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raise AttributeError(name) AttributeError: LCC_GetChannelHandle

I am very new in python cffi. I have to access my temprature module by using its Index or with its channel name. I am trying with both as you can see in my QmixTC class. I am getting attribute error. In other class, there is no errors. Can someone help me understand where is the problem. I am putting my code as well as error trace. Thanks.
main code with name qmix.py (importing it in to sample code):
class QmixTC (object):
"""
"""
def __init__(self, index=0, handle=None,name=''):
self.dll_dir = DLL_DIR
self.dll_file = os.path.join(self.dll_dir,
'labbCAN_Controller_API.dll')
self._ffi = FFI()
self._ffi.cdef(CONTROLLER_HEADER)
self._dll = self._ffi.dlopen(self.dll_file)
self._handle = self._ffi.new('dev_hdl *', 0)
if handle is None:
self.index = index
self._handle = self._ffi.new('dev_hdl *', 0)
self._call('LCC_GetChannelHandle', self.index, self._handle)
else:
self.index = None
self._handle = handle
self._ch_name="QmixTC_1_DO0_INA"
self._channel = self._ch_name + str(index)
self._call('LCC_LookupChanByName',
bytes(self._channel,'utf8'),
self._handle)
self.name = name
def _call(self, func_name, *args):
func = getattr(self._dll, func_name)
r = func(*args)
r = CHK(r, func_name, *args)
return r
def Setpoint_write (self, setpoint):
"""
Write setpoint value to controller device.
Parameters
[in] ChanHdl Valid handle of open controller channel
[in] fSetPointValue The setpoint value to write
Returns
Error code - ERR_NOERR indicates success
"""
self._call('LCC_WriteSetPoint', self._handle[0], setpoint)
def enable_controllLoop (self, enable):
"""
Enables / disables a control loop.
If the control loop is enabled, then the output value is calculated periodically.
Parameters
ChanHdl Valid handle of a controller channel
Enable 1 = enable, 0 = disable
Returns
Error code - ERR_NOERR indicates success
"""
self._call('LCC_EnableControlLoop', self._handle[0], enable)
def read_temp_value (self, actualvalue):
"""
Read actual value from device.
Parameters
[in] ChanHdl Valid handle of open controller channel
[out] pfActualValue Returns the actual controller value
Returns
Error code - ERR_NOERR indicates success
"""
self._call('LCC_ReadActualValue', self._handle[0], actualvalue)
if __name__ == '__main__':
import os.path as op
dll_dir = op.normpath('C:\\Users\\Ravikumar\\AppData\\Local\\QmixSDK')
config_dir = op.normpath('C:\\Users\\Public\\Documents\\QmixElements\\Projects\\QmixTC_Pump\\Configurations\\QmixTC_pump')
bus = QmixBus(config_dir=config_dir)
bus.open()
bus.start()
controller_0 = QmixTC(index=0)
controller_0.enable_controllLoop(1)
sample program:
from __future__ import division, print_function
from win32api import GetSystemMetrics
import numpy as np
import os
import qmix
import pandas as pd
#%% CHANNEL INITIALIZATION
if __name__ == '__main__':
dll_dir = ('C:\\Users\\Ravikumar\\AppData\\Local\\QmixSDK')
config_dir = ('C:\\Users\\Public\\Documents\\QmixElements\\Projects\\QmixTC_test1\\Configurations\\QmixTC_test1')
qmix_bus = qmix.QmixBus(config_dir=config_dir,dll_dir=dll_dir)
qmix_bus.open()
qmix_bus.start()
controller_0 = qmix.QmixTC(index=0)
controller_0.Setpoint_write(50)
error:
Traceback (most recent call last):
File "<ipython-input-5-40d4a3db9493>", line 17, in <module>
controller_0 = qmix.QmixTC(index=0)
File "qmix.py", line 921, in __init__
self._call('LCC_GetChannelHandle', self.index, self._handle)
File "qmix.py", line 937, in _call
func = getattr(self._dll, func_name)
File "C:\Users\Ravikumar\Anaconda2\lib\site-packages\cffi\api.py", line 875, in __getattr__
make_accessor(name)
File "C:\Users\Ravikumar\Anaconda2\lib\site-packages\cffi\api.py", line 870, in make_accessor
raise AttributeError(name)
AttributeError: LCC_GetChannelHandle

How do I mock an open(...).write() without getting a 'No such file or directory' error?

