Graph drafter/graph-modified-times is not modified whilst in draft

[scottlowe]

When the contents of a draft dataset are updated, the public http://publishmydata.com/graphs/drafter/graph-modified-times graph is not modified whilst in the draft. In client applications, e.g. muttnik, one needs to check both live and in the draft graph for modified times e.g. http://publishmydata.com/graphs/drafter/draft/7407ab26-9d9f-411d-8fd0-a93e98e7ffd2.

This is because the entire modified graph doesn’t get cloned into the draftset, only the modified graphs. This behaviour is different to the usual Drafter workflow where Drafter transparently takes care of it, such that queries work the same whether inside a draft or not, when rewritten.

The upshot is that just querying the graph in the draft endpoint won't work.

For example, the following query for modified times on a Dataset does not work in muttnik when in draft:

PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX pmdcat: <http://publishmydata.com/pmdcat#>
PREFIX pmdui: <http://publishmydata.com/def/pmdui/>

CONSTRUCT {
    <http://muttnik.gov/data/crimes-ds> pmdui:drafter-modified-date ?modified .
}
WHERE {

    GRAPH <http://muttnik.gov/graph/metadata/crimes> {
        ?cat_entry pmdcat:graph ?cat_graph .
    }

    GRAPH <http://publishmydata.com/graphs/drafter/graph-modified-times> {
        ?cat_graph dcterms:modified ?modified .
    }
}

the above is rewritten to:

PREFIX  pmdcat: <http://publishmydata.com/pmdcat#>
PREFIX  rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX  pmdui: <http://publishmydata.com/def/pmdui/>

CONSTRUCT
  {
    <http://muttnik.gov/data/crimes-ds> pmdui:drafter-modified-date ?modified .
  }
WHERE
  { GRAPH <http://muttnik.gov/graph/metadata/crimes>
      { ?cat_entry  pmdcat:graph  ?cat_graph }
     
    GRAPH <http://publishmydata.com/graphs/drafter/draft/7407ab26-9d9f-411d-8fd0-a93e98e7ffd2>
      { ?cat_graph  dcterms:modified  ?modified }
  }