Writing your first Django app, part 1 | Django documentation (2024)

/

$ python -m django --version

...\> py -m django --version

Where to get help:

If you’re having trouble going through this tutorial, please head over tothe Getting Help section of the FAQ.

Creating a project¶

If this is your first time using Django, you’ll have to take care of someinitial setup. Namely, you’ll need to auto-generate some code that establishes aDjango project – a collection of settings for an instance of Django,including database configuration, Django-specific options andapplication-specific settings.

From the command line, cd into a directory where you’d like to store yourcode, then run the following command:

$ django-admin startproject mysite

...\> django-admin startproject mysite

This will create a mysite directory in your current directory. If it didn’twork, see Problems running django-admin.

Let’s look at what startproject created:

mysite/ manage.py mysite/ __init__.py settings.py urls.py asgi.py wsgi.py

These files are:

• The outer mysite/ root directory is a container for your project. Itsname doesn’t matter to Django; you can rename it to anything you like.
• manage.py: A command-line utility that lets you interact with thisDjango project in various ways. You can read all the details aboutmanage.py in django-admin and manage.py.
• The inner mysite/ directory is the actual Python package for yourproject. Its name is the Python package name you’ll need to use to importanything inside it (e.g. mysite.urls).
• mysite/__init__.py: An empty file that tells Python that thisdirectory should be considered a Python package. If you’re a Python beginner,read more about packages in the official Python docs.
• mysite/settings.py: Settings/configuration for this Djangoproject. Django settings will tell you all about how settingswork.
• mysite/urls.py: The URL declarations for this Django project; a“table of contents” of your Django-powered site. You can read more aboutURLs in URL dispatcher.
• mysite/asgi.py: An entry-point for ASGI-compatible web servers toserve your project. See How to deploy with ASGI for more details.
• mysite/wsgi.py: An entry-point for WSGI-compatible web servers toserve your project. See How to deploy with WSGI for more details.

The development server¶

Let’s verify your Django project works. Change into the outer mysite directory, ifyou haven’t already, and run the following commands:

$ python manage.py runserver

...\> py manage.py runserver

You’ll see the following output on the command line:

Performing system checks...System check identified no issues (0 silenced).You have unapplied migrations; your app may not work properly until they are applied.Run 'python manage.py migrate' to apply them.August 08, 2024 - 15:50:53Django version 5.1, using settings 'mysite.settings'Starting development server at http://127.0.0.1:8000/Quit the server with CONTROL-C.

Now that the server’s running, visit http://127.0.0.1:8000/ with your webbrowser. You’ll see a “Congratulations!” page, with a rocket taking off.It worked!

You’ve started the Django development server, a lightweight web server writtenpurely in Python. We’ve included this with Django so you can develop thingsrapidly, without having to deal with configuring a production server – such asApache – until you’re ready for production.

Now’s a good time to note: don’t use this server in anything resembling aproduction environment. It’s intended only for use while developing. (We’re inthe business of making web frameworks, not web servers.)

(To serve the site on a different port, see the runserver reference.)

Creating the Polls app¶

Now that your environment – a “project” – is set up, you’re set to startdoing work.

Each application you write in Django consists of a Python package that followsa certain convention. Django comes with a utility that automatically generatesthe basic directory structure of an app, so you can focus on writing coderather than creating directories.

Your apps can live anywhere on your Python path. Inthis tutorial, we’ll create our poll app in the same directory as yourmanage.py file so that it can be imported as its own top-level module,rather than a submodule of mysite.

To create your app, make sure you’re in the same directory as manage.pyand type this command:

$ python manage.py startapp polls

...\> py manage.py startapp polls

That’ll create a directory polls, which is laid out like this:

polls/ __init__.py admin.py apps.py migrations/ __init__.py models.py tests.py views.py

This directory structure will house the poll application.

Write your first view¶

Let’s write the first view. Open the file polls/views.pyand put the following Python code in it:

from django.http import HttpResponsedef index(request): return HttpResponse("Hello, world. You're at the polls index.")

This is the most basic view possible in Django. To access it in a browser, weneed to map it to a URL - and for this we need to define a URL configuration,or “URLconf” for short. These URL configurations are defined inside eachDjango app, and they are Python files named urls.py.

To define a URLconf for the polls app, create a file polls/urls.pywith the following content:

from django.urls import pathfrom . import viewsurlpatterns = [ path("", views.index, name="index"),]

Your app directory should now look like:

polls/ __init__.py admin.py apps.py migrations/ __init__.py models.py tests.py urls.py views.py

The next step is to configure the global URLconf in the mysite project toinclude the URLconf defined in polls.urls. To do this, add an import fordjango.urls.include in mysite/urls.py and insert aninclude() in the urlpatterns list, so you have:

from django.contrib import adminfrom django.urls import include, pathurlpatterns = [ path("polls/", include("polls.urls")), path("admin/", admin.site.urls),]

The include() function allows referencing other URLconfs.Whenever Django encounters include(), it chops off whateverpart of the URL matched up to that point and sends the remaining string to theincluded URLconf for further processing.

The idea behind include() is to make it easy toplug-and-play URLs. Since polls are in their own URLconf(polls/urls.py), they can be placed under “/polls/”, or under“/fun_polls/”, or under “/content/polls/”, or any other path root, and theapp will still work.

You have now wired an index view into the URLconf. Verify it’s working withthe following command:

$ python manage.py runserver

...\> py manage.py runserver

Go to http://localhost:8000/polls/ in your browser, and you should see thetext “Hello, world. You’re at the polls index.”, which you defined in theindex view.

The path() function is passed four arguments, two required:route and view, and two optional: kwargs, and name.At this point, it’s worth reviewing what these arguments are for.