Hello Donny, Perhaps you're in need of JSON-LD (https://json-ld.org/)? Check out how to use that in RDFLib with the examples at:
https://rdflib.readthedocs.io/en/stable/apidocs/rdflib.plugins.parsers.html#module-rdflib.plugins.parsers.jsonld and: https://rdflib.readthedocs.io/en/stable/apidocs/rdflib.plugins.serializers.html#module-rdflib.plugins.serializers.jsonld Cheers, Niklas On Fri, Oct 15, 2021 at 8:19 PM Donny Winston <[email protected]> wrote: > Hi all, > > Perhaps this is hidden somewhere in the rdflib repo and I wasn’t able to > find it, but I found myself wanting to encode rdflib.term.Literal values to > JSON as e.g. {“value”: literal.value, “datatype”: literal.datatype, …}. I > ended up adapting the advice of a SO post. Here is my answer on SO with an > rdflib example: > [https://stackoverflow.com/a/69588931/1820042](https://stackoverflow.com/a/69588931/1820042) > . > > Also reproduced below. I hope folks find it useful. Also feel free to > point out where this has already been done, and I’ll pip install that > instead of my custom code! > > from json.encoder import (_make_iterencode, JSONEncoder, > encode_basestring_ascii, INFINITY, > encode_basestring) > class CustomObjectEncoder(JSONEncoder): > > def iterencode(self, o, _one_shot=False): > """Encode the given object and yield each string > representation as available. > > For example:: > > for chunk in JSONEncoder().iterencode(bigobject): > mysocket.write(chunk) > > Change from json.encoder.JSONEncoder.iterencode is setting > _one_shot=False and isinstance=self.isinstance > in call to `_make_iterencode`. > And not using `c_make_encoder`. > > """ > if self.check_circular: > markers = {} > else: > markers = None > if self.ensure_ascii: > _encoder = encode_basestring_ascii > else: > _encoder = encode_basestring > > def floatstr(o, allow_nan=self.allow_nan, > _repr=float.__repr__, _inf=INFINITY, _neginf=-INFINITY): > # Check for specials. Note that this type of test is processor > # and/or platform-specific, so do tests which don't depend on the > # internals. > > if o != o: > text = 'NaN' > elif o == _inf: > text = 'Infinity' > elif o == _neginf: > text = '-Infinity' > else: > return _repr(o) > > if not allow_nan: > raise ValueError( > "Out of range float values are not JSON compliant: " + > repr(o)) > > return text > > _iterencode = _make_iterencode( > markers, self.default, _encoder, self.indent, floatstr, > self.key_separator, self.item_separator, self.sort_keys, > self.skipkeys, _one_shot=False, isinstance=self.isinstance) > return _iterencode(o, 0) > > Example subclass: > > import datetime > from rdflib.term import Literal, BNode > class RDFTermEncoder(CustomObjectEncoder): > def isinstance(self, o, cls): > if isinstance(o, (Literal, BNode)): > return False > return isinstance(o, cls) > def default(self, o): > if isinstance(o, Literal): > rv = {"value": o.value} > if o.datatype is not None: > rv["datatype"] = o.datatype > if o.language is not None: > rv["lang"] = o.language > return rv > if isinstance(o, BNode): > return "http://localhost/bnode/"; + str(o) > if isinstance(o, datetime.datetime): > return o.isoformat() > if isinstance(o, datetime.date): > return str(o) > # Let the base class default method raise the TypeError > return super().default(o) > > I just used this successfully for my work as > > db_json = json.loads(json.dumps(db_custom, cls=RDFTermEncoder)) > > Best, > Donny > > — > Donny Winston, PhD (he/him/his) | Polyneme LLC > https://donnywinston.com | https://polyneme.xyz > > If I’ve emailed you, I’d love to speak with you. > Schedule a meeting (15min+): https://meet.polyneme.xyz > > -- > http://github.com/RDFLib > --- > You received this message because you are subscribed to the Google Groups > "rdflib-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/rdflib-dev/5a70d567-652c-45da-b500-7776447210dd%40www.fastmail.com > <https://groups.google.com/d/msgid/rdflib-dev/5a70d567-652c-45da-b500-7776447210dd%40www.fastmail.com?utm_medium=email&utm_source=footer> > . > -- http://github.com/RDFLib --- You received this message because you are subscribed to the Google Groups "rdflib-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rdflib-dev/CADjV5jeHfZUZgYnABPZoJxgJxxouLcvODAXXyaYb-RYx7W-aVw%40mail.gmail.com.
