RDFLib
RDFLib is a pure Python package for working with RDF. RDFLib contains most things you need to work with RDF, including:
- parsers and serializers for RDF/XML, N3, NTriples, N-Quads, Turtle, TriX, Trig and JSON-LD (via a plugin).
- a Graph interface which can be backed by any one of a number of Store implementations
- store implementations for in-memory storage and persistent storage on top of the Berkeley DB
- a SPARQL 1.1 implementation - supporting SPARQL 1.1 Queries and Update statements
RDFlib Family of packages
The RDFlib community maintains many RDF-related Python code repositories with different purposes. For example:
- rdflib - the rdflib core
- sparqlwrapper - a simple Python wrapper around a SPARQL service to remotely execute your queries
- pyLODE - An OWL ontology documentation tool using Python and templating, based on LODE.
- rdflib-jsonld - an rdflib plugin that is an implementation of JSON-LD
Please see the list for all packages/repositories here:
Installation
RDFLib may be installed with Python's package management tool pip:
$ pip install rdflib
Alternatively manually download the package from the Python Package
Index (PyPI) at https://pypi.python.org/pypi/rdflib
The current version of RDFLib is 5.0.0, see the CHANGELOG.md
file for what's new in this release.
Getting Started
RDFLib aims to be a pythonic RDF API. rdflib's main data object is a Graph which is a Python collection
of RDF Subject, Predicate, Object Triples:
To create graph and load it with RDF data from DBPedia then print the results:
import rdflib
g = rdflib.Graph()
g.load('http://dbpedia.org/resource/Semantic_Web')
for s, p, o in g:
print(s, p, o)
The components of the triples are URIs (resources) or Literals
(values).
URIs are grouped together by namespace, common namespaces are
included in RDFLib:
from rdflib.namespace import DC, DCTERMS, DOAP, FOAF, SKOS, OWL, RDF, RDFS, VOID, XMLNS, XSD
You can use them like this:
semweb = rdflib.URIRef('http://dbpedia.org/resource/Semantic_Web')
type = g.value(semweb, rdflib.RDFS.label)
Where rdflib.RDFS is the RDFS Namespace, graph.value returns an
object of the triple-pattern given (or an arbitrary one if more
exist).
Or like this, adding a triple to a graph g:
g.add((
rdflib.URIRef("http://example.com/person/nick"),
FOAF.givenName,
rdflib.Literal("Nick", datatype=XSD.string)
))
The triple (in n-triples notation) <http://example.com/person/nick> <http://xmlns.com/foaf/0.1/givenName> "Nick"^^<http://www.w3.org/2001/XMLSchema#string> .
is created where the property FOAF.giveName is the URI <http://xmlns.com/foaf/0.1/givenName> and XSD.string is the
URI <http://www.w3.org/2001/XMLSchema#string>.
You can bind namespaces to prefixes to shorten the URIs for RDF/XML, Turtle, N3, TriG, TriX & JSON-LD serializations:
g.bind("foaf", FOAF)
g.bind("xsd", XSD)
This will allow the n-triples triple above to be serialised like this:
print(g.serialize(format="turtle").decode("utf-8"))
With these results:
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
<http://example.com/person/nick> foaf:givenName "Nick"^^xsd:string .
New Namespaces can also be defined:
dbpedia = rdflib.Namespace('http://dbpedia.org/ontology/')
abstracts = list(x for x in g.objects(semweb, dbpedia['abstract']) if x.language=='en')
See also ./examples
Features
The library contains parsers and serializers for RDF/XML, N3,
NTriples, N-Quads, Turtle, TriX, RDFa and Microdata. JSON-LD parsing/serializing can be achieved using the
JSON-LD plugin.
The library presents a Graph interface which can be backed by
any one of a number of Store implementations.
This core RDFLib package includes store implementations for
in-memory storage and persistent storage on top of the Berkeley DB.
A SPARQL 1.1 implementation is included - supporting SPARQL 1.1 Queries and Update statements.
RDFLib is open source and is maintained on GitHub. RDFLib releases, current and previous
are listed on PyPI
Multiple other projects are contained within the RDFlib "family", see https://github.com/RDFLib/.
Documentation
See https://rdflib.readthedocs.io for our documentation built from the code.
Support
For general "how do I..." queries, please use https://stackoverflow.com and tag your question with rdflib.
Existing questions:
Releases
See https://rdflib.dev for the release schedule.
Contributing
rdflib survives and grows via user contributions! Please consider lodging Pull Requests here:
You can also raise issues here:
Contacts
If you want to contact the rdflib maintainers, please do so via the rdflib-dev mailing list: