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Python Suds.Client Should it Close or Not

I am using the suds package to make API request from one website. I wrote a function which opens up the client to the website and make request.
I am wondering should I or how can I terminate the connection in the end of the function?
I am wondering will the client be something like the MySQLDb.connect that actually opens up many many separate API connections that never close every time I call this function.
from suds.client import Client
import sys, re
def querysearch(reqPartNumber, reqMfg, lock):
try:
client = Client('http://app....')
userInfo = {'id':.., 'password':...}
apiResponse = client.service.getParts(...)
...
print apiResponse
except:
...

SOAP is still an HTTP request, which is stateless. Each request will start a whole new connection, re-auth, etc. Browsers kind of short circuit that with cookies, but SOAP doesn't. So, you don't need to close the connection, it's already closed by the time suds returns your data back to you.
Additionally, looking at the latest source, Client() doesn't define a close or __exit__ method, so there's nothing you really have to do here.

Cleanly Mocking Remote Servers and APIs for Django Unittests

I have a thorny problem that I can't seem to get to grips with. I am
currently writing unit tests for a django custom auth-backend. On our
system we actually have two backends: one the built-in django backend
and the custom backend that sends out requests to a Java based API
that returns user info in the form of XML. Now, I am writing unit
tests so I don't want to be sending requests outside the system like
that, I'm not trying to test the Java API, so my question is how can I
get around this and mock the side-effects in the most robust way.
The function I am testing is something like this, where the url
settings value is just the base url for the Java server that
authenticates the username and password data and returns the xml, and the service value is
just some magic for building the url query, its unimportant for
us:
#staticmethod
def get_info_from_api_with_un_pw(username, password, service=12345):
url = settings.AUTHENTICATE_URL_VIA_PASSWORD
if AUTH_FIELD == "username":
params = {"nick": username, "password": password}
elif AUTH_FIELD == "email":
params = {"email": username, "password": password}
params["service"] = service
encoded_params = urlencode([(k, smart_str(v, "latin1")) for k, v in params.items()])
try:
# get the user's data from the api
xml = urlopen(url + encoded_params).read()
userinfo = dict((e.tag, smart_unicode(e.text, strings_only=True))
for e in ET.fromstring(xml).getchildren())
if "nil" in userinfo:
return userinfo
else:
return None
So, we get the xml, parse it into a dict and if the key nil is present
then we can return the dict and carry on happy and authenticated.
Clearly, one solution is just to find a way to somehow override or
monkeypatch the logic in the xml variable, I found this answer:
How can one mock/stub python module like urllib
I tried to implement something like that, but the details there are
very sketchy and I couldn't seem to get that working.
I also captured the xml response and put it in a local file in the
test folder with the intention of finding a way to use that as a mock
response that is passed into the url parameter of the test function,
something like this will override the url:
#override_settings(AUTHENTICATE_URL_VIA_PASSWORD=(os.path.join(os.path.dirname(__file__), "{0}".format("response.xml"))))
def test_get_user_info_username(self):
self.backend = RemoteAuthBackend()
self.backend.get_info_from_api_with_un_pw("user", "pass")
But that also needs to take account of the url building logic that the
function defines, (i.e. "url + encoded_params"). Again, I could rename
the response file to be the same as the concatenated url but this is becoming
less like a good unit-test for the function and more of a "cheat", the whole
thing is just getting more and more brittle all the time with these solutions, and its really just a fixture anyway, which is also something I want to avoid if
at all possible.
I also wondered if there might be a way to serve the xml on the django development server and then point the function at that? It seems like a saner solution, but much googling gave me no clues if such a thing would be possible or advisable and even then I don't think that would be a test to run outside of the development environment.
So, ideally, I need to be able to somehow mock a "server" to
take the place of the Java API in the function call, or somehow serve
up some xml payload that the function can open as its url, or
monkeypatch the function from the test itself, or...
Does the mock library have the appropriate tools to do such things?
http://www.voidspace.org.uk/python/mock
So, there are two points to this question 1) I would like to solve my
particular problem in a clean way, and more importantly 2) what are
the best practices for cleanly writing Django unit-tests when you are
dependent on data, cookies, etc. for user authentication from a remote
API that is outside of your domain?

The mock library should work if used properly. I prefer the minimock library and I wrote a small base unit testcase (minimocktest) that helps with this.
If you want to integrate this testcase with Django to test urllib you can do it as follows:
from minimocktest import MockTestCase
from django.test import TestCase
from django.test.client import Client
class DjangoTestCase(TestCase, MockTestCase):
'''
A TestCase class that combines minimocktest and django.test.TestCase
'''
def _pre_setup(self):
MockTestCase.setUp(self)
TestCase._pre_setup(self)
# optional: shortcut client handle for quick testing
self.client = Client()
def _post_teardown(self):
TestCase._post_teardown(self)
MockTestCase.tearDown(self)
Now you can use this testcase instead of using the Django test case directly:
class MySimpleTestCase(DjangoTestCase):
def setUp(self):
self.file = StringIO.StringIO('MiniMockTest')
self.file.close = self.Mock('file_close_function')
def test_urldump_dumpsContentProperly(self):
self.mock('urllib2.urlopen', returns=self.file)
self.assertEquals(urldump('http://pykler.github.com'), 'MiniMockTest')
self.assertSameTrace('\n'.join([
"Called urllib2.urlopen('http://pykler.github.com')",
"Called file_close_function()",
]))
urllib2.urlopen('anything')
self.mock('urllib2.urlopen', returns=self.file, tracker=None)
urllib2.urlopen('this is not tracked')
self.assertTrace("Called urllib2.urlopen('anything')")
self.assertTrace("Called urllib2.urlopen('this is mocked but not tracked')", includes=False)
self.assertSameTrace('\n'.join([
"Called urllib2.urlopen('http://pykler.github.com')",
"Called file_close_function()",
"Called urllib2.urlopen('anything')",
]))

