Test MERGE direction in Neo4j

run_test.py

from neo4j import GraphDatabase

class TestDirection:

    def __init__(self, uri, user, password):
        self.driver = GraphDatabase.driver(uri, auth=(user, password))

    def close(self):
        self.driver.close()

    def run_test(self):
        left_count = 0
        right_count = 0
        with self.driver.session() as session:
            for i in range(10000):
                create = session.write_transaction(self._createNode)
                right = session.write_transaction(self._matchRight)
                if right is True:
                    right_count = right_count + 1
                left = session.write_transaction(self._matchLeft)
                if left is True:
                    left_count = left_count + 1
                cleanup = session.write_transaction(self._cleanup)
        print("Left: " + str(left_count))
        print("Right: " + str(right_count))

    @staticmethod
    def _createNode(tx):
        result = tx.run("MERGE ({side: 'left'})-[:edge]-({side:'right'})")
        if result.single() is None:
            return False
        return True

    @staticmethod
    def _matchRight(tx):
        result = tx.run("MATCH (l{side: 'left'})-[:edge]->(r{side:'right'}) RETURN l, r")
        if result.single() is None:
            return False
        return True

    @staticmethod
    def _matchLeft(tx):
        result = tx.run("MATCH (l{side: 'left'})<-[:edge]-(r{side:'right'}) RETURN l, r")
        if result.single() is None:
            return False
        return True

    @staticmethod
    def _cleanup(tx):
        result = tx.run("MATCH (n) DETACH DELETE n")
        if result.single() is None:
            return False
        return True


if __name__ == "__main__":
    tester = TestDirection("bolt://localhost:7687", "neo4j", "test")
    tester.run_test()
    tester.close()