writing unit test for many to many model in django program - django

in my django projects, I have a two class like following:
class DataTag(models.Model):
title = models.CharField(max_length=120, unique=True)
relations = models.ManyToManyField('DataTag',
related_name='related_data_tags', blank=True)
and the another class is:
class Data(models.Model):
tags = models.ManyToManyField('DataTag',related_name = 'data')
def tag_name(self):
if self.tags.all():
return self.tags.all()[0].title
return ''
both my models work, but now I want to write a test for main_tag_name, and checking if this function returns a true value or not.until now I write the following:
from unittest import TestCase
class DataTest(TestCase):
def test_tag_name(self):
self.data = Data.objects.create()
self.tag1 = DataTag.objects.create()
I am new on writing test. please help me for writing this test.
Thanks in advance

What you can do:
Create a Data object:
data_object = Data.objects.create()
Now, create a tag for this:
data_object.tags.create(name='Foo')
You can assert that the relationship exists: self.assertTrue(data_objects.tags.exists())
And now you can assert that tag_name returns what you expect: self.assertEqual(data_object.tag_name, 'Foo')

Related

Create A Many-To-Many Relationship In A Test

I have a many-to-many relationship:
class Person(models.Model):
modules = models.ManyToManyField(BaseModule, blank=True)
class BaseModule(models.Model):
task_type = models.CharField(max_length=200)
topic = models.CharField(max_length=200)
I am loading in my fixtures test data, populating my 'BaseModule' database:
fixtures = ['test/fixtures/initial_data.json']
Then creating a User object, but I cant figure out how to create a relationship between a User and BaseModule.
Ive tried many things, including:
# this works, but creates a new BaseModule, I want to create a relationship with one generated in 'fixtures'
test = person.modules.create(topic='test')
test.save()
# this doesnt work
testModule = BaseModule.objects.get(pk=1)
person.modules.set(testModule)
# this doesnt work either
person.modules.create()
person.modules.basemodule_id = 1
person.refresh_from_db()
for module in person.modules.all():
print("module.topic:")
print(module.topic)
print("end")
Thank you.
#this doesnt work
testModule = BaseModule.objects.get(pk=1)
person.modules.set(testModule)
You should add brackets []
testModule = BaseModule.objects.get(pk=1)
person.modules.set([testModule])

Not able to initialise choice fields in Unit test for django form where choice field is getting populated from db

I have one django form where a choice field is getting populated from db.
class TestForm(forms.Form):
CLASS_CHOICE = []
classes = Class.objects.filter(std__gte=4)
for cls in classes:
CLASS_CHOICE.append((cls.code,
"{} - {}".format(cls.code,cls.std)))
name = forms.CharField()
class = forms.ChoiceField(choices = CLASS_CHOICE)
def _post_clean(self):
# some validation
pass
When writing its unit test as:
class SampleTest(TestCase):
#classmethod
def setUpClass(cls):
super(SampleTest, cls).setUpClass()
cls.class = Class.objects.create(std=10,code='A')
def test_valid_form(self):
post_data = {'name':'testing',
'class':'A' }
f = TestForm(data=post_data)
self.assertTrue(f.is_valid())
Now the problem is, when running test, the application is loaded first before initializing db hence the setUpClass for unit test is not getting called and CLASS_CHOICE remains blank and form validation is getting failed. How can I avoid this or reinitialize choice field after i create one entry in Class table.
The way you have it set up the class choices are only going to be populated once, when the module containing your code is executed for the first time. This is less than ideal because:
if new classes are added they will not be available as choice options
the database may not be connected when this module is loaded into memory, causing runtime errors
You need to make it so that choices is built dynamically every time a new form is created. To do this make choices a callable function rather than a list:
def get_class_choices():
class_choice = []
classes = Class.objects.filter(std__gte=4)
for cls in classes:
class_choice.append((cls.code, "{} - {}".format(cls.code, cls.std)))
return class_choice
class TestForm(forms.Form):
name = forms.CharField()
class = forms.ChoiceField(choices=get_class_choices)
def _post_clean(self):
# some validation
pass

