTTP response does not preclude the possibility that other publishers may offer provenance information about the same resource. In such cases, discovery of the additional provenance information must use other means (e.g. see <a href="#third-party-services" class="sectionRef"></a>).
+ The presence of a provenance link in an HTTP response does not preclude the possibility that other publishers may offer provenance information about the same resource. In such cases, discovery of the additional provenance information must use other means (e.g. see <a href="#provenance-discovery-services" class="sectionRef"></a>).
</p>
<p class="issue">
@@ -228,7 +250,7 @@
<section>
<h2>Resource presented as HTML</h2>
<p class="pending">
- Addresses <a href="http://www.w3.org/2011/prov/track/issues/46">ISSUE 46</a> with target link-relation.
+ Addresses <a href="http://www.w3.org/2011/prov/track/issues/46">ISSUE 46</a> by adding "anchor" link-relation.
</p>
<p>
For a document presented as HTML or XHTML, without regard for how it has been obtained, POWDER [[POWDER-DR]] describes <a href="http://www.w3.org/TR/2009/REC-powder-dr-20090901/#assoc-markup">a mechanism</a> for associating metadata with a resource by adding a <code><Link></code> element to the HTML <code><head></code> section.
@@ -241,7 +263,7 @@
<head>
<meta name="wdr.issuedby" content="http://authority.example.org/company.rdf#me"/>
<link rel="provenance" href="<cite>provenance-URI</cite>">
- <link rel="target" href="<cite>target-URI</cite>">
+ <link rel="anchor" href="<cite>context-URI</cite>">
<title>Welcome to example.com</title>
</head>
<body>
@@ -250,16 +272,21 @@
</html>
</pre>
</code>
- The <code><cite>provenance-URI</cite></code> given by the <code>provenance</code> link element identifies the Provenance-URI for the document where the <code><cite>target-URI</cite></code> given by the <code>target</code> link element specifies the identifier of the presented document view, and which is used within the provenance information when referring to this document.
</p>
<p>
- An HTML document header MAY include multiple provenance link elements, indicating a number of different resources that are known to the creator of the document, each providing provenance about the document.
+ The <code><cite>provenance-URI</cite></code> given by the <code>provenance</code> link element identifies the provenance-URI for the document.
</p>
<p>
- Likewise, the header MAY include multiple target link elements indicating that the document can be identified in the provenance information with multiple <code><cite>target-URIs</cite></code>.
+ The <code><cite>context-URI</cite></code> given by the <code>anchor</code> link element specifies an identifier for the presented document view, and which may be used within the provenance information when referring to this document.
</p>
<p>
- If no target link element is provided then the <code><cite>target-URI</cite></code> is assumed to be the URI of the document. It is RECOMMENDED that this only be done when the document is static.
+ An HTML document header MAY include multiple "provenance" link elements, indicating a number of different resources that are known to the creator of the document, each providing provenance about the document.
+ </p>
+ <p>
+ Likewise, the header MAY include multiple "anchor" link elements indicating that, e.g., different revisions of the document can be identified in the provenance information using the different <code><cite>context-URIs</cite></code>.
+ </p>
+ <p>
+ If no "anchor" link element is provided then the <code><cite>context-URI</cite></code> is assumed to be the URI of the document. It is RECOMMENDED that this only be done when the document is static.
</p>
<section>
@@ -276,7 +303,7 @@
<head>
<meta name="wdr.issuedby" content="http://authority.example.org/company.rdf#me"/>
<link rel="provenance-service" href="<cite>provenance-service-URI</cite>">
- <link rel="target" href="<cite>target-URI</cite>">
+ <link rel="anchor" href="<cite>context-URI</cite>">
<title>Welcome to example.com</title>
</head>
<body>
@@ -286,8 +313,8 @@
</pre>
</code>
<p>
- The <code>provenance-service</code> link element identifies the service URI. Dereferencing this URI yields a service description that provides further information to enable a client to determine a Provenance-URI for a target; see <a href="#provenance-discovery-service" class="sectionRef"></a> for more details.
- There may be multiple <code>provenance-service</code> link elements, and these MAY appear in the same document as <code>target</code> and <code>provenance</code> link elements (though, in practice, there may be little point in providing both <code>provenance</code> and <code>provenance-service</code> links).
+ The <code>provenance-service</code> link element identifies the service URI. Dereferencing this URI yields a service description that provides further information to enable a client to determine a provenance-URI for a context; see <a href="#provenance-discovery-service" class="sectionRef"></a> for more details.
+ There may be multiple <code>provenance-service</code> link elements, and these MAY appear in the same document as <code>anchor</code> and <code>provenance</code> link elements (though, in practice, there may be little point in providing both <code>provenance</code> and <code>provenance-service</code> links).