I've based my solution on:
How do I mock an open used in a with statement (using the Mock framework in Python)?,
AttributeError: <module '__main__' from [..] does not have the attribute 'open',
http://www.voidspace.org.uk/python/mock/helpers.html#mock.mock_open
I have a class, which I can instantiate, which writes to a file. I'm trying to test it, but I'm having problems mocking open(). I'm using the following as the smallest piece of code, which can
import os
import unittest
from unittest.mock import mock_open, patch
__author__ = 'drews'
class MockPathExists(object):
def __init__(self, return_value):
self.received_args = None
self.return_value = return_value
def __call__(self, *args, **kwargs):
self.received_args = args
return self.return_value
class WriteData:
def __init__(self, dir, name='World'):
self.name = name
self.dir = dir
def dump(self):
if os.path.exists(self.dir):
with open('{0}/output.text'.format(self.dir), 'w+') as fp:
fp.write('Hello, {0}!'.format(self.name))
class TestListWindowsPasswords(unittest.TestCase):
def setUp(self):
self._orig_pathexists = os.path.exists
os.path.exists = MockPathExists(True)
def test_dump(self):
m = mock_open()
with patch.object(WriteData, 'open', m, create=True):
data_writer = WriteData(
dir='/my/path/not/exists',
name='Foo'
)
data_writer.dump()
self.assertEqual(os.path.exists.received_args[0], '/my/path/not/exists/output.text')
m.assert_called_once_with('/my/path/not/exists/output.text', 'w+')
handle = m()
handle.write.assert_called_once_with('Hello, Foo!')
def tearDown(self):
os.path.exists = self._orig_pathexists
When I run this, I get the following error:
Error
Traceback (most recent call last):
File "/Users/drews/Development/tool/tests/test_mockopen.py", line 41, in test_dump
data_writer.dump()
File "/Users/drews/Development/tool/tests/test_mockopen.py", line 25, in dump
with open('{0}/output.text'.format(self.dir), 'w+') as fp:
FileNotFoundError: [Errno 2] No such file or directory: '/my/path/not/exists/output.text'
How can I mock open(), so that it just returns a file_pointer, and doesn't try to interact with the file system at all?

Mock builtins.open (or module.open, module = the module name that contains WriteData) with the mock_open:
import builtins
class TestListWindowsPasswords(unittest.TestCase):
def setUp(self):
self._orig_pathexists = os.path.exists
os.path.exists = MockPathExists(True)
def test_dump(self):
with patch('builtins.open', unittest.mock.mock_open()) as m:
data_writer = WriteData(
dir='/my/path/not/exists',
name='Foo'
)
data_writer.dump()
self.assertEqual(os.path.exists.received_args[0], '/my/path/not/exists') # fixed
m.assert_called_once_with('/my/path/not/exists/output.text', 'w+')
handle = m()
handle.write.assert_called_once_with('Hello, Foo!')

You can use the __enter__ magic method to simulate which:
from unittest.mock import patch, MagicMock, call, mock_open
#patch('os')
#patch('builtins.open', new_callable=mock_open())
def test_dump(self, mock_open_file, mock_os):
data_writer = WriteData(dir='/my/path/not/exists', name='Foo')
mock_os.path.exists.assert_called_once_with('/my/path/not/exists')
mock_open_file.assert_called_once_with('/my/path/not/exists/output.text', 'w+')
mock_open_file.return_value.__enter__().write.assert_called_once_with('Hello, Foo!')
Hope this helps!

