refactor: implement rapidfuzz

pyproject.toml

@@ -19,6 +19,7 @@ dependencies = [
     "python-multipart>=0.0.20",
     "rdflib>=7.1.4",
     "SPARQLWrapper>=2.0.0",
+    "rapidfuzz>=3.0.0",
 ]
 [dependency-groups]
 dev = [

src/strings2things/app/api/endpoints.py

@@ -3,36 +3,48 @@
 from fastapi import APIRouter, UploadFile, File, Form
 from fastapi.responses import Response
 from rdflib import Graph
-from src.strings2things.app.core.rdf_transformer import RDFTransformer
-from src.strings2things.app.core.ontology_manager import (
-    OntologyManager,
-)  # Assume this exists
-from src.strings2things.app.utils.rdf_utils import (
-    parse_rdf,
-    serialize_rdf,
-)  # Also assume or create
+from strings2things.app.core.rdf_transformer import RDFTransformer
+from strings2things.app.core.ontology_manager import OntologyManager
+from strings2things.app.utils.rdf_utils import parse_rdf, serialize_rdf
 import logging
 
 router = APIRouter()
 
 ontology_manager = OntologyManager()
 ontology_manager.load_ontologies()
 
-transformer = RDFTransformer(ontology_manager.get_label_map())
+# Keep transformer as a base instance
+base_label_map = ontology_manager.get_label_map()
 
 
 @router.post("/transform")
 async def transform_rdf(
-    file: UploadFile = File(...), serialization: str = Form("turtle")
+    file: UploadFile = File(...),
+    serialization: str = Form("turtle"),
+    fuzzy: bool = Form(False),  # <-- new parameter
+    fuzzy_threshold: int = Form(90),  # <-- configurable fuzzy matching threshold
 ) -> Response:
     """
     Accepts an RDF file upload, transforms it using the label map,
     and returns the modified RDF graph in the requested format.
+
+    Args:
+        file: The uploaded RDF file
+        serialization: Desired output RDF serialization (default: turtle)
+        fuzzy: Whether to use fuzzy matching (default: False)
+        threshold: Similarity threshold for fuzzy matching (0-100, default: 90)
     """
     content = await file.read()
 
     try:
         input_graph = parse_rdf(content)
+
+        transformer = RDFTransformer(
+            base_label_map,
+            fuzzy=fuzzy,
+            fuzzy_threshold=fuzzy_threshold,
+        )
+
         transformed_graph = transformer.transform(input_graph)
         serialized = serialize_rdf(transformed_graph, output_format=serialization)
 

src/strings2things/app/core/rdf_transformer.py

@@ -1,17 +1,45 @@
 # app/core/rdf_transformer.py
 """
 Transforms RDF graphs by replacing string literals with matching ontology IRIs.
+Supports exact and fuzzy matching (RapidFuzz).
 """
 
 from rdflib import Graph, Literal, URIRef
 from strings2things.app.core.transformation_log import TransformationLog
+from rapidfuzz import process
 
 
 class RDFTransformer:
-    def __init__(self, label_map: dict[str, str]):
+    def __init__(self, label_map: dict[str, str], fuzzy: bool, fuzzy_threshold: int = 90):
+        """
+        :param label_map: dict of {label -> IRI}
+        :param fuzzy_threshold: minimum score for fuzzy fallback
+        """
         self.label_map = label_map
+        self.fuzzy = fuzzy
+        self.fuzzy_threshold = fuzzy_threshold
         self.log = TransformationLog()
 
+    def _find_match(self, label: str) -> str | None:
+        """
+        Find an IRI for the given label.
+        First tries exact match, then falls back to fuzzy.
+        """
+        label = label.strip().lower()
+
+        # Exact match
+        if label in self.label_map:
+            return self.label_map[label]
+
+        # Fuzzy fallback
+        best = process.extractOne(label, self.label_map.keys())
+        if best:
+            match, score, _ = best
+            if score >= self.fuzzy_threshold:
+                return self.label_map[match]
+
+        return None
+
     def transform(self, input_graph: Graph) -> Graph:
         """
         Replace matching string literals in the RDF graph with IRIs.
@@ -20,29 +48,28 @@ def transform(self, input_graph: Graph) -> Graph:
         output_graph = Graph()
 
         for s, p, o in input_graph:
-            # if string matches object
             if isinstance(o, Literal) and isinstance(o.value, str):
-                label = o.value.strip().lower()
-                if label in self.label_map:
-                    iri = URIRef(self.label_map[label])
+                iri_str = self._find_match(o.value)
+                if iri_str:
+                    iri = URIRef(iri_str)
 
-                    # Retain original triple (to retain backward compatibility for now)
+                    # Retain original triple (for backward compatibility)
                     output_graph.add((s, p, o))
-                    output_graph.add(
-                        (iri, URIRef("http://wwww.example.org/thingOf"), o)
-                    )
-
+                    output_graph.add((iri, URIRef("http://wwww.example.org/thingOf"), o))
                     output_graph.add((s, p, iri))
 
                     self.log.add_entry(
                         subject=str(s),
                         predicate=str(p),
                         original_value=str(o),
                         replacement_iri=str(iri),
-                        reason="unambiguous match",
+                        reason="exact match"
+                        if o.value.strip().lower() in self.label_map
+                        else f"fuzzy match (threshold={self.fuzzy_threshold})",
                     )
                     continue
 
