TransactionManagementError "You can't execute queries until the end of the 'atomic' block" while using signals, but only during Unit Testing


I am getting TransactionManagementError when trying to save a Django User model instance and in its post_save signal, I’m saving some models that have the user as the foreign key.

The context and error is pretty similar to this question
django TransactionManagementError when using signals

However, in this case, the error occurs only while unit testing.

It works well in manual testing, but unit tests fails.

Is there anything that I’m missing?

Here are the code snippets:

def mobileRegister(request):
    if request.method == 'GET':
        response = {"error": "GET request not accepted!!"}
        return HttpResponse(json.dumps(response), content_type="application/json",status=500)
    elif request.method == 'POST':
        postdata = json.loads(request.body)
            # Get POST data which is to be used to save the user
            username = postdata.get('phone')
            password = postdata.get('password')
            email = postdata.get('email',"")
            first_name = postdata.get('first_name',"")
            last_name = postdata.get('last_name',"")
            user = User(username=username, email=email,
                        first_name=first_name, last_name=last_name)
            user._company = postdata.get('company',None)
            user._country_code = postdata.get('country_code',"+91")
            user._gcm_reg_id = postdata.get('reg_id',None)
            user._gcm_device_id = postdata.get('device_id',None)
            # Set Password for the user
            # Save the user

def create_user_profile(sender, instance, created, **kwargs):
    if created:
        company = None
        companycontact = None
        try:   # Try to make userprofile with company and country code provided
            user = User.objects.get(
            rand_pass = random.randint(1000, 9999)
            company = Company.objects.get_or_create(name=instance._company,user=user)
            companycontact = CompanyContact.objects.get_or_create(contact_type="Owner",company=company,contact_number=instance.username)
            profile = UserProfile.objects.get_or_create(user=instance,phone=instance.username,verification_code=rand_pass,company=company,country_code=instance._country_code)
            gcmDevice = GCMDevice.objects.create(registration_id=instance._gcm_reg_id,device_id=instance._gcm_reg_id,user=instance)
        except Exception, e:

class AuthTestCase(TestCase):
    fixtures = ['nextgencatalogs/fixtures.json']
    def setUp(self):

    def test_registration_api_get(self):
        response = self.client.get("/mobileRegister/")

    def test_registration_api_post(self):
        response ="/mobileRegister/",
        user = User.objects.get(username=self.user_data['username'])
        # Check if the company was created
        company = Company.objects.get(user__username=self.user_data['phone'])
        # Check if the owner's contact is the same as the user's phone number
        company_contact = CompanyContact.objects.get(company=company,contact_type="owner")


ERROR: test_registration_api_post (nextgencatalogs.apps.catalogsapp.tests.AuthTestCase)
Traceback (most recent call last):
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/nextgencatalogs/apps/catalogsapp/", line 29, in test_registration_api_post
    user = User.objects.get(username=self.user_data['username'])
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/", line 151, in get
    return self.get_queryset().get(*args, **kwargs)
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/", line 301, in get
    num = len(clone)
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/", line 77, in __len__
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/", line 854, in _fetch_all
    self._result_cache = list(self.iterator())
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/", line 220, in iterator
    for row in compiler.results_iter():
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/sql/", line 710, in results_iter
    for rows in self.execute_sql(MULTI):
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/models/sql/", line 781, in execute_sql
    cursor.execute(sql, params)
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/backends/", line 47, in execute
  File "/Users/gauravtoshniwal1989/Developer/Web/Server/ngc/ngcvenv/lib/python2.7/site-packages/django/db/backends/", line 365, in validate_no_broken_transaction
    "An error occurred in the current transaction. You can't "
TransactionManagementError: An error occurred in the current transaction. You can't execute queries until the end of the 'atomic' block.

Asked By: Gaurav Toshniwal



I ran into this same problem myself. This is caused by a quirk in how transactions are handled in the newer versions of Django coupled with a unittest that intentionally triggers an exception.

I had a unittest that checked to make sure a unique column constraint was enforced by purposefully triggering an IntegrityError exception:

def test_constraint(self):
        # Duplicates should be prevented.
        models.Question.objects.create(domain=self.domain, slug='barks')'Duplicate question allowed.')
    except IntegrityError:


In Django 1.4, this works fine. However, in Django 1.5/1.6, each test is wrapped in a transaction, so if an exception occurs, it breaks the transaction until you explicitly roll it back. Therefore, any further ORM operations in that transaction, such as my do_more_model_stuff(), will fail with that django.db.transaction.TransactionManagementError exception.

Like caio mentioned in the comments, the solution is to capture your exception with transaction.atomic like:

from django.db import transaction
def test_constraint(self):
        # Duplicates should be prevented.
        with transaction.atomic():
            models.Question.objects.create(domain=self.domain, slug='barks')'Duplicate question allowed.')
    except IntegrityError:

That will prevent the purposefully-thrown exception from breaking the entire unittest’s transaction.

