NameError: global name 'client' is not defined

Question

Here i did the python class for connecting mongo and get the data from mongo database and process it i did the unit test cases for this i got following error

NameError: global name 'client' is not defined

python class :

 from pymongo.errors import ConnectionFailure, AutoReconnect
 import pymongo
 from pymongo import MongoClient

 class ConnectionError(Exception):
   pass



class ChkMongo:

item_list=[]
dict1={}

def makeMongocon(self):

    global client
    try :
        client = MongoClient("localhost", 27017)

    except AutoReconnect, e:
        raise ConnectionFailure(str(e))

def findRecords(self):
    self.db = client.serv
    for item in self.db.serv.find():
        self.item_list.insert(0,item)
    return self.item_list





if __name__ == '__main__':
  c=ChkMongo()
  c.makeMongocon()
  print(c.findRecords())

my unit test case

from pymongo.errors import ConnectionFailure
 import unittest;
 from app.ChkMongo import *  

class TestChkMongo(unittest.TestCase):

def setUp(self):
    self.c=ChkMongo()

def test_makeMongocon(self):
    self.assertRaises(ConnectionFailure,self.c.makeMongocon)
def test_findRecords(self):
    print(self.c.findRecords())
    self.assertDictContainsSubset({'name':'matthew'},self.c.findRecords())
def test_calculate_charge_with_tax(self):
    self.assertAlmostEqual(290,self.c.calculate_charge_with_tax('matthew'))


if __name__ == '__main__':
  unittest.main()

i got following error when run the test cases but run the python script that will work fine

Error:

Traceback (most recent call last):
  File "/test/test_chkMongo.py", line 16, in test_findRecords
    print(self.c.findRecords())
  File "n/app/ChkMongo.py", line 29, in findRecords
    self.db = client.serventer code here
NameError: global name 'client' is not defined

Answer 1

For me it happens when running my test with Python 3.6.x and Python 2.x. Some exception names are not available in Python 2.x.

For example with ConnectionError:

in Python 2.x, using python interpreter, I get a NameError because it does not recognize it.

>>> raise ConnectionError
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'ConnectionError' is not defined

in Python 3.6.x, using python3 interpreter, I get the right ConnectionError

>>> raise ConnectionError
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ConnectionError

It can be tricky when working with multiple versions of Python or different venv. Hope it helps with the debugging.