1 files changed, 107 insertions, 0 deletions
diff --git a/creactistore/_templates/lib/rdflib/plugins/parsers/nquads.py b/creactistore/_templates/lib/rdflib/plugins/parsers/nquads.py
new file mode 100644
index 0000000..fbb4a37
--- /dev/null
+++ b/creactistore/_templates/lib/rdflib/plugins/parsers/nquads.py
@@ -0,0 +1,107 @@
+"""
+This is a rdflib plugin for parsing NQuad files into Conjunctive 
+graphs that can be used and queried. The store that backs the graph 
+*must* be able to handle contexts.
+
+>>> from rdflib import ConjunctiveGraph, URIRef, Namespace
+>>> g = ConjunctiveGraph()
+>>> data = open("test/example.nquads", "rb")
+>>> g.parse(data, format="nquads") # doctest:+ELLIPSIS
+<Graph identifier=... (<class 'rdflib.graph.Graph'>)>
+>>> assert len(g.store) == 449
+>>> # There should be 16 separate contexts
+>>> assert len([x for x in g.store.contexts()]) == 16
+>>> # is the name of entity E10009 "Arco Publications"? (in graph http://bibliographica.org/entity/E10009)
+>>> # Looking for:
+>>> # <http://bibliographica.org/entity/E10009> <http://xmlns.com/foaf/0.1/name> "Arco Publications" <http://bibliographica.org/entity/E10009>
+>>> s = URIRef("http://bibliographica.org/entity/E10009")
+>>> FOAF = Namespace("http://xmlns.com/foaf/0.1/")
+>>> assert(g.value(s, FOAF.name) == "Arco Publications")
+"""
+
+from rdflib.py3compat import b
+
+# Build up from the NTriples parser:
+from rdflib.plugins.parsers.ntriples import NTriplesParser
+from rdflib.plugins.parsers.ntriples import ParseError
+from rdflib.plugins.parsers.ntriples import r_tail
+from rdflib.plugins.parsers.ntriples import r_wspace
+from rdflib.plugins.parsers.ntriples import r_wspaces
+
+__all__ = ['QuadSink', 'NQuadsParser']
+
+class QuadSink(object):
+    def __init__(self):
+        class FakeStore(object):
+            def __init__(self, addn):
+                self.addN = addn
+        self.length = 0
+        self.__quads = []
+        self.__store = FakeStore(self.addN)
+        
+    def addN(self, quads):
+        self.length += 1
+        self.__quads.append(quads)
+        
+    def quads(self, (s,p,o)):
+        for s,p,o,ctx in self.__quads:
+            yield s,p,o,ctx
+
+class NQuadsParser(NTriplesParser):
+    def __init__(self, sink=None):
+        if sink is not None:
+            assert sink.store.context_aware, ("NQuadsParser must be given"
+                                          " a context aware store.")
+            self.sink = sink
+        else: self.sink = QuadSink()
+
+    def parse(self, inputsource, sink, **kwargs):
+        """Parse f as an N-Triples file."""
+        assert sink.store.context_aware, ("NQuadsParser must be given"
+                                          " a context aware store.")
+        self.sink = sink
+        
+        source = inputsource.getByteStream()
+        
+        if not hasattr(source, 'read'):
+            raise ParseError("Item to parse must be a file-like object.")
+
+        self.file = source
+        self.buffer = ''
+        while True:
+            self.line = self.readline()
+            if self.line is None: break
+            try: self.parseline()
+            except ParseError:
+               raise ParseError("Invalid line: %r" % self.line)
+        return self.sink
+  
+    def context(self):
+        context = self.uriref()
+        if not context:
+            raise ParseError("Context must be a uriref")
+        return context
+  
+    def parseline(self):
+        self.eat(r_wspace)
+        if (not self.line) or self.line.startswith(b('#')):
+            return # The line is empty or a comment
+
+        subject = self.subject()
+        self.eat(r_wspaces)
+
+        predicate = self.predicate()
+        self.eat(r_wspaces)
+
+        obj = self.object()
+        self.eat(r_wspaces)
+      
+        context = self.context()
+        self.eat(r_tail)
+
+        if self.line:
+            raise ParseError("Trailing garbage")
+        # Must have a context aware store - add on a normal Graph
+        # discards anything where the ctx != graph.identifier
+        self.sink.store.add((subject, predicate, obj), context)
+