n3 parser can assign repeated bnode id strings for separate bnodes #305
Labels
bug
Something isn't working
Milestone
Comments
|
Well spotted - did this actually happen for you? |
|
And actually, if we anyway produce a uuid bnode ID, we can just as well just use |
|
Yes, it happened during a rehearsal for a live theater show :) I have a fancy RDF-based shared storage for a bunch of lighting tools. I reread from n3 files a lot, and eventually I started hitting this issue regularly. I think you're right about the possibility of calling BNode(). It might be slightly useful during debugging for the bnodes from one parse to have sequential identifiers (the "f%sb%s" thing), but even if we wanted to maintain that, we should move it closer to the other BNode code. Probably one uuid for the whole process and then a very global counter would work well-- faster than running uuids all the time, and whenever you parse a graph, you'll get mostly coherent sequences of ids. |
|
++ a very global counter would work well If I understand your proposal correctly, wouldn't that need to be shared across threads / processes? |
|
i added the fix proposed by @drewp, we can think of centralising it later :) |
mamash
pushed a commit
to TritonDataCenter/pkgsrc-wip
that referenced
this issue
Feb 15, 2014
Update package 2013/12/31 RELEASE 4.1 ====================== This is a new minor version RDFLib, which includes a handful of new features: * A TriG parser was added (we already had a serializer) - it is up-to-date wrt. to the newest spec from: http://www.w3.org/TR/trig/ * The Turtle parser was made up to date wrt. to the latest Turtle spec. * Many more tests have been added - RDFLib now has over 2000 (passing!) tests. This is mainly thanks to the NT, Turtle, TriG, NQuads and SPARQL test-suites from W3C. This also included many fixes to the nt and nquad parsers. * ```ConjunctiveGraph``` and ```Dataset``` now support directly adding/removing quads with ```add/addN/remove``` methods. * ```rdfpipe``` command now supports datasets, and reading/writing context sensitive formats. * Optional graph-tracking was added to the Store interface, allowing empty graphs to be tracked for Datasets. The DataSet class also saw a general clean-up, see: RDFLib/rdflib#309 * After long deprecation, ```BackwardCompatibleGraph``` was removed. Minor enhancements/bugs fixed: ------------------------------ * Many code samples in the documentation were fixed thanks to @PuckCh * The new ```IOMemory``` store was optimised a bit * ```SPARQL(Update)Store``` has been made more generic. * MD5 sums were never reinitialized in ```rdflib.compare``` * Correct default value for empty prefix in N3 [#312]RDFLib/rdflib#312 * Fixed tests when running in a non UTF-8 locale [#344]RDFLib/rdflib#344 * Prefix in the original turtle have an impact on SPARQL query resolution [#313]RDFLib/rdflib#313 * Duplicate BNode IDs from N3 Parser [#305]RDFLib/rdflib#305 * Use QNames for TriG graph names [#330]RDFLib/rdflib#330 * \uXXXX escapes in Turtle/N3 were fixed [#335]RDFLib/rdflib#335 * A way to limit the number of triples retrieved from the ```SPARQLStore``` was added [#346]RDFLib/rdflib#346 * Dots in localnames in Turtle [#345]RDFLib/rdflib#345 [#336]RDFLib/rdflib#336 * ```BNode``` as Graph's public ID [#300]RDFLib/rdflib#300 * Introduced ordering of ```QuotedGraphs``` [#291]RDFLib/rdflib#291 2013/05/22 RELEASE 4.0.1 ======================== Following RDFLib tradition, some bugs snuck into the 4.0 release. This is a bug-fixing release: * the new URI validation caused lots of problems, but is nescessary to avoid ''RDF injection'' vulnerabilities. In the spirit of ''be liberal in what you accept, but conservative in what you produce", we moved validation to serialisation time. * the ```rdflib.tools``` package was missing from the ```setup.py``` script, and was therefore not included in the PYPI tarballs. * RDF parser choked on empty namespace URI [#288](RDFLib/rdflib#288) * Parsing from ```sys.stdin``` was broken [#285](RDFLib/rdflib#285) * The new IO store had problems with concurrent modifications if several graphs used the same store [#286](RDFLib/rdflib#286) * Moved HTML5Lib dependency to the recently released 1.0b1 which support python3 2013/05/16 RELEASE 4.0 ====================== This release includes several major changes: * The new SPARQL 1.1 engine (rdflib-sparql) has been included in the core distribution. SPARQL 1.1 queries and updates should work out of the box. * SPARQL paths are exposed as operators on ```URIRefs```, these can then be be used with graph.triples and friends: ```py # List names of friends of Bob: g.triples(( bob, FOAF.knows/FOAF.name , None )) # All super-classes: g.triples(( cls, RDFS.subClassOf * '+', None )) ``` * a new ```graph.update``` method will apply SPARQL update statements * Several RDF 1.1 features are available: * A new ```DataSet``` class * ```XMLLiteral``` and ```HTMLLiterals``` * ```BNode``` (de)skolemization is supported through ```BNode.skolemize```, ```URIRef.de_skolemize```, ```Graph.skolemize``` and ```Graph.de_skolemize``` * Handled of Literal equality was split into lexical comparison (for normal ```==``` operator) and value space (using new ```Node.eq``` methods). This introduces some slight backwards incomaptible changes, but was necessary, as the old version had inconsisten hash and equality methods that could lead the literals not working correctly in dicts/sets. The new way is more in line with how SPARQL 1.1 works. For the full details, see: https://github.com/RDFLib/rdflib/wiki/Literal-reworking * Iterating over ```QueryResults``` will generate ```ResultRow``` objects, these allow access to variable bindings as attributes or as a dict. I.e. ```py for row in graph.query('select ... ') : print row.age, row["name"] ``` * "Slicing" of Graphs and Resources as syntactic sugar: ([#271](RDFLib/rdflib#271)) ```py graph[bob : FOAF.knows/FOAF.name] -> generator over the names of Bobs friends ``` * The ```SPARQLStore``` and ```SPARQLUpdateStore``` are now included in the RDFLib core * The documentation has been given a major overhaul, and examples for most features have been added. Minor Changes: -------------- * String operations on URIRefs return new URIRefs: ([#258](RDFLib/rdflib#258)) ```py >>> URIRef('http://example.org/')+'test rdflib.term.URIRef('http://example.org/test') ``` * Parser/Serializer plugins are also found by mime-type, not just by plugin name: ([#277](RDFLib/rdflib#277)) * ```Namespace``` is no longer a subclass of ```URIRef``` * URIRefs and Literal language tags are validated on construction, avoiding some "RDF-injection" issues ([#266](RDFLib/rdflib#266)) * A new memory store needs much less memory when loading large graphs ([#268](RDFLib/rdflib#268)) * Turtle/N3 serializer now supports the base keyword correctly ([#248](RDFLib/rdflib#248)) * py2exe support was fixed ([#257](RDFLib/rdflib#257)) * Several bugs in the TriG serializer were fixed * Several bugs in the NQuads parser were fixed
This was referenced Jan 16, 2017
This was referenced Mar 16, 2017
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
I don't have time to make a good writeup right now, but there's a serious problem in rdflib/plugins/parsers/notation3.py where it will in some cases assign the same 'random' string to two bnodes, and then your data gets corrupt. Below shows my fix-- look for the triple ###.
A test case might try reading the same file with bnodes a few times, trying to make the parser objects land in the same place in memory.
changes in rdflib/plugins/parsers/notation3.py
The text was updated successfully, but these errors were encountered: