def parse(self, data, _format=None):
'''
Parses and RDF graph serialization and into the class graph
It calls the rdflib parse function with the provided data and format.
Data is a string with the serialized RDF graph (eg RDF/XML, N3
... ). By default RF/XML is expected. The optional parameter _format
can be used to tell rdflib otherwise.
It raises a ``RDFParserException`` if there was some error during
the parsing.
Returns nothing.
'''
_format = url_to_rdflib_format(_format)
if _format == 'pretty-xml':
_format = 'xml'
try:
self.g.parse(data=data, format=_format)
# Apparently there is no single way of catching exceptions from all
# rdflib parsers at once, so if you use a new one and the parsing
# exceptions are not cached, add them here.
# PluginException indicates that an unknown format was passed.
except (SyntaxError, xml.sax.SAXParseException,
rdflib.plugin.PluginException, TypeError), e:
raise RDFParserException(e)
def serialize_dataset(self, dataset_dict, _format='xml'):
'''
Given a CKAN dataset dict, returns an RDF serialization
The serialization format can be defined using the `_format` parameter.
It must be one of the ones supported by RDFLib, defaults to `xml`.
Returns a string with the serialized dataset
'''
log.debug('Entrando en serialize_dataset')
self.graph_from_dataset(dataset_dict)
_format = url_to_rdflib_format(_format)
if _format == 'json-ld':
output = self.g.serialize(format=_format, auto_compact=True)
else:
output = self.g.serialize(format=_format)
return output
def serialize_catalog(self,
catalog_dict=None,
dataset_dicts=None,
_format='xml',
pagination_info=None):
'''
Returns an RDF serialization of the whole catalog
`catalog_dict` can contain literal values for the dcat:Catalog class
like `title`, `homepage`, etc. If not provided these would get default
values from the CKAN config (eg from `ckan.site_title`).
If passed a list of CKAN dataset dicts, these will be also serializsed
as part of the catalog.
**Note:** There is no hard limit on the number of datasets at this
level, this should be handled upstream.
The serialization format can be defined using the `_format` parameter.
It must be one of the ones supported by RDFLib, defaults to `xml`.
`pagination_info` may be a dict containing keys describing the results
pagination. See the `_add_pagination_triples()` method for details.
Returns a string with the serialized catalog
'''
log.debug('Entrando en serialize_catalog')
catalog_ref = self.graph_from_catalog(catalog_dict)
if dataset_dicts:
for dataset_dict in dataset_dicts:
dataset_ref = self.graph_from_dataset(dataset_dict)
self.g.add((catalog_ref, DCAT.dataset, dataset_ref))
if pagination_info:
self._add_pagination_triples(pagination_info)
_format = url_to_rdflib_format(_format)
output = self.g.serialize(format=_format)
return output