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‎docs/technologies/django/custom-commands.mdx‎

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---
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title : Django Custom Commands
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sidebar_label : Custom Commands
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---
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# Django Custom Commands
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<SubHeading>Learn how to add our own commands in Django Framework</SubHeading>
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This article explains how to **write our own Django custom commands** that might help us to test, upload data or extract valuable information in a production environment from a Django project.
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For newcomers, [Django](https://www.djangoproject.com/) is a popular web framework designed and written in Python by experienced developers.
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The main advantage of a custom command is that all Django machinery is loaded and ready to be used.
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That means you can import models, execute queries to the database using Django’s ORM and interact with all your project’s resources.
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![Django Releases - Tutorial provided by AppSeed.](https://user-images.githubusercontent.com/51070104/268675023-54ea4ace-a8ad-442b-9b43-2ba12a6403ba.jpg)
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> Topics
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- Create a new Django App and Update Django to use it
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- Visualize the required directory structure inside the app
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- Code end execute a few custom commands:
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- `cmd_time.py` - show current timestamp
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- `cmd_apps` - list all registered apps
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- `cmd_models` - list all apps and associated models
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- `cmd_showcfg` - list all CFG keys and values
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- The [source code](https://github.com/app-generator/django-learn-by-coding) can be found on Github (MIT License)
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## ✅ Create a new Django App
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This tutorial assumes that we have a working Django project and we will move forward and create a new app via startapp subcommand:
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```bash
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$ python manage.py startapp app_customcmd
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```
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Inside the new app directory, we need to create a directory structure as shown below:
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```bash
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< PROJECT ROOT > <-- project directory
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|
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|-- app_customcmd/ <-- app directory
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| |-- management/
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| | +-- __init__.py
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| | +-- commands/
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| | +-- __init__.py
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| | +-- cmd_....py <-- module where all commands are saved
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```
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Once we have built and configure Django to use the new app, all commands defined in commands directory are automatically discovered even without an application restart.
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## ✅ Configure Django
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To execute our custom commands we need to activate app_customcmd in the project configuration:
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```python
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INSTALLED_APPS = [
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'django.contrib.admin',
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'django.contrib.auth',
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'django.contrib.contenttypes',
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'django.contrib.sessions',
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'django.contrib.messages',
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'django.contrib.staticfiles',
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'app_customcmd', # <-- NEW
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]
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```
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## ✅ Custom Commands
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This section presents for custom commands that will access and report a few things related to a Django project internals - Let's go!
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### Show Current Time
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This simple custom command help us to accommodate with the concept. Here is the code, saved in the `app_customcmd/management/commands` directory:
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```python
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from django.core.management.base import BaseCommand
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from django.utils import timezone
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class Command(BaseCommand):
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help = 'Displays current time'
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def handle(self, *args, **kwargs):
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time = timezone.now().strftime('%X')
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self.stdout.write("It's %s" % time)
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```
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The actual executed code resides in the handle method and the execution should display something similar to this:
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```bash
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$ python manage.py cmd_time
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It 09:18:08 <-- The output from our custom CMD
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```
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The most important aspect regarding the code is the usage of BaseCommand as a super-class for our definition.
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### Show Registered Apps
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This sample will iterate over all registered and active apps and print their names.
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```python
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from django.core.management.base import BaseCommand
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from django.apps import apps
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class Command(BaseCommand):
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help = 'Displays registered apps'
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def handle(self, *args, **kwargs):
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for app in apps.get_app_configs():
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self.stdout.write(" APP -> %s" % app.verbose_name)
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```
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> **Script execution and output**
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```bash
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$ python manage.py cmd_apps
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APP -> Administration # Default Django App
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APP -> Authentication and Authorization # Default Django App
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APP -> Content Types # Default Django App
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APP -> Sessions # Default Django App
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APP -> Messages # Default Django App
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APP -> Static Files # Default Django App
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APP -> App_Customcmd # <-- Our NEW App
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```
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### Show models for each app
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This command is quite similar with the previous one, but provide also the registered models for each app.
