N-Quads parsing error during normalization

[br41nlet]

Overview

I've ran into an issue trying to normalize N-Quads using URDNA2015 normalization from jsonld library.

pyld.jsonld.JsonLdError: ('Could not convert input to RDF dataset before normalization.',)
Type: jsonld.NormalizeError
Cause: ('Error while parsing N-Quads invalid quad.',)
Type: jsonld.ParseError

Details

In dkg.js we're normalizing N-Quads using the following function:

async toNQuads(content, inputFormat) {
    const options = {
        algorithm: 'URDNA2015',
        format: 'application/n-quads',
    };

    if (inputFormat) {
        options.inputFormat = inputFormat;
    }

    const canonized = await jsonld.canonize(content, options);

    return canonized.split('\n').filter((x) => x !== '');
}

I've tried to reproduce the same logic in dkg.py, but I've ran into issues trying to normalized N-Quads (JSON-LD works fine). It may be either wrong usage of the library from my side or bug in the jsonld as it seems it's not supported anymore.

Python normalization function:

def normalize_dataset(
    dataset: JSONLD | NQuads,
    input_format: Literal["JSON-LD", "N-Quads"] = "JSON-LD",
) -> NQuads:
    normalization_options = {
        "algorithm": "URDNA2015",
        "format": "application/n-quads",
    }

    match input_format.lower():
        case "json-ld" | "jsonld":
            pass
        case "n-quads" | "nquads":
            normalization_options["inputFormat"] = "application/n-quads"
        case _:
            raise DatasetInputFormatNotSupported(
                f"Dataset input format isn't supported: {input_format}. "
                "Supported formats: JSON-LD / N-Quads."
            )

    n_quads = jsonld.normalize(dataset, normalization_options)
    assertion = [quad for quad in n_quads.split("\n") if quad]

    if not assertion:
        raise InvalidDataset("Invalid dataset, no quads were extracted.")

    return assertion

[zsculac]

We'll look into this because this version of the normalize_dataset function is still in use today.