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PotatoScript edited this page Mar 2, 2025 · 17 revisions

🚀 Django Framework – Full Step-by-Step Guide 🎯

Django is a high-level Python web framework that lets you build powerful and scalable web applications quickly. It follows the Model-View-Template (MVT) architecture and includes built-in tools for authentication, database management, and security.

📌 1. Installing Django

To install Django, ensure Python and pip are installed.

✅ Step 1: Check Python & pip Versions

Open a terminal and type:

python --version
pip --version

✔ If Python 3.x is installed, you're ready to proceed.

✅ Step 2: Install Django

Run:

pip install django

✔ This installs the latest Django version.

✅ Step 3: Verify Django Installation

django-admin --version

✔ If you see a version number, Django is installed successfully! 🎉

📌 2. Creating a Django Project

A Django project is a collection of settings and configurations for a web application.

✅ Step 1: Create a New Project

django-admin startproject myproject

✔ This creates a myproject folder with Django settings.

✅ Step 2: Navigate to the Project Folder

cd myproject

✅ Step 3: Run the Development Server

python manage.py runserver

✔ Open http://127.0.0.1:8000/ in your browser.
✔ If you see "Congratulations! It worked!", Django is running! 🎯

📌 3. Django Project Structure

After running startproject, Django creates these files:

myproject/
│── manage.py         # Command-line tool for Django
│── myproject/        # Main project directory
│   │── settings.py   # Configuration file
│   │── urls.py       # URL routing
│   │── wsgi.py       # Web server gateway
│   │── asgi.py       # ASGI server file

📌 4. Creating a Django App

A Django app is a modular component of a project.

✅ Step 1: Create an App

python manage.py startapp myapp

✔ This creates a folder myapp/ for the app.

✅ Step 2: Add the App to Django Settings

Open settings.py and add "myapp" inside INSTALLED_APPS:

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'myapp',  # Add your app here
]

📌 5. Creating a View

A view handles requests and returns a response.

✅ Step 1: Define a View

Open myapp/views.py and add:

from django.http import HttpResponse

def home(request):
    return HttpResponse("Hello, Django!")

✅ Step 2: Configure URL Routing

Open myapp/urls.py and add:

from django.urls import path
from .views import home

urlpatterns = [
    path('', home),
]

✔ If urls.py doesn’t exist in myapp/, create it manually.

✅ Step 3: Link the App’s URL to the Project’s URL

Open myproject/urls.py and modify:

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', include('myapp.urls')),  # Include myapp URLs
]

✅ Step 4: Restart Server & Test

python manage.py runserver

✔ Open http://127.0.0.1:8000/ → You should see "Hello, Django!"

📌 6. Django Templates (HTML Frontend)

Django uses templates to separate logic from presentation.

✅ Step 1: Create a Templates Folder

Inside myapp/, create a folder:

myapp/
│── templates/
│   │── home.html  # HTML file

✅ Step 2: Create an HTML File (home.html)

<!DOCTYPE html>
<html>
<head>
    <title>My Django Page</title>
</head>
<body>
    <h1>Welcome to Django!</h1>
</body>
</html>

✅ Step 3: Modify views.py to Render the Template

from django.shortcuts import render

def home(request):
    return render(request, "home.html")

✔ Refresh http://127.0.0.1:8000/ → You should see the HTML page! 🎯

📌 7. Django Models (Database Handling)

Django models define database structure.

✅ Step 1: Create a Model in models.py

from django.db import models

class Product(models.Model):
    name = models.CharField(max_length=255)
    price = models.DecimalField(max_digits=10, decimal_places=2)

✅ Step 2: Apply Migrations

python manage.py makemigrations
python manage.py migrate

✔ This creates a database table for Product.

📌 8. Django Admin Panel

Django provides a built-in admin panel.

✅ Step 1: Create a Superuser

python manage.py createsuperuser

✔ Enter username, email, and password.

✅ Step 2: Register the Model in admin.py

from django.contrib import admin
from .models import Product

admin.site.register(Product)

✅ Step 3: Start the Server & Access Admin Panel

python manage.py runserver

✔ Go to http://127.0.0.1:8000/admin/
✔ Log in and manage database entries!

📌 9. Django Forms (Handling User Input)

Django has forms to handle user input.

✅ Step 1: Create a Form in forms.py

from django import forms
from .models import Product

class ProductForm(forms.ModelForm):
    class Meta:
        model = Product
        fields = ['name', 'price']

✅ Step 2: Use Form in views.py

from django.shortcuts import render
from .forms import ProductForm

def add_product(request):
    if request.method == "POST":
        form = ProductForm(request.POST)
        if form.is_valid():
            form.save()
    else:
        form = ProductForm()
    
    return render(request, "add_product.html", {"form": form})

✅ Step 3: Create add_product.html

<form method="POST">
    {% csrf_token %}
    {{ form.as_p }}
    <button type="submit">Add Product</button>
</form>

✔ Now, users can submit a product form!

