Setting Up Your First Django Project and App

1. Projects vs. Apps: The Django Philosophy

Before we write any code, it's important to understand Django's core organizational concept: the distinction between a project and an app.

• A Project is the entire web application. It holds the configuration, settings, and URL mappings that apply to the whole site. Think of it as the house that contains everything.
• An App is a self-contained module within the project that provides a specific piece of functionality. For example, a project might have separate apps for user authentication, a blog, and a payment system. Think of an app as a specific room in the house, like the kitchen or the bedroom.

Our goal today is to build the "house" (the Django project) and then create the first "room" (a Django app that will eventually manage our tasks).

For a quick conceptual overview, let's hear this distinction explained by Programming with Mosh.

2. Step 1: Preparing Your Development Environment

Every professional Python project starts with a clean, isolated environment. This prevents dependencies from one project from conflicting with another. We'll use Python's built-in venv module for this.

The following reading provides a clear, step-by-step guide to setting up this environment and installing Django.

To summarize the key commands from that reading (assuming a macOS/Linux terminal):

1. mkdir task_manager && cd task_manager - Create and enter your project directory.
2. python3 -m venv venv - Create the virtual environment.
3. source venv/bin/activate - Activate it. You'll see (venv) in your prompt.
4. pip install django - Install the Django framework.
5. pip freeze > requirements.txt - Save your project's dependencies to a file. This is crucial for collaboration and deployment.

3. Step 2: Creating the Django Project

With Django installed, you can now generate the project boilerplate. We will use a single, concise video to walk through the main commands for creating both the project and the first app.

Watch the following video to see how to create the project structure.

Let's do this for our own project. In your terminal (inside the task_manager folder with the virtual environment activated), run the following command:

# We'll name our project configuration 'config'
django-admin startproject config .

The . is important; it tells Django to create the files in the current directory (task_manager) rather than creating an extra, unnecessary parent folder. Your folder structure should now look like this:

task_manager/
├── venv/
├── config/
│   ├── __init__.py
│   ├── asgi.py
│   ├── settings.py
│   ├── urls.py
│   └── wsgi.py
└── manage.py

• manage.py: Your command-line utility for interacting with your Django project. You'll use this for almost everything, from running the server to creating apps.
• config/: The package containing your project's configuration.
  • settings.py: Contains all your project's settings, like database configuration, installed apps, and more.
  • urls.py: The "table of contents" for your site, mapping URL patterns to their corresponding logic.

4. Step 3: Creating Your First Django App

Now that we have the project "house," let's create the "room" that will handle our tasks. We'll call this app tasks.

Let's continue with the same video to see this in action.

Run the command in your terminal:

python3 manage.py startapp tasks

This creates a new folder named tasks with its own set of files. Your project structure now looks like this:

The key files in the tasks app folder are:

• models.py: Where you will define your database structure (e.g., a Task table with columns for title, description, and due_date).
• views.py: Where you'll write the logic to handle web requests and define what the user sees.
• admin.py: For configuring how your models appear in Django's built-in admin interface.

5. Step 4: Registering the App and Verifying the Setup

You've created the app, but the Django project doesn't automatically know it exists. You must "register" it.

1. Register the App: Open config/settings.py. Find the INSTALLED_APPS list and add your new app. It's best practice to add the app's configuration class, which lives in tasks/apps.py.

   # config/settings.py
   
   INSTALLED_APPS = [
       'django.contrib.admin',
       'django.contrib.auth',
       'django.contrib.contenttypes',
       'django.contrib.sessions',
       'django.contrib.messages',
       'django.contrib.staticfiles',
   
       # My Apps
       'tasks.apps.TasksConfig', # Add this line
   ]
   

2. Run Initial Migrations: Django comes with built-in apps (like auth and admin) that need database tables. Let's create them. This process is called running migrations.

   python3 manage.py migrate
   

3. Run the Development Server: Finally, let's make sure everything works by starting the development server.

   python3 manage.py runserver
   

Now, open a web browser and go to http://127.0.0.1:8000/. You should see a "The install worked successfully! Congratulations!" page. This confirms your project is set up correctly!

Conclusion

Congratulations, you have successfully set up a Django project! This is a significant first step. You now have a working skeleton for your web application and understand how Django organizes code into projects and apps.

Key Takeaways:

• A Django project is the main container for your web application's settings and configurations.
• A Django app is a smaller, modular component that handles a specific feature.
• Key commands for setup are:
  • django-admin startproject <project_name> .
  • python3 manage.py startapp <app_name>
• New apps must be registered in the INSTALLED_APPS list in settings.py.
• python3 manage.py runserver starts a development server to let you test your site locally.

Preview of the Next Lesson:
Our site is running, but it doesn't do anything yet. In our next lesson, we will bring it to life. We will learn how to configure URL patterns to route requests to views. You'll write your first view—a Python function that takes a web request and returns a web response—and create your very first custom webpage.