Source code for langchain_community.graphs.kuzu_graph

from typing import Any, Dict, List

[docs]class KuzuGraph: """Kùzu wrapper for graph operations. *Security note*: Make sure that the database connection uses credentials that are narrowly-scoped to only include necessary permissions. Failure to do so may result in data corruption or loss, since the calling code may attempt commands that would result in deletion, mutation of data if appropriately prompted or reading sensitive data if such data is present in the database. The best way to guard against such negative outcomes is to (as appropriate) limit the permissions granted to the credentials used with this tool. See for more information. """
[docs] def __init__(self, db: Any, database: str = "kuzu") -> None: try: import kuzu except ImportError: raise ImportError( "Could not import Kùzu python package." "Please install Kùzu with `pip install kuzu`." ) self.db = db self.conn = kuzu.Connection(self.db) self.database = database self.refresh_schema()
@property def get_schema(self) -> str: """Returns the schema of the Kùzu database""" return self.schema
[docs] def query(self, query: str, params: dict = {}) -> List[Dict[str, Any]]: """Query Kùzu database""" result = self.conn.execute(query, params) column_names = result.get_column_names() return_list = [] while result.has_next(): row = result.get_next() return_list.append(dict(zip(column_names, row))) return return_list
[docs] def refresh_schema(self) -> None: """Refreshes the Kùzu graph schema information""" node_properties = [] node_table_names = self.conn._get_node_table_names() for table_name in node_table_names: current_table_schema = {"properties": [], "label": table_name} properties = self.conn._get_node_property_names(table_name) for property_name in properties: property_type = properties[property_name]["type"] list_type_flag = "" if properties[property_name]["dimension"] > 0: if "shape" in properties[property_name]: for s in properties[property_name]["shape"]: list_type_flag += "[%s]" % s else: for i in range(properties[property_name]["dimension"]): list_type_flag += "[]" property_type += list_type_flag current_table_schema["properties"].append( (property_name, property_type) ) node_properties.append(current_table_schema) relationships = [] rel_tables = self.conn._get_rel_table_names() for table in rel_tables: relationships.append( "(:%s)-[:%s]->(:%s)" % (table["src"], table["name"], table["dst"]) ) rel_properties = [] for table in rel_tables: table_name = table["name"] current_table_schema = {"properties": [], "label": table_name} query_result = self.conn.execute( f"CALL table_info('{table_name}') RETURN *;" ) while query_result.has_next(): row = query_result.get_next() prop_name = row[1] prop_type = row[2] current_table_schema["properties"].append((prop_name, prop_type)) rel_properties.append(current_table_schema) self.schema = ( f"Node properties: {node_properties}\n" f"Relationships properties: {rel_properties}\n" f"Relationships: {relationships}\n" )