An easy-to-use implementation of Creation Methods (aka Object Factory) for Django, backed by Faker.

django_fakery will try to guess the field's value based on the field's name and type.

Install with:

$ pip install django-fakery

from django_fakery import factory
from myapp.models import MyModel

factory.m(MyModel)(field='value')

If you're having issues with circular imports, you can also reference a model by using the M utility function:

from django_fakery import factory, M

factory.m(M("myapp.MyModel"))(field="value")

If you really don't want to import things, you could also just reference a model by using the <app_label>.<ModelName> syntax. This is not encouraged, as it will likely break type-hinting:

from django_fakery import factory

factory.m("myapp.MyModel")(field="value")

If you use pytest, you can use the fakery and fakery_shortcuts` fixtures (requirespytestandpytest-django): .. code-block:: python import pytest from myapp.models import MyModel @pytest.mark.django_db def test_mymodel(fakery, fakery_shortcuts): fakery.m(MyModel)(field=fakery_shortcuts.future_datetime()) If you'd rather, you can use a more wordy API: .. code-block:: python from django_fakery import factory from myapp.models import MyModel factory.make( MyModel, fields={ 'field': 'value', } ) We will use the short API thorough the documentation. The value of a field can be any python object, a callable, or a lambda: .. code-block:: python from django.utils import timezone from django_fakery import factory from myapp.models import MyModel factory.m(MyModel)(created=timezone.now) When using a lambda, it will receive two arguments:nis the iteration number, andfis an instance offaker: .. code-block:: python from django.contrib.auth.models import User user = factory.m(User)( username=lambda n, f: 'user_{}'.format(n), )django-fakeryincludes some pre-built lambdas for common needs. See shortcuts_ for more info. You can create multiple objects by using thequantityparameter: .. code-block:: python from django_fakery import factory from django.contrib.auth.models import User factory.m(User, quantity=4) For convenience, when the value of a field is a string, it will be interpolated with the iteration number: .. code-block:: python from myapp.models import MyModel user = factory.m(User, quantity=4)( username='user_{}', ) Custom fields ------------- You can add support for custom fields by adding your custom field class and a function infactory.field_types: .. code-block:: python from django_fakery import factory from my_fields import CustomField def func(faker, field, count, *args, **kwargs): return 43 factory.field_types.add( CustomField, (func, [], {}) ) As a shortcut, you can specified any Faker function by its name: .. code-block:: python from django_fakery import factory from my_fields import CustomField factory.field_types.add( CustomField, ("random_int", [], {"min": 0, "max": 60}) ) Foreign keys ------------ Non-nullableForeignKeys create related objects automatically. If you want to explicitly create a related object, you can pass a factory like any other value: .. code-block:: python from django.contrib.auth.models import User from food.models import Pizza pizza = factory.m(Pizza)( chef=factory.m(User)(username='Gusteau'), ) If you'd rather not create related objects and reuse the same value for a foreign key, you can use the special valuedjango_fakery.rels.SELECT: .. code-block:: python from django_fakery import factory, rels from food.models import Pizza pizza = factory.m(Pizza, quantity=5)( chef=rels.SELECT, )django-fakerywill always use the first instance of the related model, creating one if necessary. ManyToManies ------------ BecauseManyToManyFields are implicitly nullable (ie: they're always allowed to have their.count()equal to0), related objects on those fields are not automatically created for you. If you want to explicitly create a related objects, you can pass a list as the field's value: .. code-block:: python from food.models import Pizza, Topping pizza = factory.m(Pizza)( toppings=[ factory.m(Topping)(name='Anchovies') ], ) You can also pass a factory, to create multiple objects: .. code-block:: python from food.models import Pizza, Topping pizza = factory.m(Pizza)( toppings=factory.m(Topping, quantity=5), ) .. _shortcuts: Shortcuts ---------django-fakeryincludes some shortcut functions to generate commonly needed values.future_datetime(end='+30d')~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Returns adatetimeobject in the future (that is, 1 second from now) up to the specifiedend.endcan be a string, anotther datetime, or a timedelta. If it's a string, it must start with `+`, followed by and integer and a unit, Eg:'+30d'. Defaults to'+30d'Valid units are: *'years','y'*'weeks','w'*'days','d'*'hours','hours'*'minutes','m'*'seconds','s'Example: .. code-block:: python from django_fakery import factory, shortcuts from myapp.models import MyModel