Blank node replace fix (#71)

Author: usebeforefree

dkg/utils/knowledge_collection_tools.py

@@ -6,6 +6,7 @@
 from pyld import jsonld
 from dkg.constants import DEFAULT_RDF_FORMAT, DEFAULT_CANON_ALGORITHM, ESCAPE_MAP
 from rdflib import Graph, BNode, URIRef, Literal as RDFLiteral
+from rdflib.exceptions import ParserError as RDFParserError
 from uuid import uuid4
 from web3 import Web3
 import math
@@ -154,29 +155,26 @@ def replace_blank_node(term):
 
         return term  # Return IRIs or Literals unchanged
 
-    # Create a temporary graph for parsing individual quads
-    result = []
-
-    # Process each N-Quad string individually to maintain order
-    for nquad in nquads_list:
-        if not nquad.strip():
-            continue
+    all_nquads = "\n".join(nquad for nquad in nquads_list if nquad.strip())
 
-        # Parse single N-Quad
-        g = Graph()
-        g.parse(data=nquad, format="nquads")
+    # Create a single Dataset
+    g = Graph()
+    try:
+        g.parse(data=all_nquads, format="nt")
+    except RDFParserError:
+        raise UnsupportedJSONLD(nquads_list)
 
-        # Get the triple and replace blank nodes
-        for s, p, o in g:
-            updated_quad = (
-                replace_blank_node(s),
-                replace_blank_node(p),
-                replace_blank_node(o),
-            )
-            # Format as N-Quad string
-            result.append(
-                f"{updated_quad[0].n3()} {updated_quad[1].n3()} {updated_quad[2].n3()} ."
-            )
+    # Process all quads
+    result = []
+    for s, p, o in g:
+        updated_quad = (
+            replace_blank_node(s),
+            replace_blank_node(p),
+            replace_blank_node(o),
+        )
+        result.append(
+            f"{updated_quad[0].n3()} {updated_quad[1].n3()} {updated_quad[2].n3()} ."
+        )
 
     return result
 
@@ -266,3 +264,44 @@ def escape_literal_dict(obj):
         return escape_literal_string(s=obj)
     else:
         return obj
+
+
+# Used when JSON-LD parsing fails due to quads being passed instead of triples
+class UnsupportedJSONLD(Exception):
+    def __init__(self, nquads_list):
+        self.nquads_list = nquads_list
+        self.message = f"""
+Unsupported JSON-LD input detected
+
+After parsing the JSON-LD input, the parser detected creation of new named graphs.
+The DKG does not support custom named graphs.
+
+Problematic Quads:
+
+{self.find_problematic_quads()}
+
+Full Parsed N-Quads Array:
+
+{self.format_nquads_list()}
+
+"""
+        super().__init__(self.message)
+
+    def __str__(self):
+        return f"{self.__class__.__name__}: {self.message}"
+
+    def format_nquads_list(self):
+        return "\n".join(nquad.strip() for nquad in self.nquads_list)
+
+    def find_problematic_quads(self):
+        problematic = []
+        g = Graph()
+        for quad in self.nquads_list:
+            if not quad.strip():
+                continue
+            try:
+                g.parse(data=quad, format="nt")
+            except RDFParserError:
+                problematic.append(quad)
+
+        return "\n".join(f"{i + 1}. {quad}" for i, quad in enumerate(problematic))