I created custom django-admin commands
But, I don't know how to test it in standard django tests
If you're using some coverage tool it would be good to call it from the code with:
from django.core.management import call_command
from django.test import TestCase
class CommandsTestCase(TestCase):
def test_mycommand(self):
" Test my custom command."
args = []
opts = {}
call_command('mycommand', *args, **opts)
# Some Asserts.
From the official documentation
Management commands can be tested with the call_command() function. The output can be redirected into a StringIO instance
You should make your actual command script the minimum possible, so that it just calls a function elsewhere. The function can then be tested via unit tests or doctests as normal.
you can see in github.com example
see here
def test_command_style(self):
out = StringIO()
management.call_command('dance', style='Jive', stdout=out)
self.assertEquals(out.getvalue(),
"I don't feel like dancing Jive.")
To add to what has already been posted here. If your django-admin command passes a file as parameter, you could do something like this:
from django.test import TestCase
from django.core.management import call_command
from io import StringIO
import os
class CommandTestCase(TestCase):
def test_command_import(self):
out = StringIO()
call_command(
'my_command', os.path.join('path/to/file', 'my_file.txt'),
stdout=out
)
self.assertIn(
'Expected Value',
out.getvalue()
)
This works when your django-command is used in a manner like this:
$ python manage.py my_command my_file.txt
A simple alternative to parsing stdout is to make your management command exit with an error code if it doesn't run successfully, for example using sys.exit(1).
You can catch this in a test with:
with self.assertRaises(SystemExit):
call_command('mycommand')
I agree with Daniel that the actual command script should do the minimum possible but you can also test it directly in a Django unit test using os.popen4.
From within your unit test you can have a command like
fin, fout = os.popen4('python manage.py yourcommand')
result = fout.read()
You can then analyze the contents of result to test whether your Django command was successful.
Related
I have searched the stackoverflow and wasn't able to find this. I have noticed something I can not wrap my head around. When run as normal python script import works ok, but when run from Django shell it behaves weird, needs to set import as global to be seen.
You can reproduce it like this. Make a file test.py in folder with manage.py. Code you can test with is this.
This doesn't work, code of test.py:
#!/usr/bin/env python3
import chardet
class LoadList():
def __init__(self):
self.email_list_path = '/home/omer/test.csv'
#staticmethod
def check_file_encoding(file_to_check):
encoding = chardet.detect(open(file_to_check, "rb").read())
return encoding
def get_encoding(self):
return self.check_file_encoding(self.email_list_path)['encoding']
print(LoadList().get_encoding())
This works ok when chardet set as global inside test.py file:
#!/usr/bin/env python3
import chardet
class LoadList():
def __init__(self):
self.email_list_path = '/home/omer/test.csv'
#staticmethod
def check_file_encoding(file_to_check):
global chardet
encoding = chardet.detect(open(file_to_check, "rb").read())
return encoding
def get_encoding(self):
return self.check_file_encoding(self.email_list_path)['encoding']
print(LoadList().get_encoding())
First run is without global chardet and you can see the error. Second run is with global chardet set and you can see it works ok.
What is going on and can someone explain this to me? Why it isn't seen until set as global?
Piping a file into shell is the same as piping it into the python command. It's not the same as running the file with python test.py. I suspect it's something to do with the way the the newlines are interpreted as to how the file is really parsed, but don't have time to check.
Instead of this approach I'd recommend you write a custom management command.
I want to test how a project generated by cookiecutter behave with multiple invocation patterns.
Given the following generated project
proj/
proj/
__init__.py
__main__.py
Content of __init__.py:
def func():
pass
Content of __main__.py:
from proj import func
def main():
func()
if __name__ == '__main__':
main()
(I have read about issues of __main__.__spec__, this is not what this question is about. In fact, I would like to test-drive -TDD- my work arounds of these issues)
Now I write tests in which the generated project structure and location is known (available via pytest fixtures, for instance)
test_run_proj_script():
"""Test behavior of ``python3 ./proj``"""
pass # how to run this?
test_run_proj_module():
"""Test behavior of ``python3 -m ./proj``"""
pass # how to run this?
Bonus: inject values for sys.argv ?
I would like to compute some information in my Django application on regular basis.
I need to select and insert data each second and want to use Django ORM.
How can I do this?
In a shell script, set the DJANGO_SETTINGS_MODULE variable and call a python script
export DJANGO_SETTINGS_MODULE=yourapp.settings
python compute_some_info.py
In compute_some_info.py, set up django and import your modules (look at how the manage.py script sets up to run Django)
#!/usr/bin/env python
import sys
try:
import settings # Assumed to be in the same directory.
except ImportError:
sys.stderr.write("Error: Can't find the file 'settings.py'")
sys.exit(1)
sys.path = sys.path + ['/yourapphome']
from yourapp.models import YourModel
YourModel.compute_some_info()
Then call your shell script in a cron job.
Alternatively -- you can just keep running and sleeping (better if it's every second) -- you would still want to be outside of the webserver and in your own process that is set up this way.
One way to do it would be to create a custom command, and invoke python manage.py your_custom_command from cron or windows scheduler.
http://docs.djangoproject.com/en/dev/howto/custom-management-commands/
For example, create myapp/management/commands/myapp_task.py which reads:
from django.core.management.base import NoArgsCommand
class Command(NoArgsCommand):
def handle_noargs(self, **options):
print 'Doing task...'
# invoke the functions you need to run on your project here
print 'Done'
Then you can run it from cron like this:
export DJANGO_SETTINGS_MODULE=myproject.settings; export PYTHONPATH=/path/to/project_parent; python manage.py myapp_task
If I run the following command:
>python manage.py test
Django looks at tests.py in my application, and runs any doctests or unit tests in that file. It also looks at the __ test __ dictionary for extra tests to run. So I can link doctests from other modules like so:
#tests.py
from myapp.module1 import _function1, _function2
__test__ = {
"_function1": _function1,
"_function2": _function2
}
If I want to include more doctests, is there an easier way than enumerating them all in this dictionary? Ideally, I just want to have Django find all doctests in all modules in the myapp application.
Is there some kind of reflection hack that would get me where I want to be?
I solved this for myself a while ago:
apps = settings.INSTALLED_APPS
for app in apps:
try:
a = app + '.test'
__import__(a)
m = sys.modules[a]
except ImportError: #no test jobs for this module, continue to next one
continue
#run your test using the imported module m
This allowed me to put per-module tests in their own test.py file, so they didn't get mixed up with the rest of my application code. It would be easy to modify this to just look for doc tests in each of your modules and run them if it found them.
Use django-nose since nose automatically find all tests recursivelly.
Here're key elements of solution:
tests.py:
def find_modules(package):
"""Return list of imported modules from given package"""
files = [re.sub('\.py$', '', f) for f in os.listdir(os.path.dirname(package.__file__))
if f.endswith(".py") and os.path.basename(f) not in ('__init__.py', 'test.py')]
return [imp.load_module(file, *imp.find_module(file, package.__path__)) for file in files]
def suite(package=None):
"""Assemble test suite for Django default test loader"""
if not package: package = myapp.tests # Default argument required for Django test runner
return unittest.TestSuite([doctest.DocTestSuite(m) for m in find_modules(package)])
To add recursion use os.walk() to traverse module tree and find python packages.
Thanks to Alex and Paul. This is what I came up with:
# tests.py
import sys, settings, re, os, doctest, unittest, imp
# import your base Django project
import myapp
# Django already runs these, don't include them again
ALREADY_RUN = ['tests.py', 'models.py']
def find_untested_modules(package):
""" Gets all modules not already included in Django's test suite """
files = [re.sub('\.py$', '', f)
for f in os.listdir(os.path.dirname(package.__file__))
if f.endswith(".py")
and os.path.basename(f) not in ALREADY_RUN]
return [imp.load_module(file, *imp.find_module(file, package.__path__))
for file in files]
def modules_callables(module):
return [m for m in dir(module) if callable(getattr(module, m))]
def has_doctest(docstring):
return ">>>" in docstring
__test__ = {}
for module in find_untested_modules(myapp.module1):
for method in modules_callables(module):
docstring = str(getattr(module, method).__doc__)
if has_doctest(docstring):
print "Found doctest(s) " + module.__name__ + "." + method
# import the method itself, so doctest can find it
_temp = __import__(module.__name__, globals(), locals(), [method])
locals()[method] = getattr(_temp, method)
# Django looks in __test__ for doctests to run
__test__[method] = getattr(module, method)
I'm not up to speed on Djano's testing, but as I understand it uses automatic unittest discovery, just like python -m unittest discover and Nose.
If so, just put the following file somewhere the discovery will find it (usually just a matter of naming it test_doctest.py or similar).
Change your_package to the package to test. All modules (including subpackages) will be doctested.
import doctest
import pkgutil
import your_package as root_package
def load_tests(loader, tests, ignore):
modules = pkgutil.walk_packages(root_package.__path__, root_package.__name__ + '.')
for _, module_name, _ in modules:
try:
suite = doctest.DocTestSuite(module_name)
except ValueError:
# Presumably a "no docstrings" error. That's OK.
pass
else:
tests.addTests(suite)
return tests
I want to write a unit test for a Django manage.py command that does a backend operation on a database table. How would I invoke the management command directly from code?
I don't want to execute the command on the Operating System's shell from tests.py because I can't use the test environment set up using manage.py test (test database, test dummy email outbox, etc...)
The best way to test such things - extract needed functionality from command itself to standalone function or class. It helps to abstract from "command execution stuff" and write test without additional requirements.
But if you by some reason cannot decouple logic form command you can call it from any code using call_command method like this:
from django.core.management import call_command
call_command('my_command', 'foo', bar='baz')
Rather than do the call_command trick, you can run your task by doing:
from myapp.management.commands import my_management_task
cmd = my_management_task.Command()
opts = {} # kwargs for your command -- lets you override stuff for testing...
cmd.handle_noargs(**opts)
the following code:
from django.core.management import call_command
call_command('collectstatic', verbosity=3, interactive=False)
call_command('migrate', 'myapp', verbosity=3, interactive=False)
...is equal to the following commands typed in terminal:
$ ./manage.py collectstatic --noinput -v 3
$ ./manage.py migrate myapp --noinput -v 3
See running management commands from django docs.
The Django documentation on the call_command fails to mention that out must be redirected to sys.stdout. The example code should read:
from django.core.management import call_command
from django.test import TestCase
from django.utils.six import StringIO
import sys
class ClosepollTest(TestCase):
def test_command_output(self):
out = StringIO()
sys.stdout = out
call_command('closepoll', stdout=out)
self.assertIn('Expected output', out.getvalue())
Building on Nate's answer I have this:
def make_test_wrapper_for(command_module):
def _run_cmd_with(*args):
"""Run the possibly_add_alert command with the supplied arguments"""
cmd = command_module.Command()
(opts, args) = OptionParser(option_list=cmd.option_list).parse_args(list(args))
cmd.handle(*args, **vars(opts))
return _run_cmd_with
Usage:
from myapp.management import mycommand
cmd_runner = make_test_wrapper_for(mycommand)
cmd_runner("foo", "bar")
The advantage here being that if you've used additional options and OptParse, this will sort the out for you. It isn't quite perfect - and it doesn't pipe outputs yet - but it will use the test database. You can then test for database effects.
I am sure use of Micheal Foords mock module and also rewiring stdout for the duration of a test would mean you could get some more out of this technique too - test the output, exit conditions etc.
The advanced way to run manage command with a flexible arguments and captured output
argv = self.build_argv(short_dict=kwargs)
cmd = self.run_manage_command_raw(YourManageCommandClass, argv=argv)
# Output is saved cmd.stdout.getvalue() / cmd.stderr.getvalue()
Add code to your base Test class
#classmethod
def build_argv(cls, *positional, short_names=None, long_names=None, short_dict=None, **long_dict):
"""
Build argv list which can be provided for manage command "run_from_argv"
1) positional will be passed first as is
2) short_names with be passed after with one dash (-) prefix
3) long_names with be passed after with one tow dashes (--) prefix
4) short_dict with be passed after with one dash (-) prefix key and next item as value
5) long_dict with be passed after with two dashes (--) prefix key and next item as value
"""
argv = [__file__, None] + list(positional)[:]
for name in short_names or []:
argv.append(f'-{name}')
for name in long_names or []:
argv.append(f'--{name}')
for name, value in (short_dict or {}).items():
argv.append(f'-{name}')
argv.append(str(value))
for name, value in long_dict.items():
argv.append(f'--{name}')
argv.append(str(value))
return argv
#classmethod
def run_manage_command_raw(cls, cmd_class, argv):
"""run any manage.py command as python object"""
command = cmd_class(stdout=io.StringIO(), stderr=io.StringIO())
with mock.patch('django.core.management.base.connections.close_all'):
# patch to prevent closing db connecction
command.run_from_argv(argv)
return command