Python unittest mocking influxdb

I want to test a class which passes data to an influx-database.
For that purpose I use influxdb.InfluxDBClient. For the unit-tests I want to mock influxdb.InfluxDBClient, but it seems that this is not working. I always get timeouts, so the mocking does not work at all.

This is the class I want to test:

''' Client for influxDB1. '''
from influxdb import InfluxDBClient

class Influx1Writer:
''' Client to access influxDB1. '''
        
    def __init__(self, host, port, user, password, dbname, usessl) -> None:
    ''' Initializer, will be called from constructor. '''
        self.client = InfluxDBClient(
            host=host,
            port=port,
            username=user,
            password=password,
            database=dbname,
            ssl=usessl)
        self.client.create_database(dbname)
        self.client.switch_database(dbname)
        self.client.switch_user(user, password)

This is the test case

''' Unittest writer for influxdb, version 1. '''
import unittest
from unittest.mock import patch, MagicMock

from influxdb import InfluxDBClient
from influx.influx_writer_1 import Influx1Writer

class TestInflux1Writer(unittest.TestCase):
    ''' Unittests of Influx1Writer. '''

    host = "host"
    port = 8080
    user = "user"
    password = "password"
    dbname = "dbname"
    usessl = False

    def setUp(self) -> None:
        ''' Setup test fixture. '''
        mock_influx = MagicMock('influxdb.InfluxDBClient')
        self.handler = Influx1Writer(self.host, \
                                     self.port, \
                                     self.user, \
                                     self.password, \
                                     self.dbname, \
                                     self.usessl)
        mock_influx.assert_called_with(self.host, \
                                        self.port, \
                                        self.user, \
                                        self.password, \
                                        self.dbname, \
                                        self.usessl)

        super().setUp()

    def tearDown(self) -> None:
        ''' Tear down test fixture. '''
        self.handler = None
        super().tearDown()

    ###

    @patch('influxdb.InfluxDBClient')
    @patch('influxdb.InfluxDBClient.create_database')
    @patch('influxdb.InfluxDBClient.switch_database')
    @patch('influxdb.InfluxDBClient.switch_user')
    def test_01a_init_called(self, mock_client, mock_create_database, mock_switch_database, mock_switch_user) -> None:
        ''' Check InfluxDBClient is called with parameters. '''
        mock_client.__init__.assert_called_with(self.host, self.port, self.user, self.password, self.dbname, self.usessl)
        mock_create_database.assert_called_with(self.dbname)
        mock_switch_database.assert_called_with(self.dbname)
        mock_switch_user.assert_called_with(self.dbname)
        self.assertEqual(type(self.handler), Influx1Writer)

When the test is executed, a timeout will occur. This means that influxdb.InfluxDBClient is not mocked.

What am I doing wrong here?

Found the solution, thank you @blhsing

    def setUp(self) -> None:
        ''' Setup test fixture. '''
        self.patch_client = patch('influx.influx_writer_1.InfluxDBClient')
        mock_influx = self.patch_client.start()
        self.client = Influx1Writer(self.host, \
                                    self.port, \
                                    self.user, \
                                    self.password, \
                                    self.dbname, \
                                    self.usessl)
        mock_influx.assert_called_with( host=self.host, \
                                        port=self.port, \
                                        username=self.user, \
                                        password=self.password, \
                                        database=self.dbname, \
                                        ssl=self.usessl)
        super().setUp()

By the time you patch influxdb.InfluxDBClient, it is already imported into the namespace of the module influx.influx_writer_1 so the module keeps a reference to the original InfluxDBClient even after influxdb.InfluxDBClient is patched. Instead, you should patch influx.influx_writer_1.InfluxDBClient so the name InfluxDBClient within the module influxdb.InfluxDBClient can actually be reassigned.

Also, you should use patch instead of MagicMock to patch an object. To patch an object for the tests in a TestCase, call the start method of the patcher in the setUp method, and then restore the original object by calling the stop method of the patcher in the tearDown method of the TestCase:

def setUp(self) -> None:
''' Setup test fixture. '''
self.patcher = patch('influx.influx_writer_1.InfluxDBClient')
self.patcher.start()
self.handler = Influx1Writer(self.host, \
self.port, \
self.user, \
self.password, \
self.dbname, \
self.usessl)
Influx1Writer.assert_called_with(self.host, \
self.port, \
self.user, \
self.password, \
self.dbname, \
self.usessl)
super().setUp()
def tearDown(self) -> None:
''' Tear down test fixture. '''
self.patcher.stop()
self.handler = None
super().tearDown()