Adapter to use PyLD's json-ld parser to add triples to librdf.

diff --git a/htsworkflow/util/rdfjsonld.py b/htsworkflow/util/rdfjsonld.py
new file mode 100644 (file)
index 0000000..45046a5
--- /dev/null
+++ b/htsworkflow/util/rdfjsonld.py
@@ -0,0 +1,33 @@
+import RDF
+from pyld import jsonld
+
+def load_into_model(model, json_data):
+    '''Given a PyLD dictionary, load its statements into our Redland model
+    '''
+    json_graphs = jsonld.to_rdf(json_data)
+    for graph in json_graphs:
+        for triple in json_graphs[graph]:
+            stmt = triple_to_statement(triple)
+            model.add_statement(stmt) #, graph_context)
+
+def triple_to_statement(triple):
+    '''Convert PyLD triple dictionary to a librdf statement
+    '''
+    s = to_node(triple['subject'])
+    p = to_node(triple['predicate'])
+    o = to_node(triple['object'])
+    return RDF.Statement(s, p, o)
+
+def to_node(item):
+    '''Convert a PyLD node to a Redland node'''
+    nodetype = item['type']
+    value = item['value']
+    datatype = item.get('datatype', None)
+
+    if nodetype == 'blank node':
+        return RDF.Node(blank=value)
+    elif nodetype == 'IRI':
+        return RDF.Node(uri_string=str(value))
+    else:
+        return RDF.Node(literal=unicode(value).encode('utf-8'),
+                        datatype=RDF.Uri(datatype))

diff --git a/htsworkflow/util/test/test_rdfjsonld.py b/htsworkflow/util/test/test_rdfjsonld.py
new file mode 100644 (file)
index 0000000..8e501ba
--- /dev/null
+++ b/htsworkflow/util/test/test_rdfjsonld.py
@@ -0,0 +1,56 @@
+from unittest2 import TestCase, TestSuite, defaultTestLoader, skip
+
+from htsworkflow.util.rdfjsonld import load_into_model, to_node, triple_to_statement
+from htsworkflow.util.rdfhelp import get_model
+
+jstatement = {
+    'object': {'datatype': u'http://www.w3.org/2001/XMLSchema#dateTime',
+                'type': 'literal',
+                'value': '1940-10-09'},
+    'predicate': {'type': 'IRI',
+                    'value': u'http://schema.org/birthDate'},
+    'subject': {'type': 'blank node',
+                'value': '_:a'}
+}
+doc = {
+  "@context": "http://json-ld.org/contexts/person.jsonld",
+  "@id": "http://dbpedia.org/resource/John_Lennon",
+  "name": "John Lennon",
+  "born": "1940-10-09",
+  "spouse": "http://dbpedia.org/resource/Cynthia_Lennon"
+}
+
+class TestJsonLD(TestCase):
+    def test_to_node(self):
+        obj = to_node(jstatement['object'])
+        self.assertTrue(obj.is_literal())
+        self.assertEqual(str(obj), '1940-10-09')
+        pred = to_node(jstatement['predicate'])
+        self.assertTrue(pred.is_resource())
+        self.assertEqual(str(pred.uri), jstatement['predicate']['value'])
+        subj = to_node(jstatement['subject'])
+        self.assertTrue(subj.is_blank())
+
+    def test_to_statement(self):
+        stmt = triple_to_statement(jstatement)
+        self.assertTrue(stmt.object.is_literal())
+        self.assertEqual(str(stmt.object), '1940-10-09')
+        self.assertTrue(stmt.predicate.is_resource())
+        self.assertEqual(str(stmt.predicate.uri), jstatement['predicate']['value'])
+        self.assertTrue(stmt.subject.is_blank())
+
+    def test_load_model(self):
+        model = get_model(use_contexts=False)
+        self.assertEqual(len(model), 0)
+        load_into_model(model, doc)
+        self.assertEqual(len(model), 3)
+
+def suite():
+    suite = TestSuite()
+    suite.addTests(
+        defaultTestLoader.loadTestsFromTestCase(TestJsonLD))
+    return suite
+
+if __name__ == "__main__":
+    from unittest2 import main
+    main(defaultTest='suite')

diff --git a/setup.py b/setup.py
index 2d63df10ef7a35c623d0a0e219cf2c26571a1b6d..f63f1e10b587b4fe7001f6ecc4962780ba2efd70 100644 (file)
--- a/setup.py
+++ b/setup.py
@@ -36,6 +36,7 @@ setup(
                       'benderjab >= 0.2',
                       'httplib2',
                       'keyring',
+                      'PyLD',
                       # This dependency is redland librdf, which doesn't have a public egg
                       #'librdf >= 1.0.14',
     ],