use django_filters to filter for multiple arguments

I am using Relay, Django, Graphene Graphql.
I would like to use django_filters to filter for multiple arguments of type on accommodation. This is described in my schema file and atm looks like:
class AccommodationNode(DjangoObjectType) :
class Meta:
model = Accommodation
interfaces = (relay.Node,)
filter_fields = ['type']
This works perfectly if I pass a single string like: {"accommodationType": "apartment"}, but what if I want to filter for all accommodations that are apartments OR hotels? something like: {"accommodationType": ["apartment","hotel"]}
This is my model:
class Accommodation(models.Model):
ACCOMMODATION_TYPE_CHOICES = (
('apartment', 'Apartment'),
('host_family', 'Host Family'),
('residence', 'Residence'),
)
school = models.ForeignKey(School, on_delete=models.CASCADE, related_name='accommodations')
type = models.CharField(
max_length=200,
choices=ACCOMMODATION_TYPE_CHOICES,
default='apartment'
)
def __str__(self):
return str(self.school) + " - " + self.type
Is there any way I can do this without writing custom filters as are suggested here? For only one filter field this is a great solution but I'll end up having around 50 throughout my application including linked objects...
Have a look at Django REST Framework Filters:
https://github.com/philipn/django-rest-framework-filters
It supports more than exact matches, like in, which you are looking for, but also exact, startswith, and many more, in the same style of Django's ORM. I use it frequently and have been impressed - it even integrates with DRF's web browseable API. Good luck!
like FlipperPA mentioned, I need to use 'in'. According to the django_filter docs:
‘in’ lookups return a filter derived from the CSV-based BaseInFilter.
and an example of BaseInFilter in the docs:
class NumberRangeFilter(BaseInFilter, NumberFilter):
pass
class F(FilterSet):
id__range = NumberRangeFilter(name='id', lookup_expr='range')
class Meta:
model = User
User.objects.create(username='alex')
User.objects.create(username='jacob')
User.objects.create(username='aaron')
User.objects.create(username='carl')
# Range: User with IDs between 1 and 3.
f = F({'id__range': '1,3'})
assert len(f.qs) == 3
The answer to my question:
class AccommodationNode(DjangoObjectType) :
class Meta:
model = Accommodation
interfaces = (relay.Node,)
filter_fields = {
'type': ['in']
}
With the argument {"accommodationType": "apartment,hotel"} will work

how to select boolean fields in django model

I have 2 models in different apps:
class Stock(models.Model):
vsej_seti = models.BooleanField(default=False, verbose_name=_('Все сети'))
and
class Hotel(ServioResource):
stock_all = models.ForeignKey('content.Stock', related_name='st', null=True, blank=True)
Please help me to write a method which sort all booleanfields with true parametr. In sql it looks like "SELECT * FROM content_stock WHERE vsej_seti=1". I wrote smth like this, but it doesn't work. Thanks
def qqq(self):
f = False
if self.stock_all.vsej_seti == f:
return self.stock_all.vsej_seti
You can just use a queryset filter
def qqq(self):
return self.stock_all.filter(vsej_seti=True)
Note: There may be more efficient queries avaiable depending on your use case but this is easily modified as per the docs

Django Tests: setUpTestData on Postgres throws: "Duplicate key value violates unique constraint"