</p>
</section>
<p class="issue">
@@ -316,7 +343,7 @@
For this purpose a new RDF property, <code>prov:hasProvenance</code>, is defined as a relation between two resources, where the object of the property is a resource that provides provenance information about the subject resource. Multiple <code>prov:hasProvenance</code> assertions may be made about a subject resource.
</p>
<p>
- Another new RDF property, <code>prov:hasTarget</code>, is defined to allow the RDF content to specify one or more target-URIs of the RDF document for the purpose of provenance information (similar to the use of the target link relation in HTML).
+ Another new RDF property, <code>prov:hasContext</code>, is defined to allow the RDF content to specify one or more context-URIs of the RDF document for the purpose of provenance information (similar to the use of the "anchor" link relation in HTML).
</p>
<p class="issue">
@@TODO: needs to be completed.
@@ -338,7 +365,7 @@
If a resource is presented using a data format other than HTML or RDF, and no URI for the resource is known, provenance discovery becomes trickier to achieve. This specification does not define a specific mechanism for such arbitrary resources, but this section discusses some of the options that might be considered.
</p>
<p>
- For formats which have provision for including metadata within the file (e.g. JPEG images, PDF documents, etc.), use the format-specific metadata to include a Target-URI and/or Provenance-URI.
+ For formats which have provision for including metadata within the file (e.g. JPEG images, PDF documents, etc.), use the format-specific metadata to include a context-URI and/or provenance-URI.
</p>
<p>
Use a generic packaging format that can combine an arbitrary data file with a separate metadata file in a known format, such as RDF. At this time, it is not clear what format that should be, but some possible candidates are:
@@ -393,11 +420,11 @@
<section>
<h2>Retrieve Provenance-URIs for a resource</h2>
<p>
- To use the provenance discovery service to retrieve a list of provenance-URIs for a resource, starting with the discovery service URI (<code>service-URI</code>) and the URI of the target resource (<code>target-URI</code>):
+ To use the provenance discovery service to retrieve a list of provenance-URIs for a resource, starting with the discovery service URI (<code>service-URI</code>) and the URI of the context resource (<code>context-URI</code>):
<ol>
<li>Dereference <code>service-URI</code> to obtain a representation of the <cite>service description</cite> in one of the formats described below.</li>
<li>Extract the <cite>provenance location template</cite> from the service description.</li>
- <li>Use the provenance location template with <code>target-URI</code> for template variable <code>uri</code> to form <code>provenance-location-URI</code>.</li>
+ <li>Use the provenance location template with <code>context-URI</code> for template variable <code>uri</code> to form <code>provenance-location-URI</code>.</li>
<li>Dereference <code>provenance-location-URI</code> to obtain a <cite>provenance locations</cite> resource in one of the formats described below.</li>
</ol>
</p>
@@ -409,11 +436,11 @@
<section>
<h2>Retrieve Provenance information for a resource</h2>
<p>
- To use the provenance discovery service to retrieve provenance information for a resource, starting with the discovery service URI (<code>service-URI</code>) and the URI of the resource (<code>target-URI</code>):
+ To use the provenance discovery service to retrieve provenance information for a resource, starting with the discovery service URI (<code>service-URI</code>) and the URI of the resource (<code>context-URI</code>):
<ol>
<li>Dereference <code>service-URI</code> to obtain a representation of the <cite>service description</cite> in one of the formats described below.</li>
<li>Extract the <cite>provenance information template</cite> from the service description.</li>
- <li>Use the provenance information template with <code>target-URI</code> for template variable <code>uri</code> to form <code>provenance-URI</code>.</li>
+ <li>Use the provenance information template with <code>context-URI</code> for template variable <code>uri</code> to form <code>provenance-URI</code>.</li>
<li>Dereference <code>provenance-URI</code> to obtain <cite>provenance information</cite> as described by the provenance model document [[PROV-MODEL]] @@TODO: fix up name, reference.</li>
</ol>
</p>
@@ -490,14 +517,13 @@
<section>
<h2>Provenance locations</h2>
<p>
- A resource that enumerates one or more Provenance-URIs associated with a target resource.
+ A provenance locations resource enumerates one or more provenance-URIs associated with a given resource.
</p>
<p>
- The examples below are for a target resource URI <code>http://example.info/qdata/</code>, and
- using the service description example above, its URI would be <code>http://example.info/provenance_service/location/?uri=http%3A%2F%2Fexample.info%2Fqdata%2F</code>.
+ The examples below are for a given resource URI <code>http://example.info/qdata/</code>, and using the service description example above, its URI would be <code>http://example.info/provenance_service/location/?uri=http%3A%2F%2Fexample.info%2Fqdata%2F</code>.
