Knower
Creating dummy data

Creating Dummy Data

Introduction

I was trying to figure out way to create bunch of dummy data for testing that can be done automatically instead of manually.

Solution

I ended up finding out django-seed (opens in a new tab) package that allows me to create dummy data as much as I want. I referred to How to create custom django-admin commands (opens in a new tab) and tried to create custom command with using that package.

Process

Installing Package

Install django-seed package.


pip install django-seed

Configuring INSTALLED_APPS

Install (opens in a new tab) package in INSTALLED_APPS of settings.py.


# settings.py
INSTALLED_APPS = [
# ...
"django_seed",
# ...
]

Create File

Create file for custom command creating user dummy data. I followed exactly what Django suggested (opens in a new tab).

      • __init__.py
        • __init__.py
        • fake_users.py

    • Creating Custom Command Class

    Create Command class inherited from BaseCommand (opens in a new tab).

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    class Command(BaseCommand):
    pass

    django_seed Initialization

    Initialize seeder Provider in order to utilize django-seed pacakge.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    seeder = Seed.seeder()
    class Command(BaseCommand):
    pass

    Help Text

    I used help (opens in a new tab) attribute for adding help text of command.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    seeder = Seed.seeder()
    class Command(BaseCommand):
    help = "Creating fake user data"

    Designating Command Argument

    I designated argument that can be passed to my custom command with using add_arguments() (opens in a new tab) method. I created argument called --number and set its default value as 1.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    seeder = Seed.seeder()
    class Command(BaseCommand):
    help = "Creating fake user data"
    def add_arguments(self, parser):
    parser.add_argument(
    "--number", default=1, help="How many users do you want to create"
    )

    Command Logic

    Create command logic with using handle() (opens in a new tab) method. First, bring --number argument that is passed to our custom command.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    seeder = Seed.seeder()
    class Command(BaseCommand):
    help = "Creating fake user data"
    def add_arguments(self, parser):
    parser.add_argument(
    "--number", default=1, help="How many users do you want to create"
    )
    def handle(self, *args, **kwargs):
    number = kwargs.get("number")

    Seeder Configuration

    After importing User model set in models.py, I specified which values should be filled in each field1.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    from users.models import User
    seeder = Seed.seeder()
    class Command(BaseCommand):
    help = "Creating fake user data"
    def add_arguments(self, parser):
    parser.add_argument(
    "--number", default=1, help="How many users do you want to create"
    )
    def handle(self, *args, **kwargs):
    number = kwargs.get("number")
    seeder.add_entity(
    User,
    number,
    {
    "email": lambda x: seeder.faker.email(),
    "phone_number": lambda x: seeder.faker.phone_number(),
    "is_staff": False,
    "is_active": True,
    },
    )
    seeder.execute()

    Editing Success Message

    Lastly, I customized style of success syntax message with using style (opens in a new tab) property. I passed number argument value with using f-string.

    fake_users.py
    Copy

    from django.core.management.base import BaseCommand
    from django_seed import Seed
    from users.models import User
    seeder = Seed.seeder()
    class Command(BaseCommand):
    help = "Creating fake user data"
    def add_arguments(self, parser):
    parser.add_argument(
    "--number", default=1, help="How many users do you want to create"
    )
    def handle(self, *args, **kwargs):
    number = kwargs.get("number")
    seeder.add_entity(
    User,
    number,
    {
    "email": lambda x: seeder.faker.email(),
    "phone_number": lambda x: seeder.faker.phone_number(),
    "is_staff": False,
    "is_active": True,
    },
    )
    seeder.execute()
    self.stdout.write(self.style.SUCCES(f"{number} fake users created!"))

    Creating Custom Command Class

    Create Command class inherited from BaseCommand (opens in a new tab).

    django_seed Initialization

    Initialize seeder Provider in order to utilize django-seed pacakge.

    Help Text

    I used help (opens in a new tab) attribute for adding help text of command.

    Designating Command Argument

    I designated argument that can be passed to my custom command with using add_arguments() (opens in a new tab) method. I created argument called --number and set its default value as 1.

    Command Logic

    Create command logic with using handle() (opens in a new tab) method. First, bring --number argument that is passed to our custom command.

    Seeder Configuration

    After importing User model set in models.py, I specified which values should be filled in each field1.

    Editing Success Message

    Lastly, I customized style of success syntax message with using style (opens in a new tab) property. I passed number argument value with using f-string.

    fake_users.py
    CopyExpandClose

    from django.core.management.base import BaseCommand
    class Command(BaseCommand):
    pass

    Result

    It works like a charm as shown in image below.

    result

    Debugging

    TypeError: make_aware() got an unexpected keyword argument 'is_dst'

    Problem

    I tried to seed fake dummy data with using following command line in terminal using django-seed package.


    python manage.py seed users --number=10

    But then I got the following error.


    Traceback (most recent call last):
    File "/Users/apensia/dev/knower-admin/manage.py", line 32, in <module>
    main()
    File "/Users/apensia/dev/knower-admin/manage.py", line 28, in main
    execute_from_command_line(sys.argv)
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django/core/management/__init__.py", line 442, in execute_from_command_line
    utility.execute()
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django/core/management/__init__.py", line 436, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django/core/management/base.py", line 413, in run_from_argv
    self.execute(*args, **cmd_options)
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django/core/management/base.py", line 459, in execute
    output = self.handle(*args, **options)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django/core/management/base.py", line 646, in handle
    app_output = self.handle_app_config(app_config, **options)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/management/commands/seed.py", line 63, in handle_app_config
    generated = seeder.execute()
    ^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/seeder.py", line 250, in execute
    executed_entity = entity.execute(using, inserted_entities)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/seeder.py", line 157, in execute
    faker_data = {
    ^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/seeder.py", line 158, in <dictcomp>
    field: format_field(field_format, inserted_entities)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/seeder.py", line 144, in format_field
    return format(inserted_entities)
    ^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/guessers.py", line 120, in <lambda>
    return lambda x: _timezone_format(faker.date_time())
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/apensia/dev/knower-admin/venv/lib/python3.11/site-packages/django_seed/guessers.py", line 21, in _timezone_format
    return timezone.make_aware(value, timezone.get_current_timezone(), is_dst=False)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    TypeError: make_aware() got an unexpected keyword argument 'is_dst'

    Analysis

    While spectating issues created in django-seed Github repositories, other developers also experienced same error while creating DateTime data in Django version 5 or more. This is because Django version 5 or later does not accept is_dst as an argument anymore.

    Solution

    According to salimbyte's suggestion, (opens in a new tab), I solved the problem by setting USE_TZ (opens in a new tab) value as False.


    # settings.py
    USE_TZ = False

    Footnotes

    1. Using with code (opens in a new tab) ↩

    Creating custom validator for model fieldDjango meeting gulp