+            # If no match found → leave as-is
             output_graph.add((s, p, o))
             self.log.add_entry(
                 subject=str(s),
@@ -52,7 +79,7 @@ def transform(self, input_graph: Graph) -> Graph:
                 reason=(
                     "not a string literal"
                     if not isinstance(o, Literal)
-                    else "no match in label map"
+                    else "no match found"
                 ),
             )
 

tests/test_rdf_transformer.py

@@ -1,53 +1,70 @@
 import pytest
 from rdflib import Graph, URIRef, Literal, Namespace
 from strings2things.app.core.rdf_transformer import RDFTransformer
-from strings2things.app.core.transformation_log import TransformationLog
 
-EX = Namespace("http://example.org/")
+EX = Namespace("http://example.org/ontology#")
 
 
 @pytest.fixture
 def label_map():
+    # Ontology label map: canonical labels → IRIs
     return {
-        "geology": "http://example.org/ontology#Geology",
-        "biology": "http://example.org/ontology#Biology",
+        "geology": str(EX.Geology),
+        "biology": str(EX.Biology),
+        "physics": str(EX.Physics),
     }
 
 
 @pytest.fixture
 def input_graph():
     g = Graph()
-    g.add((EX.subj1, EX.hasCategory, Literal("Geology")))
-    g.add((EX.subj2, EX.hasCategory, Literal("UnknownLabel")))
-    g.add((EX.subj3, EX.hasValue, URIRef("http://example.org/someIRI")))
+    # Exact match example
+    g.add((EX.subj1, EX.hasCategory, Literal("geology")))
+
+    # Fuzzy match example (slightly misspelled)
+    g.add((EX.subj2, EX.hasCategory, Literal("biolgy")))
+
+    # Unknown label (should remain unchanged)
+    g.add((EX.subj3, EX.hasCategory, Literal("unknownlabel")))
+
+    # Non-literal value (should remain untouched)
+    g.add((EX.subj4, EX.hasValue, URIRef("http://example.org/someIRI")))
     return g
 
 
-def test_rdf_transformer(label_map, input_graph):
-    transformer = RDFTransformer(label_map)
+def test_rdf_transformer_combined(label_map, input_graph):
+    # Initialize transformer with fuzzy matching enabled
+    transformer = RDFTransformer(label_map, fuzzy=True, fuzzy_threshold=90)
     output_graph = transformer.transform(input_graph)
 
-    # --- Check graph triples ---
-    # Original triple must remain
-    assert (EX.subj1, EX.hasCategory, Literal("Geology")) in output_graph
+    # --- 1. Check graph triples ---
 
-    # Transformed triple must be present
-    expected_iri = URIRef("http://example.org/ontology#Geology")
-    assert (EX.subj1, EX.hasCategory, expected_iri) in output_graph
+    # Exact match: literal replaced by IRI
+    assert (EX.subj1, EX.hasCategory, URIRef("http://example.org/ontology#Geology")) in output_graph
 
-    # UnknownLabel should remain unchanged (no IRI added)
-    assert (EX.subj2, EX.hasCategory, Literal("UnknownLabel")) in output_graph
-    assert len([t for t in output_graph.triples((EX.subj2, EX.hasCategory, None))]) == 1
+    # Fuzzy match: literal replaced by IRI
+    assert (EX.subj2, EX.hasCategory, URIRef("http://example.org/ontology#Biology")) in output_graph
 
-    # Non-literals should remain untouched
-    assert (EX.subj3, EX.hasValue, URIRef("http://example.org/someIRI")) in output_graph
+    # Unknown label: literal remains unchanged
+    assert (EX.subj3, EX.hasCategory, Literal("unknownlabel")) in output_graph
 
-    # --- Check log entries ---
+    # Non-literals remain untouched
+    assert (EX.subj4, EX.hasValue, URIRef("http://example.org/someIRI")) in output_graph
+
+    # --- 2. Check log entries ---
     log = transformer.log.entries
-    geology_log = next(e for e in log if e["original"] == "Geology")
+
+    # Exact match log
+    geology_log = next(e for e in log if e["original"] == "geology")
     assert geology_log["replacement"] == "http://example.org/ontology#Geology"
-    assert geology_log["reason"] == "unambiguous match"
+    assert geology_log["reason"] == "exact match"
+
+    # Fuzzy match log
+    biolgy_log = next(e for e in log if e["original"] == "biolgy")
+    assert biolgy_log["replacement"] == "http://example.org/ontology#Biology"
+    assert "fuzzy match" in biolgy_log["reason"]
 
-    unknown_log = next(e for e in log if e["original"] == "UnknownLabel")
+    # Unknown label log
+    unknown_log = next(e for e in log if e["original"] == "unknownlabel")
     assert unknown_log["replacement"] is None
-    assert unknown_log["reason"] == "no match in label map"
+    assert unknown_log["reason"] == "no match found"