def _parseRDFFromString(contents, baseuri, type='unknown', scope=None,
options=None):
from vesper.data import base
if scope is None: scope = '' #workaround 4suite bug
options = options or {}
if type.startswith('http://rx4rdf.sf.net/ns/wiki#rdfformat-'):
type = type.split('-', 1)[1]
if isinstance(contents, unicode):
contents = contents.encode('utf8')
try:
while type == 'unknown':
if isinstance(contents, (list, tuple)):
if not contents:
return contents, 'statements'
if isinstance(contents[0], (tuple, BaseStatement)):
return contents, 'statements' #looks like already a list of statements
#otherwise assume pjson
type='pjson'
break
elif isinstance(contents, dict):
type='pjson' #assume pjson
break
startcontents = contents[:256].lstrip()
if not startcontents: #empty
return [], 'statements'
if startcontents[0] in '{[':
type='pjson' #assume pjson
break
else:
from vesper import multipartjson
if multipartjson.looks_like_multipartjson(startcontents):
type = 'mjson'
break
try:
from vesper.utils import htmlfilter
ns, prefix, local = htmlfilter.getRootElementName(contents)
if ns == 'http://www.w3.org/1999/02/22-rdf-syntax-ns#':
type = 'rdfxml'
elif local == 'rx':
type = 'rxml_xml'
elif ns == 'http://purl.org/atom/ns#' or local == 'rss':
type = "rss-tag-soup"
else:
raise ParseException(
"RDF parse error: Unsupported XML vocabulary: " + local)
except:
#hmmm, try our NTriples parser
try:
#convert generator to list to force parsing now
return list(NTriples2Statements(
StringIO.StringIO(contents), scope,
baseuri, **options))
except:
raise ParseException("unrecognized or invalid file contents")
if type in ['ntriples', 'ntjson']:
#use our parser
return NTriples2Statements(StringIO.StringIO(contents), scope,
baseuri, **options), type
elif type == 'rss-tag-soup':
try: #only redland's parser supports these
import RDF
parser=RDF.Parser(type)
stream = parser.parse_string_as_stream(contents, baseuri)
return base.redland2Statements(stream, scope), type
except ImportError:
raise ParseException("RDF parse error: "+ type+
" is only supported by Redland, which isn't installed")
elif type == 'rdfxml' or type == 'turtle':
if rdfParser:
return rdfParser(contents, baseuri, type, scope)
try:
return _parseRDFWithRdfLib(contents, baseuri, type, scope)
except ImportError:
try: #try redland's parser
return _parseRDFWithRdfLib(contents, baseuri, type, scope)
except ImportError:
raise ParseException("no %s parser installed" % type)
elif type == 'json':
return _parseRDFJSON(contents, scope), type
elif type == 'pjson' or type == 'yaml' or type == 'mjson':
from vesper import pjson
if isinstance(contents, str):
if type == 'yaml':
import yaml
contents = yaml.safe_load(contents)
elif type == 'mjson':
from vesper import multipartjson
content = multipartjson.loads(contents, False)
else:
contents = json.loads(contents)
options['scope'] = scope
#XXX generateBnode doesn't detect collisions, maybe gen UUID instead
if 'generateBnode' not in options:
options['generateBnode']='uuid'
if not contents:
return [], type
stmts = pjson.tostatements(contents, **options), type
return stmts
else:
raise ParseException('unsupported type: ' + type)
except ParseException:
raise
except: #an unexpected Exception
raise ParseException("error parsing "+type)
