[Django]-How to test custom django-admin commands

by

128👍

✅

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

👤Jorge E. Cardona

23👍

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.

👤Daniel Roseman

20👍

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.")
👤madjardi

7👍

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
👤asfor

-1👍

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')
👤Bosco

-3👍

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.

👤Aaron Vernon

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