diff --git a/cognee/infrastructure/databases/graph/neo4j_driver/adapter.py b/cognee/infrastructure/databases/graph/neo4j_driver/adapter.py
index b23bf8e00..50cc88605 100644
--- a/cognee/infrastructure/databases/graph/neo4j_driver/adapter.py
+++ b/cognee/infrastructure/databases/graph/neo4j_driver/adapter.py
@@ -410,6 +410,38 @@ class Neo4jAdapter(GraphDBInterface):
return await self.query(query, params)
+ def _flatten_edge_properties(self, properties: Dict[str, Any]) -> Dict[str, Any]:
+ """
+ Flatten edge properties to handle nested dictionaries like weights.
+
+ Neo4j doesn't support nested dictionaries as property values, so we need to
+ flatten the 'weights' dictionary into individual properties with prefixes.
+
+ Args:
+ properties: Dictionary of edge properties that may contain nested dicts
+
+ Returns:
+ Flattened properties dictionary suitable for Neo4j storage
+ """
+ flattened = {}
+
+ for key, value in properties.items():
+ if key == "weights" and isinstance(value, dict):
+ # Flatten weights dictionary into individual properties
+ for weight_name, weight_value in value.items():
+ flattened[f"weight_{weight_name}"] = weight_value
+ elif isinstance(value, dict):
+ # For other nested dictionaries, serialize as JSON string
+ flattened[f"{key}_json"] = json.dumps(value, cls=JSONEncoder)
+ elif isinstance(value, list):
+ # For lists, serialize as JSON string
+ flattened[f"{key}_json"] = json.dumps(value, cls=JSONEncoder)
+ else:
+ # Keep primitive types as-is
+ flattened[key] = value
+
+ return flattened
+
@record_graph_changes
@override_distributed(queued_add_edges)
async def add_edges(self, edges: list[tuple[str, str, str, dict[str, Any]]]) -> None:
@@ -448,11 +480,13 @@ class Neo4jAdapter(GraphDBInterface):
"from_node": str(edge[0]),
"to_node": str(edge[1]),
"relationship_name": edge[2],
- "properties": {
- **(edge[3] if edge[3] else {}),
- "source_node_id": str(edge[0]),
- "target_node_id": str(edge[1]),
- },
+ "properties": self._flatten_edge_properties(
+ {
+ **(edge[3] if edge[3] else {}),
+ "source_node_id": str(edge[0]),
+ "target_node_id": str(edge[1]),
+ }
+ ),
}
for edge in edges
]
diff --git a/examples/python/weighted_graph_visualization.html b/examples/python/weighted_graph_visualization.html
index 2e7f67e31..89920a780 100644
--- a/examples/python/weighted_graph_visualization.html
+++ b/examples/python/weighted_graph_visualization.html
@@ -37,8 +37,8 @@