</p>
<p class="note">
- The template might use <code>?uri={+uri}</code> rather than just <code>?uri={uri}</code>, and thereby avoid %-escaping the <code>:</code> and <code>/</code> characters in the target resource URI, but this could cause difficulties for target URIs containing query parameters and/or fragment identifiers. In this case, the client application would need to ensure that any such characters were %-escaped <em>before</em> being passed into a URI-template expansion processor.
+ The template might use <code>?uri={+uri}</code> rather than just <code>?uri={uri}</code>, and thereby avoid %-escaping the <code>:</code> and <code>/</code> characters in the given URI, but this could cause difficulties for URIs containing query parameters and/or fragment identifiers. In this case, the client application would need to ensure that any such characters were %-escaped <em>before</em> being passed into a URI-template expansion processor.
</p>
<section>
<h2>JSON example of provenance locations</h2>
@@ -507,7 +533,7 @@
<code>
<pre class="example">
{
- "target_uri": "http://example.info/qdata/",
+ "uri": "http://example.info/qdata/",
"provenance": [
"http://source1.example.info/provenance/qdata/",
"http://source2.example.info/prov/qdata/",
@@ -567,7 +593,7 @@
Provenance information about a resource or resources may be returned in any format. It is recommended that the format be one defined by the Provenance Model specification [[PROV-MODEL]].
</p>
<p>
- Assuming a target resource URI <code>http://example.info/qdata/</code>, and
+ Assuming a given resource URI <code>http://example.info/qdata/</code>, and
using the service description example above, the provenance URI would be <code>http://example.info/provenance_service/provenance/?uri=http%3A%2F%2Fexample.info%2Fqdata%2F</code>.
</p>
</section>
@@ -600,13 +626,13 @@
We assume that the requesting application has the URI of a provenance query service, and some information about the resource for which provenance information is required that can be used as the basis for a query. A query service is potentially a very general capability that can, in principle, subsume the provenance discovery service described in <a href="#provenance-discovery-service" class="sectionRef"></a>, but which may be more complex to deploy and use for simple provenance discovery cases..
</p>
<p>
- The details of a provenance query service is an implementation choice, to be agreed between provider and users of the service, but for ease of interoperability between different providers and users we recommend use of SPARQL [[RDF-SPARQL-PROTOCOL]] [[RDF-SPARQL-QUERY]]. The query service URI would then be the URI of a SPARQL endpoint (or, to use the SPARQL specification language, a <a href="http://www.w3.org/TR/rdf-sparql-protocol/#conformant-sparql-protocol-service">SPARQL protocol service</a>). A query service can potentially be used in many different ways, limited only by the available information and capabilities of theSPARQL query language; the following subsections provide examples for what are considered to be some plausible common scenarios.
+ The details of a provenance query service is an implementation choice, to be agreed between provider and users of the service, but for ease of interoperability between different providers and users we recommend use of SPARQL [[RDF-SPARQL-PROTOCOL]] [[RDF-SPARQL-QUERY]]. The query service URI would then be the URI of a SPARQL endpoint (or, to use the SPARQL specification language, a <a href="http://www.w3.org/TR/rdf-sparql-protocol/#conformant-sparql-protocol-service">SPARQL protocol service</a>). A query service can potentially be used in many different ways, limited only by the available information and capabilities of the SPARQL query language; the following subsections provide examples for what are considered to be some plausible common scenarios.
</p>
<section>
- <h2>Find Provenance-URI given Target-URI of resource</h2>
+ <h2>Find provenance-URI given context-URI of resource</h2>
<p>
- If the requester has a Target-URI for the original resource, they might simply issue a simple SPARQL query for the URI(s) of any associated provenance information; e.g., if the original resource has URI <code>http://example.org/resource</code>,
+ If the requester has a context-URI for the original resource, they might simply issue a simple SPARQL query for the URI(s) of any associated provenance information; e.g., if the original resource has a context-URI <code>http://example.org/resource</code>,
<code>
<pre class="example">
@prefix prov: <@@TBD>
@@ -625,7 +651,7 @@
<section>
<h2>Find Provenance-URI given identifying information about a resource</h2>
<p>
- If the requester has identifying information that is not the URI of the original resource, then they will need to construct a more elaborate query to locate the target resource and obtain its Provenance-URI(s). The nature of identifying information that can be used in this way will depend upon the third party service used, further definition of which is out of scope for this specification. For example, a query for a document identified by a DOI, say <code>1234.5678</code>, using the PRISM vocabulary [[PRISM]] recommended by FaBio [[FABIO]], might look like this:
+ If the requester has identifying information that is not the URI of the original resource, then they will need to construct a more elaborate query to locate a context resource and obtain its provenance-URI(s). The nature of identifying information that can be used in this way will depend upon the third party service used, further definition of which is out of scope for this specification. For example, a query for a document identified by a DOI, say <code>1234.5678</code>, using the PRISM vocabulary [[PRISM]] recommended by FaBio [[FABIO]], might look like this:
<code>
<pre class="example">
@prefix prov: <@@TBD>
@@ -643,12 +669,12 @@
</section>
<section>
- <h2>Obtain provenance information directly given Target-URI of a resource</h2>
+ <h2>Obtain provenance information directly given context-URI of a resource</h2>
<p>
This scenario retrieves provenance information directly given the URI of a resource, and may be useful where the provenance information has not been assigned a specific URI, or when the calling application is interested only in specific elements of provenance information.
