def toPython_decimal_test():
"""docstring for toPython"""
# test a normal iso
d = Literal('.1', datatype=XSD.decimal).toPython()
assert isinstance(d, Decimal)
payments = [
Literal(s, datatype=XSD.decimal) for s in '.1 .1 .1 -.3'.split()
]
assert sum([payment.toPython() for payment in payments]) == 0
def filter_by(cls, **kwargs):
"""Class method returns a generator over classs instances
meeting the kwargs conditions.
Each keyword must be a class descriptor
filter by RDF.type == cls.rdf_type is implicit
Order helps, the first keyword should be the most restrictive
"""
filters = []
for key, value in kwargs.items():
pred = cls._getdescriptor(key).pred
# try to make the value be OK for the triple query as an object
if isinstance(value, Identifier):
obj = value
else:
obj = Literal(value)
filters.append((pred, obj))
# make sure we filter by type
if not (RDF.type, cls.rdf_type) in filters:
filters.append((RDF.type, cls.rdf_type))
pred, obj = filters[0]
log.debug("Checking %s, %s" % (pred, obj))
for sub in cls.db.subjects(pred, obj):
log.debug("maybe %s" % sub)
for pred, obj in filters[1:]:
log.debug("Checking %s, %s" % (pred, obj))
try:
cls.db.triples((sub, pred, obj)).next()
except:
log.warn("No %s" % sub)
break
else:
yield cls(sub)
def get_by(cls, **kwargs):
"""Class Method, returns a single instance of the class
by a single kwarg. the keyword must be a descriptor of the
class.
example:
.. code-block:: python
bigBlue = Company.get_by(symbol='IBM')
:Note:
the keyword should map to an rdf predicate
that is of type owl:InverseFunctional"""
if len(kwargs) != 1:
raise ValueError("get_by wanted exactly 1 but got %i args\n" +
"Maybe you wanted filter_by" % (len(kwargs)))
key, value = kwargs.items()[0]
if isinstance(value, (URIRef, BNode, Literal)):
o = value
else:
o = Literal(value)
pred = cls._getdescriptor(key).pred
uri = cls.db.value(None, pred, o)
if uri:
return cls(uri)
else:
raise LookupError("%s = %s not found" % (key, value))
def toPython_datetime_test():
"""docstring for toPython"""
# test a normal iso
d = Literal('2008-02-09T10:46:29', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
d = Literal('2008-02-09T10:46:29Z', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
d = Literal('2008-02-09T10:46:29-07:00', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
d = Literal('2008-02-09T10:46:29.1', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
d = Literal('2008-02-09T10:46:29.123', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
d = Literal('2008-02-09T10:46:29.123456', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)
# test a normal iso with fractional seconds
d = Literal('2008-02-09 10:46:29', datatype=XSD.dateTime).toPython()
assert isinstance(d, datetime)