📌 10. Django REST Framework (API Development)

To build REST APIs, install Django REST Framework:

pip install djangorestframework

✅ Step 1: Add to settings.py

INSTALLED_APPS = [
    'rest_framework',
    'myapp',
]

✅ Step 2: Create an API View in views.py

from rest_framework.response import Response
from rest_framework.decorators import api_view

@api_view(['GET'])
def api_home(request):
    return Response({"message": "Hello, API!"})

✅ Step 3: Define API URL

from django.urls import path
from .views import api_home

urlpatterns = [
    path('api/', api_home),
]

✔ Visit http://127.0.0.1:8000/api/ → You’ll see {"message": "Hello, API!"}

Tip: to enlarge your pyCharm editor

In the Settings/Preferences dialog ( Ctrl+Alt+S ), 
go to Editor | General (Mouse Control section). 
Select the Change font size with Ctrl+Mouse Wheel in option. 
Return to the editor, press and hold Ctrl , 
and using the mouse wheel, adjust the font size.

home

https://www.codingforentrepreneurs.com/guides/install-python-on-windows/
■ Installing django pip install django==2.1.5
■ Create Virtual environment python -m venv myenvname
■ Create django project django-admin startproject yourProjectName . where the period tell that your project was in current folder
■ Run project python manage.py runserver where manage.py is the module to manage django project
■ Create app in your project use multiple apps to control your project
■ Create your View
■ URL Mapping
■ Model
■ Migrations you can reset the database by deleting all the files in the migration and the
■ Admin register your app model in the admin.py
■ Python Shell Use python shell to register product
■ Templates {% block content%}{% endblock %} https://docs.djangoproject.com/en/4.0/ref/templates/builtins/
■ Form Create Product.objects.get(id=1) Create DB data
■ Raw HTML Form create your own input field without {{ form.as_p }}
■ Better way to insert data create a better insert data form
■ Form Widgets
■ Form Validation
■ Class Based Views ListView
■ Connect with PostgreSQL pip install psycopg2

home

Installing

  • open your project terminal in the pyCharm and type pip install django==2.1.5 where 2.1 is the version number
  • If you are in Windows and the error mentions something like: ... Connection aborted.', PermissionError ... Make sure you open the CMD with "Run as Administrator"

home

Create-Virtual-Environment

  • type pwd to see your location\
  • to create virtual env type python -m venv potatoscript - potatoscript is your env name
  • to activate the virtual env type .\potatoscript\Scripts\activate
  • Deactivate and reactivate To deactivate, just type: (potatoscript) deactivate To reactivate type: .\potatoscript\Scripts\activate

home

Create-App

  • each app is actually the python's package
  • type python manage.py startapp appname
  • python will create a package folder called appname for you and you can reuse it in your project or you can public it in the pip api for other people to use it
  • your will have a file called admin.py it is your login logout panel administrator CRUD
  • apps.py is your project configuration file

home

Create-View

  • open our views.py module
  • create a function with the http request parameter as below 
      from django.http import HttpResponse
  from django.shortcuts import render

  def index(request):
  return HttpResponse('Hello World')

home

URL-Mapping

  • to tell dJango that when user call /products -> index we need to Map the URL(Uniform Resource Locator -> Address)
  • go to our project app and create a python file called urls you must name it urls as requested by django 
    from django.urls import path
from . import views
# '' mean the root path
urlpatterns = [
   path('', views.index)
]
- Next we need to tell django where is our app
  - go to our project folder and select `urls.py` and type the following
  - we need to add `include` in the `from django.urls import path`

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path('admin/', admin.site.urls),
    path('products/', include('products.urls'))
]
  • to navigate to new path products\new create a new function in the views and add its path in the app's urls 
def new(request):
    return HttpResponse('New Page')
urlpatterns = [
    path('', views.index),
    path('new', views.new)
]
  • another way of mapping the url is just using one urls.py file as below
from django.contrib import admin
from django.urls import path
from products.views import index, new, about

