python mocking open method using mox

Question

When I try to mock open method, I am facing issue. Please find the sample code :

import glob
import re
#from __builtin__ import open

class DiskManager:
def __init__(self):
  print("Called init method")
def __get_xyz_from_serial(self, serial):

for host in glob.glob("dir/*/host"):
  for target in glob.glob(host + "/target*/*/filename"):
    try:

      with open(target) as f:
        serial_num = f.read().strip()
    except:
      print("Failed to read : %s " % target)
      continue

    serial_num  = (unicode(("".join(i for i in serial_num if (32 < ord(i) < 127 )))
                      .encode("utf8")))

    if(serial == serial_num):
      host_num = re.split(r"(\d+)", host)[1]
      return host_num
print("No host detected")
return None

Test Method :

# - *- coding: utf- 8 - *-i
from mox import Mox, IgnoreArg, Func, Comparator, StrContains
from mock import patch, Mock, mock_open
import unittest
#import disk_manager as disk_mgr
from disk_manager import  DiskManager
import __builtin__
import glob
import StringIO

class DiskManagerTest(unittest.TestCase):
  def setUp(self):
    self.mox = Mox()

  def tearDown(self):
    self.mox.UnsetStubs()
    self.mox.ResetAll()


  def test_hba_serial_using_mox(self):
    my_text = "¥C010"
    disk_mgr = DiskManager()
    #self.mox.StubOutClassWithMocks(disk_mgr,"DiskManager")
    #self.mox.StubOutWithMock(disk_mgr, "_DiskManager__get_xyz_from_serial")
    self.mox.StubOutWithMock(glob,"glob")
    directory_list = ['dir1','dir2']
    glob.glob("dir/*/host").AndReturn(directory_list)
    file_list  = ['file3','file2']
    #glob.glob(directory_list[0]+ "/target*/*/filename").AndReturn('file1')  
    #glob.glob(directory_list[1]+ "/target*/*/filename").AndReturn('file2')  
    file3 = glob.glob(directory_list[0]+ "/target*/*/filename").AndReturn(file_list)
    file4 = glob.glob(directory_list[1]+ "/target*/*/filename").AndReturn(file_list)
    print(file3)

    my_text = "AAAAAA"


    self.mox.ReplayAll()

    self.assertEqual(disk_mgr._DiskManager__get_xyz_from_serial("AAAAAA"), 'file3')

    self.mox.VerifyAll()

For mocking open method I tried :

self.mox.StubOutWithMock(__builtin__, 'open')

But this does not solved the issue. I am getting this error :

  File "/usr/lib64/python2.7/linecache.py", line 127, in updatecache
with open(fullname, 'rU') as fp:

Can someone guide me the correct process to mock file opening. I have tried these combinations :

    self.mox.StubOutWithMock(__builtin__, 'open')
    #self.mox.StubOutWithMock(fl, "close")

   # f1 = self.mox.CreateMockAnything(file)
   # self.mox.StubOutWithMock(fl, "read")
    #__builtin__.__call__(IgnoreArg()).AndReturn(f1)
    #open(file_path).AndReturn("")
    #__builtin__.open('file3', 'r').AndReturn(f1)
   # f1.read().AndReturn("C010")
    #op.open('file1', 'a').AndReturn(f1)
   # fl.__enter__().AndReturn("010")
   # f1.read().AndReturn("C010")
   # fl.__exit__(IgnoreArg(), IgnoreArg(), IgnoreArg())
   # f1.close()
    #open('file1', 'r').AndReturn(StringIO("fake file content")) 
    #open('file2', 'r').AndReturn(StringIO("fake file content")) 
    #open('file3', 'r').AndReturn(StringIO("C010"))

Any insight / solution will be appreciated.

python mocking open method using mox

0 Answers0