ProvenanceAccessScenarioUsingPAQ
From Provenance WG Wiki
Walk through of how the Provenance Access Scenario is satisfied using the Provenance Access and Query (W3C Editor's Draft 17 August 2011) proposal.
Contents |
Online HTML Documents D1 and D2
- Obtaining the document D
- HTML documents D1 and D2 are accessed using HTTP GET, and the web servers return Link: headers as follows. We show examples using both the alternate proposals for anchor as a parameter and as a relation.
- Using anchor parameter
GET https://github.com/timrdf/vsr/raw/master/data/source/tim-lebo/london-crime/version/2011-Jul-07/manual/crime.html HTTP/1.1 ... HTTP/1.1 200 OK ... Link: http://example.com/provenance/d1.prov; rel="provenance"; anchor="https://github.com/timrdf/vsr/raw/master/data/source/tim-lebo/london-crime/version/2011-Jul-07/manual/crime.html"
GET http://lists.w3.org/Archives/Public/public-prov-wg/2011Jul/att-0031/crime.html HTTP/1.1 ... HTTP/1.1 200 OK ... Link: http://example.com/provenance/d2.prov; rel="provenance"; anchor="http://lists.w3.org/Archives/Public/public-prov-wg/2011Jul/att-0031/crime.html"
- Using anchor relation
GET https://github.com/timrdf/vsr/raw/master/data/source/tim-lebo/london-crime/version/2011-Jul-07/manual/crime.html HTTP/1.1 ... HTTP/1.1 200 OK ... Link: http://example.com/provenance/d1.prov; rel="provenance"; Link: https://github.com/timrdf/vsr/raw/master/data/source/tim-lebo/london-crime/version/2011-Jul-07/manual/crime.html; rel="anchor"
GET http://lists.w3.org/Archives/Public/public-prov-wg/2011Jul/att-0031/crime.html HTTP/1.1 ... HTTP/1.1 200 OK ... Link: http://example.com/provenance/d2.prov; rel="provenance"; Link: http://lists.w3.org/Archives/Public/public-prov-wg/2011Jul/att-0031/crime.html; rel="anchor"
- Enacting the "Oh yeah?" feature
- A user requests a web browser (W) used to obtain the web documents (D1-2) to enact the "Oh yeah?" feature on the whole documents
- The web browser examines the HTTP response headers of the web documents to identify Link: headers and selects those that contain the relations, provenance or anchor.
- The browser extracts the provenance-uri information, I_P, from the provenance relation header. In the above example, I_P is http://example.com/provenance/d1.prov for D1 and http://example.com/provenance/d2.prov for D2.
- The browser also extracts the context-uri information, I_C, from the headers if the anchor parameter or relation were present. Otherwise, it uses the URL to the documents D1 and D2 that was used to access them as the value of I_C. In the above example, the anchor parameter or relation was present and the value of I_C is https://github.com/timrdf/vsr/raw/master/data/source/tim-lebo/london-crime/version/2011-Jul-07/manual/crime.html and http://lists.w3.org/Archives/Public/public-prov-wg/2011Jul/att-0031/crime.html for D1 and D2 respectively.
- Accessing the provenance
- 'What information (I) does the clients (W) need in order to access and retrieve the provenance for the documents D1-2?
