2023-02-26 20:25:35 -08:00

80 lines
2.2 KiB
Python

"""Read RDF files."""
from pathlib import Path
from typing import Any, Dict, List, Optional
from llama_index.readers.base import BaseReader
from llama_index.readers.schema.base import Document
class RDFReader(BaseReader):
"""RDF reader."""
def __init__(
self,
*args: Any,
**kwargs: Any,
) -> None:
"""Initialize loader."""
super().__init__(*args, **kwargs)
from rdflib import Graph, URIRef
from rdflib.namespace import RDF, RDFS
self.Graph = Graph
self.RDF = RDF
self.RDFS = RDFS
def fetch_labels(self, uri: Any, graph: Any, lang: str):
"""Fetch all labels of a URI by language."""
return list(
filter(
lambda x: x.language in [lang, None],
graph.objects(uri, self.RDFS.label),
)
)
def fetch_label_in_graphs(self, uri: Any, lang: str = "en"):
"""Fetch one label of a URI by language from the local or global graph."""
labels = self.fetch_labels(uri, self.g_local, lang)
if len(labels) > 0:
return labels[0].value
labels = self.fetch_labels(uri, self.g_global, lang)
if len(labels) > 0:
return labels[0].value
raise Exception(f"Label not found for: {uri}")
def load_data(
self, file: Path, extra_info: Optional[Dict] = None
) -> List[Document]:
"""Parse file."""
lang = extra_info["lang"] if extra_info is not None else "en"
self.g_local = self.Graph()
self.g_local.parse(file)
self.g_global = self.Graph()
self.g_global.parse(str(self.RDF))
self.g_global.parse(str(self.RDFS))
text_list = []
for s, p, o in self.g_local:
if p == self.RDFS.label:
continue
triple = (
f"<{self.fetch_label_in_graphs(s, lang=lang)}> "
f"<{self.fetch_label_in_graphs(p, lang=lang)}> "
f"<{self.fetch_label_in_graphs(o, lang=lang)}>"
)
text_list.append(triple)
text = "\n".join(text_list)
return [Document(text, extra_info=extra_info)]