I am running into a database issue in my unit tests. I think it has something to do with the way I am using TestCase and setUpData.
When I try to set up my test data with certain values, the tests throw the following error:
django.db.utils.IntegrityError: duplicate key value violates unique constraint
...
psycopg2.IntegrityError: duplicate key value violates unique constraint "InventoryLogs_productgroup_product_name_48ec6f8d_uniq"
DETAIL: Key (product_name)=(Almonds) already exists.
I changed all of my primary keys and it seems to be running fine. It doesn't seem to affect any of the tests.
However, I'm concerned that I am doing something wrong. When it first happened, I reversed about an hour's worth of work on my app (not that much code for a noob), which corrected the problem.
Then when I wrote the changes back in, the same issue presented itself again. TestCase is pasted below. The issue seems to occur after I add the sortrecord items, but corresponds with the items above it.
I don't want to keep going through and changing primary keys and urls in my tests, so if anyone sees something wrong with the way I am using this, please help me out. Thanks!
TestCase
class DetailsPageTest(TestCase):
#classmethod
def setUpTestData(cls):
cls.product1 = ProductGroup.objects.create(
product_name="Almonds"
)
cls.variety1 = Variety.objects.create(
product_group = cls.product1,
variety_name = "non pareil",
husked = False,
finished = False,
)
cls.supplier1 = Supplier.objects.create(
company_name = "Acme",
company_location = "Acme Acres",
contact_info = "Call me!"
)
cls.shipment1 = Purchase.objects.create(
tag=9,
shipment_id=9999,
supplier_id = cls.supplier1,
purchase_date='2015-01-09',
purchase_price=9.99,
product_name=cls.variety1,
pieces=99,
kgs=999,
crackout_estimate=99.9
)
cls.shipment2 = Purchase.objects.create(
tag=8,
shipment_id=8888,
supplier_id=cls.supplier1,
purchase_date='2015-01-08',
purchase_price=8.88,
product_name=cls.variety1,
pieces=88,
kgs=888,
crackout_estimate=88.8
)
cls.shipment3 = Purchase.objects.create(
tag=7,
shipment_id=7777,
supplier_id=cls.supplier1,
purchase_date='2014-01-07',
purchase_price=7.77,
product_name=cls.variety1,
pieces=77,
kgs=777,
crackout_estimate=77.7
)
cls.sortrecord1 = SortingRecords.objects.create(
tag=cls.shipment1,
date="2015-02-05",
bags_sorted=20,
turnout=199,
)
cls.sortrecord2 = SortingRecords.objects.create(
tag=cls.shipment1,
date="2015-02-07",
bags_sorted=40,
turnout=399,
)
cls.sortrecord3 = SortingRecords.objects.create(
tag=cls.shipment1,
date='2015-02-09',
bags_sorted=30,
turnout=299,
)
Models
from datetime import datetime
from django.db import models
from django.db.models import Q
class ProductGroup(models.Model):
product_name = models.CharField(max_length=140, primary_key=True)
def __str__(self):
return self.product_name
class Meta:
verbose_name = "Product"
class Supplier(models.Model):
company_name = models.CharField(max_length=45)
company_location = models.CharField(max_length=45)
contact_info = models.CharField(max_length=256)
class Meta:
ordering = ["company_name"]
def __str__(self):
return self.company_name
class Variety(models.Model):
product_group = models.ForeignKey(ProductGroup)
variety_name = models.CharField(max_length=140)
husked = models.BooleanField()
finished = models.BooleanField()
description = models.CharField(max_length=500, blank=True)
class Meta:
ordering = ["product_group_id"]
verbose_name_plural = "Varieties"
def __str__(self):
return self.variety_name
class PurchaseYears(models.Manager):
def purchase_years_list(self):
unique_years = Purchase.objects.dates('purchase_date', 'year')
results_list = []
for p in unique_years:
results_list.append(p.year)
return results_list
class Purchase(models.Model):
tag = models.IntegerField(primary_key=True)
product_name = models.ForeignKey(Variety, related_name='purchases')
shipment_id = models.CharField(max_length=24)
supplier_id = models.ForeignKey(Supplier)
purchase_date = models.DateField()
estimated_delivery = models.DateField(null=True, blank=True)
purchase_price = models.DecimalField(max_digits=6, decimal_places=3)
pieces = models.IntegerField()
kgs = models.IntegerField()
crackout_estimate = models.DecimalField(max_digits=6,decimal_places=3, null=True)
crackout_actual = models.DecimalField(max_digits=6,decimal_places=3, null=True)
objects = models.Manager()
purchase_years = PurchaseYears()
# Keep manager as "objects" in case admin, etc. needs it. Filter can be called like so:
# Purchase.objects.purchase_years_list()
# Managers in docs: https://docs.djangoproject.com/en/1.8/intro/tutorial01/
class Meta:
ordering = ["purchase_date"]
def __str__(self):
return self.shipment_id
def _weight_conversion(self):
return round(self.kgs * 2.20462)
lbs = property(_weight_conversion)
class SortingModelsBagsCalulator(models.Manager):
def total_sorted(self, record_date, current_set):
sorted = [SortingRecords['bags_sorted'] for SortingRecords in current_set if
SortingRecords['date'] <= record_date]
return sum(sorted)
class SortingRecords(models.Model):
tag = models.ForeignKey(Purchase, related_name='sorting_record')
date = models.DateField()
bags_sorted = models.IntegerField()
turnout = models.IntegerField()
objects = models.Manager()
def __str__(self):
return "%s [%s]" % (self.date, self.tag.tag)
class Meta:
ordering = ["date"]
verbose_name_plural = "Sorting Records"
def _calculate_kgs_sorted(self):
kg_per_bag = self.tag.kgs / self.tag.pieces
kgs_sorted = kg_per_bag * self.bags_sorted
return (round(kgs_sorted, 2))
kgs_sorted = property(_calculate_kgs_sorted)
def _byproduct(self):
waste = self.kgs_sorted - self.turnout