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', index, name = 'index'),
    path('new/', new),
    path('about/', about),
]
  • the following is not a good practice
from django.contrib import admin
from django.urls import path

from pages import views

urlpatterns = [
    path('', views.home_view, name='home'),
    path('admin/', admin.site.urls),
]
  • you should change the above to the following
from django.contrib import admin
from django.urls import path

from pages.views import home_views, contact_view

urlpatterns = [
    path('', home_view, name='home'),
    path('contact/', contact_view, name='contact'),
    path('admin/', admin.site.urls),
]

home

Model

  • in the app models.py create a new class called Product
  • we need to inherit all the models module into the class
  • this models.Model contain all the behavior we want to CRUD it to database
from django.db import models

class Product(models.Model):
    name = models.CharField(max_length=255) #to prevent hacker to input something strange
    price = models.FloatField()
    stock = models.IntegerField()
    image = models.CharField(max_length=2083) #2083 is the max standard length in the input field

class Product2(models.Model):
    title       = models.CharField(max_length=120)
    description = models.TextField(blank=True, null=True)
    price       = models.DecimalField(decimal_places=2, max_degits=10000)
    summary     = models.TextField(default='this is cool') #summary     = models.TextField(blank=True, null=False)
    featured    = models.BooleanField() # null=True, default= True
  • after you add some data into the database without the featured field and you try to run the makemigrations it will give you error

image select 1 and then type True

home

Migrations

  • Use the models to create database table to storing product
  • go to browser and search for db browser for sqlite https://sqlitebrowser.org/ install the sqlite into our machine
  • and drag and drop our database file db.sqlite3 from our pyCharm
  • next go to our project folder and open setting.py and look for INSTALLED_APPS and include our ProductsCongfig path into it. To let django know where is our app
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'products.apps.ProductsConfig'
]
  • to auto create the table with the column fields as in our model type the following in the terminal python manage.py makemigrations
  • to generate our db table run the following in the terminal django will look for the pending migration python manage.py migrate

home

Admin

  • django by default come with the administration panel
  • let create a super user -> in the terminal python manage.py createsuperuser
  • it can let you manage your user just one line code as above and it also can let you manage your products
    • open the admin.py and type the following -> it tell django to register our Product into the admin
from django.contrib import admin
from .models import Product

admin.site.register(Product)

image

home

Python-Shell

  • at the root of your project type python manage.py shell
  • at the shell type >>>from products.models import Product
  • >>>Product.objects.all() to list out the queryset which is default in the django command
  • to create new item in the products type >>>Product.objects.create(title='New product 2', description='anotther one', price='200', summary='anything you like ')

home

Templates

  • Create a folder called Templates and register it in the Settings.py 
TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, "templates")],
        ...
    },
]
  • Create a base.html as Templates inheritance
...
    <body>
        {% block content %}
        share content
        {% endblock%}
        <p style="color:blue;font-size:12px">copyright by LIM 2022</p>
    </body>
...
  • Create the views page like home.html, contact.html, about.html and extend them to base.html 
{% extends 'base.html' %}
{% block content %}
<h1>This is homepage</h1>
{% endblock %}
  • setting in the urls.py 
from django.contrib import admin
from django.urls import path

from pages.views import home_view, contact_view, about_view

urlpatterns = [
    path('', home_view, name='home_view'),
    path('contact/', contact_view),
    path('about/', about_view),
    path('admin/', admin.site.urls),
]
  • Next we can include other template into our current template by using {% include 'navbar.html' %} 
    <body>
        {% include 'navbar.html' %}
        {% block content %}
        share content
        {% endblock%}
        <p style="color:blue;font-size:12px">copyright by LIM 2022</p>
    </body>
  • for loop in the template tag
{% extends 'base.html' %}

{% block content %}
<h1>This is Contact</h1>
<p>
    {{ my_text }}, my number is {{ my_number }}
</p>
<ul>
    {% for item in my_list %}
      {% if item == 321 %}
        <li>{{ forloop.counter }} - {{ item|add:1000 }}</li>
      {% elif item == "abc" %}
        <li>This is not a network</li>
      {% else %}
        <li>{{ forloop.counter }} - {{ item }}</li>
      {% endif %}
    {% endfor %}
</ul>
{% endblock %}

Form-Create

home

  • views.py in products
from django.shortcuts import render
from .models import Product

def product_detail_view(request):
    obj = Product.objects.get(id=1)
    #context = {
    #    "title": obj.title,
    #    "description": obj.description
    #}
    context = {
        'obj': obj
    }
    return render(request, "product/detail.html", context)
  • Form Create DB Step 1: create form.py 
from django import forms

from .models import Product

class ProductForm(forms.ModelForm):
    class Meta:
        model = Product
        fields = [
            'title',
            'description',
            'price'
        ]
  • Form Create DB Step 2: create view by adding the following in the views.py
from django.shortcuts import render

from .forms import ProductForm

from .models import Product


def product_create_view(request):
    form = ProductForm(request.POST or None)
    if form.is_valid():
        form.save()
        form = ProductForm() # this is to clear the input fields value after save
    context = {
        'form': form
    }
    return render(request, "products/product_create.html", context)
  • Form Create DB Step 3: create product_create.html inside the in app templates
{% extends "base.html" %}

