1 """Helper features for working with librdf
9 logger = logging.getLogger(__name__)
11 # standard ontology namespaces
12 owlNS = RDF.NS('http://www.w3.org/2002/07/owl#')
13 dublinCoreNS = RDF.NS("http://purl.org/dc/elements/1.1/")
14 rdfNS = RDF.NS("http://www.w3.org/1999/02/22-rdf-syntax-ns#")
15 rdfsNS= RDF.NS("http://www.w3.org/2000/01/rdf-schema#")
16 xsdNS = RDF.NS("http://www.w3.org/2001/XMLSchema#")
19 submissionOntology = RDF.NS("http://jumpgate.caltech.edu/wiki/UcscSubmissionOntology#")
20 dafTermOntology = RDF.NS("http://jumpgate.caltech.edu/wiki/UcscDaf#")
21 libraryOntology = RDF.NS("http://jumpgate.caltech.edu/wiki/LibraryOntology#")
22 inventoryOntology = RDF.NS("http://jumpgate.caltech.edu/wiki/InventoryOntology#")
23 submissionLog = RDF.NS("http://jumpgate.caltech.edu/wiki/SubmissionsLog/")
25 def sparql_query(model, query_filename):
26 """Execute sparql query from file
28 logger.info("Opening: %s" % (query_filename,))
29 query_body = open(query_filename,'r').read()
30 query = RDF.SPARQLQuery(query_body)
31 results = query.execute(model)
34 for k,v in row.items()[::-1]:
35 print "{0}: {1}".format(k,v)
39 def blankOrUri(value=None):
43 elif type(value) in types.StringTypes:
44 node = RDF.Node(uri_string=value)
45 elif isinstance(value, RDF.Node):
51 def toTypedNode(value):
52 if type(value) == types.BooleanType:
53 value_type = xsdNS['boolean'].uri
58 elif type(value) in (types.IntType, types.LongType):
59 value_type = xsdNS['decimal'].uri
60 value = unicode(value)
61 elif type(value) == types.FloatType:
62 value_type = xsdNS['float'].uri
63 value = unicode(value)
66 value = unicode(value)
68 if value_type is not None:
69 node = RDF.Node(literal=value, datatype=value_type)
71 node = RDF.Node(literal=unicode(value).encode('utf-8'))
74 def fromTypedNode(node):
78 value_type = str(node.literal_value['datatype'])
79 # chop off xml schema declaration
80 value_type = value_type.replace(str(xsdNS[''].uri),'')
81 literal = node.literal_value['string']
82 literal_lower = literal.lower()
84 if value_type == 'boolean':
85 if literal_lower in ('1', 'yes', 'true'):
87 elif literal_lower in ('0', 'no', 'false'):
90 raise ValueError("Unrecognized boolean %s" % (literal,))
91 elif value_type == 'decimal' and literal.find('.') == -1:
93 elif value_type in ('decimal', 'float', 'double'):
95 elif value_type in ('string'):
97 elif value_type in ('dateTime'):
98 raise NotImplemented('need to parse isoformat date-time')
103 def get_model(model_name=None, directory=None):
104 if directory is None:
105 directory = os.getcwd()
107 if model_name is None:
108 storage = RDF.MemoryStorage()
109 logger.info("Using RDF Memory model")
111 options = "hash-type='bdb',dir='{0}'".format(directory)
112 storage = RDF.HashStorage(model_name,
114 logger.info("Using {0} with options {1}".format(model_name, options))
115 model = RDF.Model(storage)
119 def load_into_model(model, parser_name, filename, ns=None):
120 if not os.path.exists(filename):
121 raise IOError("Can't find {0}".format(filename))
123 data = open(filename, 'r').read()
124 load_string_into_model(model, parser_name, data, ns)
127 def load_string_into_model(model, parser_name, data, ns=None):
129 ns = "http://localhost/"
131 rdf_parser = RDF.Parser(name=parser_name)
132 rdf_parser.parse_string_into_model(model, data, ns)
135 def get_serializer(name='turtle'):
136 """Return a serializer with our standard prefixes loaded
138 writer = RDF.Serializer(name=name)
139 # really standard stuff
140 writer.set_namespace('owl', owlNS._prefix)
141 writer.set_namespace('rdf', rdfNS._prefix)
142 writer.set_namespace('rdfs', rdfsNS._prefix)
143 writer.set_namespace('xsd', xsdNS._prefix)
145 # should these be here, kind of specific to an application
146 writer.set_namespace('libraryOntology', libraryOntology._prefix)
147 writer.set_namespace('ucscSubmission', submissionOntology._prefix)
148 writer.set_namespace('ucscDaf', dafTermOntology._prefix)