N-triples parser not in line with N-triples specification

[csae8092]

while trying to parse an n-triples with rdflib version 4.2.2

rdflib.Graph().parse(data='<https://arche-curation.acdh-dev.oeaw.ac.at/api/8458> <https://vocabs.acdh.oeaw.ac.at/schema#hasIdentifier> <make\\u0020me> .', format='nt')

an error is thrown:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 140, in parse
    self.parseline()
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 195, in parseline
    object = self.object()
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 228, in object
    objt = self.uriref() or self.nodeid() or self.literal()
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 235, in uriref
    uri = self.eat(r_uriref).group(1)
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 210, in eat
    raise ParseError("Failed to eat %s at %s" % (pattern.pattern, self.line))
rdflib.plugins.parsers.ntriples.ParseError: Failed to eat <([^:]+:[^\s"<>]+)> at <make\u0020me> .

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/rdflib/graph.py", line 1043, in parse
    parser.parse(source, self, **args)
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/nt.py", line 26, in parse
    parser.parse(f)
  File "/usr/lib/python3/dist-packages/rdflib/plugins/parsers/ntriples.py", line 142, in parse
    raise ParseError("Invalid line: %r" % self.line)
rdflib.plugins.parsers.ntriples.ParseError: Invalid line: '<make\\u0020me> .'

The traceback suggests the object-URI has to match the <([^:]+:[^\s"<>]+)> regex which is not in line with the n-triples specification (8th statement of the https://www.w3.org/TR/n-triples/#n-triples-grammar) which doesn't require the IRIREF to contain a semicolon and allows it to contain unicode escape sequences.

[ashleysommer]

This is a duplicate of #1245

In 2004 the first example of an NTriples grammar was published in the RDF-testcases v1.0 2004 document here: https://www.w3.org/TR/2004/REC-rdf-testcases-20040210

A python reference implementation of that grammar was written by the W3C and became incorporated into RDFlib. That grammar became widespread and went on to become what we call NTriples 1.0.

In 2014 the NTriples v1.1 format specification was published: (the one you linked to: https://www.w3.org/TR/n-triples/)
but nobody has yet written a v1.1-compliant NTriples Parser for RDFLib.

[aucampia]

@gjhiggins should this not be a bug?

[ghost]

Rereading the comments, yes it should be. I mis-interpreted "this issue should be solved" as "should have been solved by " instead of "will be solved by". The example given still fails and PR #1222 is still outstanding.

[aucampia]

• Converted to N-triples parser not in line with N-triples specification #1835