factory.m(MyModel)(field=shortcuts.future_datetime('+1w'))future_date(end='+30d')~~~~~~~~~~~~~~~~~~~~~~~~~~~ Returns adateobject in the future (that is, 1 day from now) up to the specifiedend.endcan be a string, another date, or a timedelta. If it's a string, it must start with `+`, followed by and integer and a unit, Eg:'+30d'. Defaults to'+30d'past_datetime(start='-30d')~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Returns adatetimeobject in the past between 1 second ago and the specifiedstart.startcan be a string, another datetime, or a timedelta. If it's a string, it must start with `-`, followed by and integer and a unit, Eg:'-30d'. Defaults to'-30d'past_date(start='-30d')~~~~~~~~~~~~~~~~~~~~~~~~~~~ Returns adateobject in the past between 1 day ago and the specifiedstart.startcan be a string, another date, or a timedelta. If it's a string, it must start with `-`, followed by and integer and a unit, Eg:'-30d'. Defaults to'-30d'Lazies ------ You can refer to the created instance's own attributes or method by using `Lazy` objects. For example, if you'd like to create user with email as username, and have them always match, you could do: .. code-block:: python from django_fakery import factory, Lazy from django.contrib.auth.models import User factory.m(auth.User)( username=Lazy('email'), ) If you want to assign a value returned by a method on the instance, you can pass the method's arguments to theLazyobject: .. code-block:: python from django_fakery import factory, Lazy from myapp.models import MyModel factory.m(MyModel)( myfield=Lazy('model_method', 'argument', keyword='keyword value'), ) Pre-save and Post-save hooks ---------------------------- You can define functions to be called right before the instance is saved or right after: .. code-block:: python from django.contrib.auth.models import User from django_fakery import factory factory.m( User, pre_save=[ lambda u: u.set_password('password') ], )(username='username') Since settings a user's password is such a common case, we special-cased that scenario, so you can just pass it as a field: .. code-block:: python from django.contrib.auth.models import User from django_fakery import factory factory.m(User)( username='username', password='password', ) Get or Make ----------- You can check for existance of a model instance and create it if necessary by using theg_m(short forget_or_make) method: .. code-block:: python from myapp.models import MyModel myinstance, created = factory.g_m( MyModel, lookup={ 'myfield': 'myvalue', } )(myotherfield='somevalue') If you're looking for a more explicit API, you can use the.get_or_make()method: .. code-block:: python from myapp.models import MyModel myinstance, created = factory.get_or_make( MyModel, lookup={ 'myfield': 'myvalue', }, fields={ 'myotherfield': 'somevalue', }, ) Get or Update ------------- You can check for existence of a model instance and update it by using theg_u(short forget_or_update) method: .. code-block:: python from myapp.models import MyModel myinstance, created = factory.g_u( MyModel, lookup={ 'myfield': 'myvalue', } )(myotherfield='somevalue') If you're looking for a more explicit API, you can use the.get_or_update()method: .. code-block:: python from myapp.models import MyModel myinstance, created = factory.get_or_update( MyModel, lookup={ 'myfield': 'myvalue', }, fields={ 'myotherfield': 'somevalue', }, ) Non-persistent instances ------------------------ You can build instances that are not saved to the database by using the.b()method, just like you'd use.m(): .. code-block:: python from django_fakery import factory from myapp.models import MyModel factory.b(MyModel)( field='value', ) Note that since the instance is not saved to the database,.build()does not support ManyToManies or post-save hooks. If you're looking for a more explicit API, you can use the.build()`` method:

from django_fakery import factory
from myapp.models import MyModel

factory.build(
    MyModel,
    fields={
        'field': 'value',
    }
)

Use a blueprint:

from django.contrib.auth.models import User
from django_fakery import factory

user = factory.blueprint(User)

user.make(quantity=10)

Blueprints can refer other blueprints:

from food.models import Pizza

pizza = factory.blueprint(Pizza).fields(
        chef=user,
    )
)

You can also override the field values you previously specified:

from food.models import Pizza

pizza = factory.blueprint(Pizza).fields(
        chef=user,
        thickness=1
    )
)

pizza.m(quantity=10)(thickness=2)

Or, if you'd rather use the explicit api:

from food.models import Pizza

pizza = factory.blueprint(Pizza).fields(
        chef=user,
        thickness=1
    )
)

thicker_pizza = pizza.fields(thickness=2)
thicker_pizza.make(quantity=10)

from django.contrib.auth.models import User
from django_fakery import factory

factory.m(User, seed=1234, quantity=4)(
    username='regularuser_{}'
)

The API is heavily inspired by model_mommy.

This software is released under the MIT License.