how to return a collection from mongodb using pymongo

I'm trying to create a Collection Class in Python to access the various collections in my db. Here's what I've got:
import sys
import os
import pymongo
from pymongo import MongoClient
class Collection():
client = MongoClient()
def __init__(self, db, collection_name):
self.db = db
self.collection_name = collection_name
# self.data_base = getattr(self.client, db)
# self.collObject = getattr(self.data_base, self.collection_name)
def getCollection(self):
data_base = getattr(self.client, self.db)
collObject = getattr(data_base, self.collection_name)
return collObject
def getCollectionKeys(self, collection):
"""Get a set of keys from a collection"""
keys_list = []
collection_list = collection.find()
for document in collection_list:
for field in document.keys():
keys_list.append(field)
keys_set = set(keys_list)
return keys_set
if __name__ == '__main__':
print"Begin Main"
agents = Collection('hkpr_restore','agents')
print "agents is" , agents
agents_collection = agents.getCollection
print agents_collection
print agents.getCollectionKeys(agents_collection)
I get the following output:
Begin Main
agents is <__main__.Collection instance at 0x10ff33e60>
<bound method Collection.getCollection of <__main__.Collection instance at 0x10ff33e60>>
Traceback (most recent call last):
File "collection.py", line 52, in <module>
print agents.getCollectionKeys(agents_collection)
File "collection.py", line 35, in getCollectionKeys
collection_list = collection.find()
AttributeError: 'function' object has no attribute 'find'
The function getCollectionKeys works fine outside of a class. What am I doing wrong?

This line:
agents_collection = agents.getCollection
Should be:
agents_collection = agents.getCollection()
Also, you don't need to use getattr the way you are. Your getCollection method can be:
def getCollection(self):
return self.client[self.db][self.collection_name]

Django import settings error

I have the following script for scraping a webform:
#!/usr/bin/env python
"""
Python script for searching firms on http://www.adviserinfo.sec.gov/IAPD/Content/Search/iapd_Search.aspx
Assumes that the input Excel file is in the same directory as this script.
"""
import os
import re
import sys
import django
import mechanize
from bs4 import BeautifulSoup
from xlrd import open_workbook
XLSX_FILE = 'Legal Names.xlsx'
IAPD_URL = 'http://www.adviserinfo.sec.gov/IAPD/Content/Search/iapd_Search.aspx'
#------------------------------------------------------------------------------------------
sys.path.append(os.path.realpath(os.path.join(os.path.dirname(__file__), 'scraper/')))
sys.path.append(os.path.realpath(os.path.join(os.path.dirname(__file__), 'scraper/scraper/')))
os.environ['DJANGO_SETTINGS_MODULE'] = 'settings'
django.setup()
from django.core.exceptions import ObjectDoesNotExist
from custom_scraper.models import *
#------------------------------------------------------------------------------------------
def legal_names(file=XLSX_FILE):
'''
Read in legal names from the excel spreadsheet with the assumption
that names to be searched for are in column 1. Skip row 1 header
'''
wb = open_workbook(file)
s = wb.sheets()[0]
col = 1
for row in range(s.nrows)[1:]:
name = s.cell(row, col).value
if type(name) == int:
continue
yield name
class IapdScraper(object):
def __init__(self):
self.br = mechanize.Browser()
self.br.addheaders = [('User-agent',
'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.63 Safari/535.7')]
def scrape(self, q):
'''
Search for a Firm in the IAPD database by name
'''
def select_form(form):
return form.attrs.get('id', None) == 'aspnetForm'
try:
firm = IapdFirm.objects.get(query_name=q)
except ObjectDoesNotExist:
firm = IapdFirm(query_name=q)
firm.save()
else:
if firm.checked:
return
self.br.open(IAPD_URL)
self.br.select_form(predicate=select_form)
self.br.form['ctl00$cphMainContent$ucUnifiedSearch$rdoSearchBy'] = ['rdoOrg']
self.br.submit()
self.br.select_form(predicate=select_form)
self.br.form['ctl00$cphMainContent$ucUnifiedSearch$txtFirm'] = q.encode('utf8')
self.br.submit()
s = BeautifulSoup(self.br.response().read())
r = re.compile(r'^ctl\d+_cphMainContent_grOrgResults$')
t = s.find('table', id=r)
if not t: # Not found
print 'Not Found'
firm.checked = True
firm.save()
return
tr = t.findAll('tr', recursive=False)
tr = tr[2:-1] # Skip records-per-page header/footer and title header
for row in tr:
td = row.findAll('td', recursive=False)
firm.legal_name = td[0].b.text.strip()
firm.other_name = td[1].text.strip()
firm.sec_number = td[2].text.strip()
firm.address = td[3].text.strip()
firm.checked = True
firm.save()
if __name__ == '__main__':
scraper = IapdScraper()
for name in legal_names():
print '\nq=%s' % name
scraper.scrape(q=name)
When I run the script in my venv, however, I get the following error:
c:\Users\bal2155\venv\Scripts>scraper.py
Traceback (most recent call last):
File "C:\Users\bal2155\venv\Scripts\scraper.py", line 26, in <module>
django.setup()
File "C:\Python27\lib\site-packages\django\__init__.py", line 20, in setup
configure_logging(settings.LOGGING_CONFIG, settings.LOGGING)
File "C:\Python27\lib\site-packages\django\conf\__init__.py", line 46, in __ge
tattr__
self._setup(name)
File "C:\Python27\lib\site-packages\django\conf\__init__.py", line 42, in _set
up
self._wrapped = Settings(settings_module)
File "C:\Python27\lib\site-packages\django\conf\__init__.py", line 98, in __in
it__
% (self.SETTINGS_MODULE, e)
ImportError: Could not import settings 'settings' (Is it on sys.path? Is there a
n import error in the settings file?): No module named settings
I have a inkling that this has to do either with how I've set up the venv or how I downloaded django. I've checked the documentation for the latter and I'm not sure what the myproject.settings extension means. Any help here would be greatly appreciated.

