RDF graph core.logic

rdf-cl.clj

;; http://www.infoq.com/presentations/core-logic

(ns rdf
  (:refer-clojure :exclude [==])
  (:use [clojure.core.logic]))

(def g
  [[:a1 :rdf/type :sdx/FederationService]
   [:a1 :rdf/type :sdx/name "movies"]
   [:a1 :rdf/exposedServices :_syscoll1]
   [:_syscoll1 :sdx/service :a2]

   [:a2 :rdf/type :sdx/FederationService]
   [:a2 :rdf/name "imdb"]
   [:a2 :sdx/identifier "<http://base/movies"]
   [:a2 :sdx/queryTimeout 5]
   [:a2 :rdf/exposedServices :_syscoll2]
   [:_syscoll2 :rdf/type :sdx/ServiceCollection]
   [:_syscoll2 :sdx/service :a3]
   [:_syscoll2 :sdx/service :a4]

   [:a3 :rdf/type :sd/Service]
   [:a3 :sd/endpoint "http://localhost:9090/spyder/instance2"]

   [:a4 :rdf/type :sd/Service]
   [:a4 :sd/endpoint "http://localhost:9090/spyder/instance1"]
   [:a4 :sd/supportedLanguage :sd/SPARQL11Query]
   [:a4 :sd/resultFormat "<http://www.w3.org/ns/formats/Turtle>"]
   [:a4 :sd/defualtDatasetDescription :a5]
   ])

(defn endpointo [g q]
     (fresh [a b c d e f]
            (membero [a :rdf/type :sdx/FederationService] g)
            (membero [a :rdf/exposedServices b] g)
            (membero [b :sdx/service c] g)
            (membero [c :rdf/type :sdx/FederationService] g)
            (membero [c :rdf/exposedServices d] g)
            (membero [d :sdx/service e] g)
            (membero [e :rdf/type :sd/Service] g)
            (membero [e :sd/endpoint q] g)))

(run* [q]
      (endpointo g q))

(run 1 [g]
     (endpointo g "http://localhost:1234/ole"))