return (round(waste, 2))
byproduct = property(_byproduct)
def _bags_remaining(self):
current_set = SortingRecords.objects.values().filter(~Q(id=self.id), tag=self.tag)
sorted = [SortingRecords['bags_sorted'] for SortingRecords in current_set if
SortingRecords['date'] <= self.date]
remaining = self.tag.pieces - sum(sorted) - self.bags_sorted
return remaining
bags_remaining = property(_bags_remaining)
EDIT
It also fails with integers, like so.
django.db.utils.IntegrityError: duplicate key value violates unique constraint "InventoryLogs_purchase_pkey"
DETAIL: Key (tag)=(9) already exists.
UDPATE
So I should have mentioned this earlier, but I completely forgot. I have two unit test files that use the same data. Just for kicks, I matched a primary key in both instances of setUpTestData() to a different value and sure enough, I got the same error.
These two setups were working fine side-by-side before I added more data to one of them. Now, it appears that they need different values. I guess you can only get away with using repeat data for so long.
I continued to get this error without having any duplicate data but I was able to resolve the issue by initializing the object and calling the save() method rather than creating the object via Model.objects.create()
In other words, I did this:
#classmethod
def setUpTestData(cls):
cls.person = Person(first_name="Jane", last_name="Doe")
cls.person.save()
Instead of this:
#classmethod
def setUpTestData(cls):
cls.person = Person.objects.create(first_name="Jane", last_name="Doe")
I've been running into this issue sporadically for months now. I believe I just figured out the root cause and a couple solutions.
Summary
For whatever reason, it seems like the Django test case base classes aren't removing the database records created by let's just call it TestCase1 before running TestCase2. Which, in TestCase2 when it tries to create records in the database using the same IDs as TestCase1 the database raises a DuplicateKey exception because those IDs already exists in the database. And even saying the magic word "please" won't help with database duplicate key errors.
Good news is, there are multiple ways to solve this problem! Here are a couple...
Solution 1
Make sure if you are overriding the class method tearDownClass that you call super().tearDownClass(). If you override tearDownClass() without calling its super, it will in turn never call TransactionTestCase._post_teardown() nor TransactionTestCase._fixture_teardown(). Quoting from the doc string in TransactionTestCase._post_teardown()`:
def _post_teardown(self):
"""
Perform post-test things:
* Flush the contents of the database to leave a clean slate. If the
class has an 'available_apps' attribute, don't fire post_migrate.
* Force-close the connection so the next test gets a clean cursor.
"""
If TestCase.tearDownClass() is not called via super() then the database is not reset in between test cases and you will get the dreaded duplicate key exception.
Solution 2
Override TransactionTestCase and set the class variable serialized_rollback = True, like this:
class MyTestCase(TransactionTestCase):
fixtures = ['test-data.json']
serialized_rollback = True
def test_name_goes_here(self):
pass
Quoting from the source:
class TransactionTestCase(SimpleTestCase):
...
# If transactions aren't available, Django will serialize the database
# contents into a fixture during setup and flush and reload them
# during teardown (as flush does not restore data from migrations).
# This can be slow; this flag allows enabling on a per-case basis.
serialized_rollback = False
When serialized_rollback is set to True, Django test runner rolls back any transactions inserted into the database beween test cases. And batta bing, batta bang... no more duplicate key errors!
Conclusion
There are probably many more ways to implement a solution for the OP's issue, but these two should work nicely. Would definitely love to have more solutions added by others for clarity sake and a deeper understanding of the underlying Django test case base classes. Phew, say that last line real fast three times and you could win a pony!
The log you provided states DETAIL: Key (product_name)=(Almonds) already exists. Did you verify in your db?
To prevent such errors in the future, you should prefix all your test data string by test_
I discovered the issue, as noted at the bottom of the question.
From what I can tell, the database didn't like me using duplicate data in the setUpTestData() methods of two different tests. Changing the primary key values in the second test corrected the problem.
I think the problem here is that you had a tearDownClass method in your TestCase without the call to super method.
In this way the django TestCase lost the transactional functionalities behind the setUpTestData so it doesn't clean your test db after a TestCase is finished.
Check warning in django docs here:
https://docs.djangoproject.com/en/1.10/topics/testing/tools/#django.test.SimpleTestCase.allow_database_queries
I had similar problem that had been caused by providing the primary key value to a test case explicitly.
As discussed in the Django documentation, manually assigning a value to an auto-incrementing field doesn’t update the field’s sequence, which might later cause a conflict.
I have solved it by altering the sequence manually:
from django.db import connection
class MyTestCase(TestCase):
#classmethod
def setUpTestData(cls):
Model.objects.create(id=1)
with connection.cursor() as c:
c.execute(
"""
ALTER SEQUENCE "app_model_id_seq" RESTART WITH 2;
"""
)