Python Invalid Snytax

Below is the code I have been working on.
The very last line write_csv('twitter_gmail.csv', messages, append=True) throws a
[ec2-user#ip-172-31-46-164 ~]$ ./twitter_test16.sh
Traceback (most recent call last):
File "./twitter_test16.sh", line 53, in
write_csv('twitter_gmail.csv', messages, append=True)
NameError: name 'messages' is not defined
I have messages defined so I dont understand why it would do that.
import csv
import json
import oauth2 as oauth
import urllib
import sys
import requests
import time
CONSUMER_KEY = "
CONSUMER_SECRET = "
ACCESS_KEY = "
ACCESS_SECRET = "
class TwitterSearch:
def __init__(self, ckey=CONSUMER_KEY, csecret=CONSUMER_SECRET,
akey=ACCESS_KEY, asecret=ACCESS_SECRET,
query='https://api.twitter.com/1.1/search/tweets.{mode}?{query}'
):
consumer = oauth.Consumer(key=ckey, secret=csecret)
access_token = oauth.Token(key=akey, secret=asecret)
self.client = oauth.Client(consumer, access_token)
self.query = query
def search(self, q, mode='json', **queryargs):
queryargs['q'] = q
query = urllib.urlencode(queryargs)
return self.client.request(self.query.format(query=query, mode=mode))
def write_csv(fname, rows, header=None, append=False, **kwargs):
filemode = 'ab' if append else 'wb'
with open(fname, filemode) as outf:
out_csv = csv.writer(outf, **kwargs)
if header:
out_csv.writerow(header)
out_csv.writerows(rows)
def main():
ts = TwitterSearch()
response, data = ts.search('#gmail.com', result_type='recent')
js = json.loads(data)
messages = ([msg['created_at'], msg['txt'], msg['user']['id']] \
for msg in js.get('statuses', []))
write_csv('twitter_gmail.csv', messages, append=True)

The previous line is missing a parenthesis.
messages = ([msg['created_at'], msg['txt'], msg['user']['id']] for msg in js.get('statuses', [])
Should be:
messages = ([msg['created_at'], msg['txt'], msg['user']['id']] for msg in js.get('statuses', []))
I'm surprised that it works when you change to print? Are you also changing the comprehension when you do that?
You asked why the line number of the error was after the bad syntax?
Try putting this in line one of a file and running it, and note the line of the SyntaxError.
a = (]
Then try this and check out the line number:
a = (
b = "some stuff"
Finally, try this:
a = (
b = "some stuff"
Think about when you would know that the programmer had made a python-illegal typo if you were reading the code and carrying it out via pen and paper.
Basically, a SyntaxError is raised as soon as it can be unambiguously determined that invalid syntax was used, which is often immediately after a statement where a mistake was made, not immediately at.
You'll frequently get line numbers on SyntaxErrors that are a line (or several lines if there's empty lines or a corner case) below the actual typo.