Source code for rdflib.plugins.serializers.nt

N-Triples RDF graph serializer for RDFLib.
See <> for details about the
from rdflib.term import Literal
from rdflib.serializer import Serializer
from rdflib.py3compat import b

import warnings
import codecs

__all__ = ['NTSerializer']

[docs]class NTSerializer(Serializer): """ Serializes RDF graphs to NTriples format. """
[docs] def __init__(self, store): Serializer.__init__(self, store) self.encoding = 'ascii' # n-triples are ascii encoded
[docs] def serialize(self, stream, base=None, encoding=None, **args): if base is not None: warnings.warn("NTSerializer does not support base.") if encoding is not None: warnings.warn("NTSerializer does not use custom encoding.") encoding = self.encoding for triple in stream.write(_nt_row(triple).encode(self.encoding, "_rdflib_nt_escape")) stream.write(b("\n"))
class NT11Serializer(NTSerializer): """ Serializes RDF graphs to RDF 1.1 NTriples format. Exactly like nt - only utf8 encoded. """ def __init__(self, store): Serializer.__init__(self, store) # default to utf-8 def _nt_row(triple): if isinstance(triple[2], Literal): return u"%s %s %s .\n" % ( triple[0].n3(), triple[1].n3(), _quoteLiteral(triple[2])) else: return u"%s %s %s .\n" % (triple[0].n3(), triple[1].n3(), triple[2].n3()) def _quoteLiteral(l): ''' a simpler version of term.Literal.n3() ''' encoded = _quote_encode(l) if l.language: if l.datatype: raise Exception("Literal has datatype AND language!") return '%s@%s' % (encoded, l.language) elif l.datatype: return '%s^^<%s>' % (encoded, l.datatype) else: return '%s' % encoded def _quote_encode(l): return '"%s"' % l.replace('\\', '\\\\')\ .replace('\n', '\\n')\ .replace('"', '\\"')\ .replace('\r', '\\r') def _nt_unicode_error_resolver(err): """ Do unicode char replaces as defined in """ def _replace_single(c): c = ord(c) fmt = u'\\u%04X' if c <= 0xFFFF else u'\\U%08X' return fmt % c string = err.object[err.start:err.end] return ( "".join( _replace_single(c) for c in string ), err.end ) codecs.register_error('_rdflib_nt_escape', _nt_unicode_error_resolver)