Answered By: Cerin

Since @mkoistinen never made his comment an answer, I’ll post his suggestion so people won’t have to dig through comments.

consider just declaring your test class as a TransactionTestCase rather than just TestCase.

From the Django docs: A TransactionTestCase may call commit and rollback and observe the effects of these calls on the database.

Answered By: kdazzle

I had the same issue.

In My Case I was doing this


so converting it to


Removed that error.

Answered By: Diaa Mohamed Kasem

I was getting this error on running unit tests in my create_test_data function using django 1.9.7. It worked in earlier versions of django.

It looked like this:

cls.localauth,_ = Organisation.objects.get_or_create(organisation_type=cls.orgtypeLA, name='LA for test', email_general='[email protected]', address='test', postcode='test', telephone='test')
cls.chamber,_ = Organisation.objects.get_or_create(organisation_type=cls.orgtypeC, name='chamber for test', email_general='[email protected]', address='test', postcode='test', telephone='test')
cls.lawfirm,_ = Organisation.objects.get_or_create(organisation_type=cls.orgtypeL, name='lawfirm for test', email_general='[email protected]', address='test', postcode='test', telephone='test') = True = True    <---- error here = True

My solution was to use update_or_create instead:

cls.localauth,_ = Organisation.objects.update_or_create(organisation_type=cls.orgtypeLA, name='LA for test', email_general='[email protected]', address='test', postcode='test', telephone='test', defaults={'active': True})
cls.chamber,_ = Organisation.objects.update_or_create(organisation_type=cls.orgtypeC, name='chamber for test', email_general='[email protected]', address='test', postcode='test', telephone='test', defaults={'active': True})
cls.lawfirm,_ = Organisation.objects.update_or_create(organisation_type=cls.orgtypeL, name='lawfirm for test', email_general='[email protected]', address='test', postcode='test', telephone='test', defaults={'active': True})
Answered By: PhoebeB

I have the same issue, but with transaction.atomic() and TransactionTestCase didn’t work for me.

python test -r instead of python test is ok for me, maybe the order of execution is crucial

then i find a doc about Order in which tests are executed, It mentions which test will run first.

So, i use TestCase for database interaction, unittest.TestCase for other simple test, it works now!

Answered By: Leo

For me, the proposed fixes did not work. In my tests, I open some subprocesses with Popen to analyze/lint migrations (e.g. one test checks if there are no model changes).

For me, subclassing from SimpleTestCase instead of TestCase did do the trick.

Note that SimpleTestCase doesn’t allow to use the database.

While this does not answer the original question, I hope this helps some people anyway.

Answered By: flix

The answer of @kdazzle is correct. I didnt try it because people said that ‘Django’s TestCase class is a more commonly used subclass of TransactionTestCase’ so I thought it was the same use one or another. But the blog of Jahongir Rahmonov explained it better:

the TestCase class wraps the tests within two nested atomic() blocks:
one for the whole class and one for each test. This is where
TransactionTestCase should be used. It does not wrap the tests with
atomic() block and thus you can test your special methods that require
a transaction without any problem.

EDIT: It didn’t work, I thought yes, but NO.

In 4 years they could fixed this…………………………………

Answered By: Shil Nevado

If using pytest-django you can pass transaction=True to the django_db decorator to avoid this error.


Django itself has the TransactionTestCase which allows you to test
transactions and will flush the database between tests to isolate
them. The downside of this is that these tests are much slower to set up due to the required flushing of the database. pytest-django also supports this style of tests, which you can select using an argument to the django_db mark:

def test_spam():
    pass  # test relying on transactions
Answered By: frmdstryr

Here is another way to do it, based on the answer to this question:

with transaction.atomic():
    self.assertRaises(IntegrityError, models.Question.objects.create, **{'domain':self.domain, 'slug':'barks'})
Answered By: Mahdi Hamzeh
def test_wrong_user_country_db_constraint(self):
        Check whether or not DB constraint doesnt allow to save wrong country code in DB.
        self.test_user_data['user_country'] = 'XX'
        expected_constraint_name = "country_code_within_list_of_countries_check"

        with transaction.atomic():
            with self.assertRaisesRegex(IntegrityError, expected_constraint_name) as cm:

with transaction.atomic() seems do the job correct
Answered By: Aleksei Khatkevich

In my case it was caused but not calling super().tearDownClass()

class TnsFileViewSetTestCase(APITestCase):
    def tearDownClass(self):
        super().tearDownClass()    # without this line we will get TransactionManagementError
        for tnsfile in TnsFile.objects.all():
Answered By: Artem Bernatskyi