{% block content %}
<form method="POST"> {% csrf_token %} # the csrf_token was for security of POST
    {{ form.as_p }} # this will generate the input fields base on the model for you automatically
    <input type='submit' value="Save" />
</form>
{% endblock %}
  • Form Create DB Step 4: add to urls.py 
from products.views import product_detail_view, product_create_view

urlpatterns = [
    path('', home_view, name='home_view'),
    path('contact/', contact_view),
    path('about/', about_view),
    path('create/', product_create_view),
    path('product/', product_detail_view),
    path('admin/', admin.site.urls),
]

Raw-HTML-Form

home

  • product_create.html
{% extends "base.html" %}

{% block content %}
<form action='.' method="POST"> {% csrf_token %}
    <!--{{ form.as_p }}-->
    <input type="text" name="title" placeholder="your title" />
    <input type='submit' value="Save" />
</form>
{% endblock %}
  • views.py
def product_create_view(request):
    #print(request.GET)
    #print(request.POST)
    if request.method == "POST":
        my_new_title = request.POST.get('title')
        print(my_new_title)
        # Product.objects.create(title=my_new_title)
    context = {}
    return render(request, "products/product_create.html", context)

Better-Create

home

  • views.py
def product_create_view(request):
    form = RawProductForm() # to initial the form look like 
    if request.method == "POST":
        form = RawProductForm(request.POST) # use request.POST to do some action
        if form.is_valid():
            #now the data is good
            #print(form.cleaned_data) #cleaned_data is the data come from the form after you submit it
            Product.objects.create(**form.cleaned_data) #we need to use ** to pass the data as argument
            form = RawProductForm()
        else:
            print(form.errors)
    context = {
        "form" : form
    }
    return render(request, "products/product_create.html", context)
  • product_create.html
{% extends "base.html" %}

{% block content %}
<form action='.' method="POST"> {% csrf_token %}
    <!--{{ form.as_p }}-->
    <!--<input type="text" name="title" placeholder="your title" />-->
    {{ form.as_p }} <!--you can change the display style to as_ul or as_p or ...-->
    <input type='submit' value="Save" />
</form>
{% endblock %}

Form-Widgets

home

  • use the form widget you can overwrite the thing in the form
class RawProductForm(forms.Form):
    title       = forms.CharField(label='', widget=forms.TextInput(attrs={"placeholder":"my title"}))
    description = forms.CharField(
                        required=False, 
                        widget=forms.Textarea(
                            attrs={
                                "class": "new-class-name two",
                                "rows": 20,
                                "cols": 90,
                                "id": "my_textarea_id"
                            }
                        ))
    price       = forms.DecimalField(initial=200)

Form-Validation

home

class ProductForm(forms.ModelForm):
    title       = forms.CharField(label='', widget=forms.TextInput(attrs={"placeholder":"my title"}))
    email       = forms.EmailField()
    description = forms.CharField(
                        required=False, 
                        widget=forms.Textarea(
                            attrs={
                                "placeholder": "Your description",
                                "class": "new-class-name two",
                                "rows": 20,
                                "cols": 90,
                                "id": "my_textarea_id"
                            }
                        ))
    price       = forms.DecimalField(initial=200)

    class Meta:
        model = Product
        fields = [
            'title',
            'description',
            'price'
        ]
    
    def clean_title(self, *args, **kwargs):
        title = self.cleaned_data.get("title")
        if not "CFE" in title:
            raise forms.ValidationError("This is not a valid title")
        if not "news" in title:
            raise forms.ValidationError("This is not a valid title")    
        else:
            return title

    def clean_email(self, *args, **kwargs):
        email = self.cleaned_data.get("email")
        if not email.endswith("edu"):
            raise forms.ValidationError("This is not a valid email")  
        else:
            return email

Class-Based-Views

home

  • views.py
from django.shortcuts import render

from django.views.generic import(
    CreateView,
    DetailView,
    ListView,
    UpdateView,
    DeleteView
)

from .models import Article

class ArticleListView(ListView):
    template_name = 'articles/article_list.html'
    queryset = Article.objects.all() # <blog>/<modelname>_list.html
  • in app url.py
from django.urls import path
from .views import(
    ArticleListView
)

app_name = 'articles'
urlpatterns = [
    path('', ArticleListView.as_view(), name='article-list')
]

Connect-PostgreSQL

home

  1. install djangorestframework pip install djangorestframework
  2. install psycopg2 pip install psycopg2 


              


          



  
          

            


            
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