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```python
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from django.core.management.base import BaseCommand
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from django.apps import apps
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class Command(BaseCommand):
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help = 'Displays registered apps and models'
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def handle(self, *args, **kwargs):
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# Iterate over apps
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for app in apps.get_app_configs():
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self.stdout.write(" APP -> %s" % app.verbose_name)
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# Iterate over models # <-- New Code
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for model in app.get_models(): # <-- New Code
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self.stdout.write("\t |- (model) -> %s" % model) # <-- New Code
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```
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> **The execution and output**
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```bash
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$ python manage.py cmd_models
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APP -> Administration
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|- (model) -> <class 'django.contrib.admin.models.LogEntry'>
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APP -> Authentication and Authorization
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|- (model) -> <class 'django.contrib.auth.models.Permission'>
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|- (model) -> <class 'django.contrib.auth.models.Group'>
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|- (model) -> <class 'django.contrib.auth.models.User'>
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APP -> Content Types
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|- (model) -> <class 'django.contrib.contenttypes.models.ContentType'>
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APP -> Sessions
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|- (model) -> <class 'django.contrib.sessions.models.Session'>
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APP -> Messages
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APP -> Static Files
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APP -> App_Forms
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APP -> App_Pdf
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APP -> App_Customcmd
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APP -> App
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|- (model) -> <class 'app.models.Book'>
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```
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### Print Config Variables
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This custom command scan the settings object for proprieties and print all values.
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```python
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from django.core.management.base import BaseCommand
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from django.utils import timezone
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from django.conf import settings
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class Command(BaseCommand):
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help = 'Displays project config'
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def handle(self, *args, **kwargs):
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# type( settings ) => <class 'django.conf.LazySettings'>
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# settings.__dict__
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# Iterate over apps
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for key in settings.__dict__.keys():
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self.stdout.write(" Cfg Key: " + key + " -> %s" % settings.__dict__[ key ] )
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```
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> **The output and execution**
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```bash
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(env) PS D:\work\repo-samples\django-learn-by-coding> python manage.py cmd_showcfg
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Cfg Key: _wrapped -> <Settings "config.settings">
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Cfg Key: INSTALLED_APPS -> ['django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', 'app_forms', 'app_pdf', 'app_customcmd', 'app']
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Cfg Key: DEBUG -> True
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Cfg Key: LOGGING_CONFIG -> logging.config.dictConfig
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Cfg Key: LOGGING -> {}
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Cfg Key: DEFAULT_EXCEPTION_REPORTER -> django.views.debug.ExceptionReporter
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Cfg Key: FORCE_SCRIPT_NAME -> None
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Cfg Key: DEFAULT_TABLESPACE ->
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Cfg Key: DEFAULT_AUTO_FIELD -> django.db.models.BigAutoField
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Cfg Key: ABSOLUTE_URL_OVERRIDES -> {}
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Cfg Key: AUTH_USER_MODEL -> auth.User
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Cfg Key: DATABASES -> {'default': {'ENGINE': 'django.db.backends.sqlite3', 'NAME': WindowsPath('D:/work/repo-samples/django-learn-by-coding/db.sqlite3'), 'ATOMIC_REQUESTS': False, 'AUTOCOMMIT': True, 'CONN_MAX_AGE': 0, 'OPTIONS': {}, 'TIME_ZONE': None, 'USER': '', 'PASSWORD': '', 'HOST': '', 'PORT': '', 'TEST': {'CHARSET': None, 'COLLATION': None, 'MIGRATE': True, 'MIRROR': None, 'NAME': None}}}
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...
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(truncated output)
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```
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## ✅ In Summary
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Writing custom commands in our Django projects might help us to extract stats, execute cron jobs, and check the health of a project that runs in production.
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## ✅ Resources
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- 👉 Access [AppSeed](https://appseed.us/) and start your next project
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- 👉 [Deploy Projects on Aws, Azure and Digital Ocean](https://www.docs.deploypro.dev/) via **DeployPRO**
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- 👉 Create an amazing landing page with [Simpllo, an open-source site builder](https://www.simpllo.com/)
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- 👉 [Django App Generator](https://app-generator.dev/django/) - A 2nd generation App Builder

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