SPARQL PREFIX does not translated into @context

[bplatz]

The current test for PREFIX treats it as a source, but instead it is the equivalent to @context.

The current test that is passing, but incorrect is:

  (testing "external"
    (let [query "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\nSELECT ?name ?mbox\n WHERE {\n ?x foaf:name ?name.\n?x foaf:mbox ?mbox\n}"
          {:keys [prefixes where]} (sparql-to-ad-hoc query)]
      (is (= {:foaf "http://xmlns.com/foaf/0.1/"}
             prefixes))
      (is (= ["foaf" "foaf"]
             (mapv first where))))))

It should instead be this, and pass (note the where test is also incorrect, signifying special where logic when a PREFIX exists, but it should parse like a normal `where clause instead):

  (testing "prefix"
    (let [query "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\nSELECT ?name ?mbox\n WHERE {\n ?x foaf:name ?name.\n?x foaf:mbox ?mbox\n}"
          {:keys [context where]} (sparql-to-ad-hoc query)]
      (is (= {"foaf" "http://xmlns.com/foaf/0.1/"}
             context))
      (is (= [["$fdb" "?x" "foaf:name" ?name]
              ["$fdb" "?x" "foaf:mbox" "?mbox"]]
             where)))))

Also, there is no test that uses multiple PREFIX declarations. Hopefully that just works, or may warrant a separate ticket if not. Here is a test:

  (testing "multiple prefixes"
    (let [query "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n PREFIX ex: <http://example.org/ns/>\nSELECT ?name ?mbox\n WHERE {\n ?x foaf:name ?name.\n?x foaf:mbox ?mbox\n}"
          {:keys [context]} (sparql-to-ad-hoc query)]
      (is (= {"foaf" "http://xmlns.com/foaf/0.1/"
              "ex"   "http://example.org/ns/"}
             context)))))

[cap10morgan]

I worked on this as part of the recent v3 SPARQL work before I noticed this ticket existed. The new, passing SPARQL PREFIX test looks like this:

(testing "PREFIX declarations go into the context"
  (let [book-db @(fluree/stage db book-data)
        query   "PREFIX book: <http://example.org/book/>
                 SELECT ?book ?title
                 WHERE {?book book:title ?title.}"
        results @(fluree/query book-db query {:format :sparql})]
    (is (= [["book:1" "For Whom the Bell Tolls"]
            ["book:2" "The Hitchhiker's Guide to the Galaxy"]]
           results))))

[cap10morgan]

I'll add some other tests along the lines of what is suggested in here and make sure those pass as well.