Here's the basics of the solution that I ended up with for the record. I used the Mock library itself rather than Mockito in the end, but the idea is the same:
from mock import patch
#override_settings(AUTHENTICATE_LOGIN_FIELD="username")
#patch("mymodule.auth_backend.urlopen")
def test_get_user_info_username(self, urlopen_override):
response = "file://" + os.path.join(os.path.dirname(__file__), "{0}".format("response.xml"))
# mock patch replaces API call
urlopen_override.return_value = urlopen(response)
# call the patched object
userinfo = RemoteAuthBackend.get_info_from_api_with_un_pw("user", "pass")
assert_equal(type(userinfo), dict)
assert_equal(userinfo["nick"], "user")
assert_equal(userinfo["pass"], "pass")

How do I expose a PyAMF service?

I've created a service called 'timesTwo' and dropped the file in the correct directory. When I try and call it from my client-side code however, it tells me that the service doesn't exist. Once I've created my server side code, how do I expose the service? What step(s) am I missing?
Server-side code:
from pyamf.remoting.gateway.wsgi import WSGIGateway
def timesTwo(data):
return data * 2
services = {
'timesTwo': timesTwo,
# Add other exposed functions here
}
gateway = WSGIGateway(services)
I'm having a really hard time finding online documentation. Thanks for the help!
Sidenote: Is there some resource (website, book, ANYthing) that would be more thorough than what's on pyamf.org that you would recommend?!

Is there a direct equivalent to httplib.HTTPConnection() in httplib2

I'm trying to get rid of an exception HTTPException('ApplicationError: 5 ',) I get when using httplib in a python27 API (running on google appengine) - further detailed in this post ApplicationError2 and ApplicationError5 when communicating with external api from AppEngine . I thought that I could perhaps instead try using httplib2. The only part of the API which makes a call to httplib that I can see is:
def _get_conn(self):
return httplib.HTTPConnection(str(self.host), str(self.port), timeout=120)
Is there a direct equivalent to httplib.HTTPConnection() in httplib2? I've had a search but cannot find anything.

It seems there is, see AppEngineHttpConnection in http2 source code.
However, AFAIK those are not part of the official httplib2 API as shown in their documentation, you'd rather do something like:
import httplib2
h = httplib2.Http()
resp, content = h.request("http://bitworking.org/")
assert resp.status == 200
assert resp['content-type'] == 'text/html'
Have you considered using Request library, it is getting a lot of good press recently.

Creating a mock web service from a WSDL file in Python

We are writing a client for a remote service that exposes SOAP web services and publishes a WSDL definition for those services.
We don't have access to the system during testing, so we'd like to write a mock service. We're using Python for the client, so ideally we'd want to use Python for the mock server, although I suppose it's not strictly necessary.
The dream would be to be able to generate stubs from the WSDL file which we could fill in, and then serve those using Paste Deploy as a WSGI server, although it doesn't have to be Paste Deploy or WSGI so long as it works reliably. The main thing is that we need to be generating the stubs from the "real" WSDL file so that we don't accidentally write a non-compliant mock server.
We're using suds for the client side library, and have looked at soaplib and ZSI. However, the wsgi2py stuff in soaplib says "do not use" at the top and ZSI seems like a lot to swallow. What do people generally use for this kind of thing?
Martin

As a mock server I would really recommend soapUI (http://www.soapui.org).
It takes a WSDL and generates the services and service methods automatically. You can then go on and define static returns or dynamic ones using Groovy scripts. Take a look here for the documentation of web service mocking.
soapUI comes in a free and paid pro version. I have used the free version with great success.

I would recommend you use soapUI for creating a mock service. It's very easy to install. It's just as easy to create a WS mock service.
It takes the WSDL file from your desired location, it creates the structure for the requests and if you wish, it also creates the mock web service with the intended structure drawn from the WSDL file.
When you create the new soapUI project, select the third checkbox option to create the mock web service.
If xsd schema files are required, make sure they are well referenced from the WSDL file.
It doesn't use python but if all you need is a test environment that you can send requests and get responses, that will be more than enough.
I hope that helps.

You could use this code for creating a suds mock client.
from suds.client import Client
class AlwaysCallable(object):
"""
Represents a chainable-access object and proxies calls to ClientMock.
"""
name = None
def __init__(self, client_cls):
self._client_cls = client_cls
def __call__(self, *args, **kwargs):
try:
hook = object.__getattribute__(self._client_cls, self.name)
except AttributeError:
pass
else:
return hook(self._client_cls, *args, **kwargs)
def __getattr__(self, item):
new = object.__getattribute__(self, '__class__')(self._client_cls)
new.name = item
return new
class ClientMock(Client):
"""
Abstract mock suds client.
"""
def __init__(self, url, **kwargs):
pass
def __getattr__(self, item):
return AlwaysCallable(self.__class__)
def __unicode__(self):
return 'Client mock'
def __str__(self):
return 'Client mock'
And next define a concrete ClientMock.
class UserCredentialsServiceClientMock(ClientMock):
"""
Mock object that implements remote side services.
"""
def GetUserInfo(cls, user_id):
"""
Stub for remote service.
"""
return UserInfo(id=user_id, name='Adam Smith')
Now you could use mock library to spoof a code, that uses suds.client.Client.
from unittest import TestCase
from mock import patch
from project.api import get_user_credentials
class UserCredentialsClientTestCase(TestCase):
def test_getting_user_credentials(self):
with patch('project.api.Client', new=UserCredentialsServiceClientMock):
self.assertEquals(get_user_credentials(1), 'Adam Smith')