</p>
<p>
- If the original resource has URI <code>http://example.org/resource</code>, a SPARQL query for provenance information might look like this:
+ If the original resource has a context-URI <code>http://example.org/resource</code>, a SPARQL query for provenance information might look like this:
<code>
<pre class="example">
@prefix prov: <@@TBD>
@@ -662,10 +688,10 @@
}
</pre>
</code>
- This query essentially extracts all available properties and values available from the query service used that are directly about the specified resource, and returns them as an RDFG graph. This may be fine if the service contains <em>only</em> provenance information about the indicated resource, or if the non-provenance information is also of interest. A more complex query using specific provenance vocabulary terms may be needed to selectively retrieve just provenance information when other kinds of information are also available.
+ This query essentially extracts all available properties and values available from the query service used that are directly about the specified context resource, and returns them as an RDF graph. This may be fine if the service contains <em>only</em> provenance information about the indicated resource, or if the non-provenance information is also of interest. A more complex query using specific provenance vocabulary terms may be needed to selectively retrieve just provenance information when other kinds of information are also available.
</p>
<p class="issue">
- @@TODO: specific provenance namespace and property to be determined by the model specification? The above query pattern assumes provenance information is included in direct properties about the target resource. When an RDF provenance vocabulary is formulated, this may well turn out to not be the case. A better example would probably be one that retrieves specific provenance information when the vocabulary terms have been defined.
+ @@TODO: specific provenance namespace and property to be determined by the model specification? The above query pattern assumes provenance information is included in direct properties about the context resource. When an RDF provenance vocabulary is formulated, this may well turn out to not be the case. A better example would probably be one that retrieves specific provenance information when the vocabulary terms have been defined.
</p>
</section>
@@ -700,7 +726,7 @@
</dd>
<dt>Description:</dt>
<dd>
- the resource identified by target URI of the link provides provenance information about the resource identified by the context link
+ the resource identified by target IRI of the link provides provenance information about the resource identified by the context link
</dd>
<dt>Reference:</dt>
<dd>
@@ -718,19 +744,19 @@
</p>
</section>
<section>
- <h2>Registration template for link relation: "target"</h2>
- <p class="target">
- The name "target" is unfortunate, as it has specific meaning in the context of a link relation (I think). Reconsider?
+ <h2>Registration template for link relation: "anchor"</h2>
+ <p class="pending">
+ The name "anchor" has been used for the link relation name, despite the corresponding URI being described as a context-URI. This terminology has been chosen to align with usage in the description of the HTTP Link header field, per <a href="http://tools.ietf.org/html/rfc5988#section-5.2">RFC 5988</a>.
</p>
<p>
<dl>
<dt>Relation Name:</dt>
<dd>
- <code>target</code>
+ <code>anchor</code>
</dd>
<dt>Description:</dt>
<dd>
- the resource identified by target URI of the link is one for which provenance information is provided. This may be used, for example, to extract relevant information from a referenced document that contains provenance information for several targets.
+ the resource identified by target URI of the link is a context-URI for which provenance information may be provided. This may be used, for example, to isolate relevant information from a referenced document that contains provenance information for several contexts.
</dd>
<dt>Reference:</dt>
<dd>
@@ -820,7 +846,7 @@
There are clearly a number of capabilities needed for a provenance-aware application that are not covered by the mechanisms described above. But most of these amount to implementation details and decisions for a particular application, and as such are beyond the scope of this document to specify.
</p>
<p>
- One feature not covered above that might be a candidate for specification is a common format for a data package that combines original content along with provenance-related metadata or data. At this stage, it is not clear what format that might take, but some possible candidates are discussed in <a href="#arbitrary-target" class="sectionRef"></a>.
+ One feature not covered above that might be a candidate for specification is a common format for a data package that combines original content along with provenance-related metadata or data. At this stage, it is not clear what format that might take, but some possible candidates are discussed in <a href="#arbitrary-data" class="sectionRef"></a>.
In any case, it seems to me that a specification that is specific for provenance to the exclusion of other metadata is unlikely to obtain traction, as provenance is just part of a wider landscape of information quality, trust, preservation and more.
</p>
</section>