This document provides an overview of Django, a popular Python web framework. It discusses key features of Django including its MVT architecture, ORM, admin interface, and template system. It also covers common Django practices like project structure, apps, settings, models, views, URLs, forms, and using the Django REST framework to build APIs. Major sections include installation, configuration, building models, views, templates, and forms.

1. Python Web Framework

2. 2
Django?

3. 3
Django?

4. 4
Django
 A high-level Python web framework
 Created in 2003, open sourced in 2005
 Encourages rapid development and clean, pragmatic design
 Widely supported, many deployment options
 Focus on automation and DRY
 “For perfectionists with deadlines”
 MVC (MTV) Architecture

5. 5
Who uses Django?
 BitBucket
 DISQUS (serving 400 million people)
 Pinterest
 Instagram
 dPaste
 Mozilla (support.mozill, addons.mozilla)
 NASA
 PBS (Public Broadcasting Service)
 The Washington Post, NY Times, LA Times, The Guardian
 National Geographic, Discovery Channel

6. 6
Features
 Object Relational Mapper - ORM
 Template System
 customizable Admin Interface, makes CRUD easy
 Built-in light weight Web Server
 URL design
 Authentication / Authorization
 Internationalization support
 Cache framework, with multiple cache mechanisms
 Free, and Great Documentation

7. MVC vs. MTV
M
Model
V
View
C
Controller
M
Model
T
Template
V
View

8. 8
Installation
 Prerequisites
 Python
 PIP for installing Python packages
 pip install Django
 pip install mysql-python
 Testing installation
 import django
 Create a requirements.txt
 $ pip install -r requirements.txt

9. 9
Virtualenv
 pip “one project, one virtualenv”
 projects with different dependencies, package versions
 easier to deploy. Forget dependency hell!

10. 10
Django Architecture
Models Describes your data
Views Controls what users sees
Templates How user sees it
Controller URL dispatcher
DataBase
Model
View
Template URL dispatcher
Brower

11. 11
Project Creation
 Creating new Project
 django-admin.py startproject demoproject
A project is a collection of applications
 Creating new Application
 python manage.py startapp demosite
An application tries to provide a single, relatively self-contained set of related functions
 Using the built-in web server
 python manage.py runserver
Runs by default at port 8000

12. 12
Project Directory Structure
demosite/
manage.py.
demosite/
__init__.py
settings.py
urls.py
wsgi.py
templates/
static/
demoapp/
__init__.py
urls.py
views.py
models.py
admin.py
forms.py

13. 13
Apps
 use short, obvious, single-word names for your apps
 many small apps is better than a few giant apps:
 explain an app in a sentence. If you can't, split the app
 rather than expand an app, write a new app
 don't reinvent the wheel!
 django.contrib
 3rd-party apps

14. 14
Settings
 use - multiple settings files: - per environment:
 dev, testing, staging, production - per developer (local settings)
 all settings files must inherit from base, so you can do:
 INSTALLED_APPS += ('debug_toolbar', ) - version control all the settings!

15. 15
Models
you can use Django without a database
Or
describe your database layout in Python code with django ORM

16. 16
Models
from django.db import models
class Reporter(models.Model):
full_name = models.CharField(max_length=70)
def __str__(self): # __unicode__ on Python 2
return self.full_name
class Article(models.Model):
pub_date = models.DateField()
headline = models.CharField(max_length=200)
content = models.TextField() reporter = models.ForeignKey(Reporter)
def __str__(self): # __unicode__ on Python 2
return self.headline

17. 17
admin
from django.contrib import admin
from . import models
admin.site.register(models.Article)

18. 18
URLs
 Map URLs in requests to code that can be executed
 Regular expressions!
 Subsections of your site can have their own urls.py modules

19. 19
URLs
 Root URL should be configured in settings.py
o ROOT_URLCONF = 'app.urls'
 Example
urlpatterns = patterns(' ',
(r'^articles-year/$', 'mysite.news.views.articles_year'),
)

20. 20
Views
 Map Code that handles requests
 Other frameworks often call these “controllers”
 Basically a function that:
 gets a request
 returns text or a response

21. 21
Views
from django.shortcuts import render
from .models import Article
def year_archive(request, year):
a_list = Article.objects.filter(pub_date__year=year)
context = {'year': year, 'article_list': a_list}
return render(request, 'news/year_archive.html', context)

22. 22
Django Template Language
 Call a function or do logic:
{% ... %}
 Variable substitution:
{{ bar }}
 Filters:
{{ foo|bar }}

23. 23
Django Template Language
{% extends "base.html" %}
{% block title %}Articles for {{ year }}{% endblock %}
{% block content %}
<h1>Articles for {{ year }}</h1>
{% for article in article_list %}
<p>{{ article.headline }}</p>
<p>By {{ article.reporter.full_name }}</p>
<p>Published {{ article.pub_date|date:"F j, Y" }}</p>
{% endfor %}
{% endblock %}

24. 24
Django Template Language (base)
{% load staticfiles %}
<html>
<head>
<title>{% block title %}{% endblock %}</title>
</head>
<body>
<img src="{% static "images/sitelogo.png" %}" alt="Logo" />
{% block content %}{% endblock %}
</body>
</html>

25. 25
Form
from django import forms
class MyForm(forms.Form):
name = forms.CharField(max_length=30)
email = forms.EmailField()

26. 26
Using a Form in a View
from myapp.forms import MyForm
def my_view(request):
form = MyForm(request.POST or None)
if request.method == "POST" and form.is_valid():
name = form.cleaned_data['name']
email = form.cleaned_data['email']
# do something great with that data
return render(request, 'myapp/myform.html', { 'form': form })

27. 27
Forms in Templates
<html>
...
<body>
<form action="{% url 'myapp:my_form' %}" method="post">
{% csrf_token %}
{{ form.as_p }}
<button type="submit">Go!</button>
</form>
</body>
</html>

28. 28
Django-rest-framework
Django REST framework is a powerful and flexible toolkit for building Web APIs.

29. 29
Django-rest-framework (installation)
 pip install djangorestframework
 pip install django-rest-swagger
 Pip install django-filter

30. 30
Django-rest-framework (installation)
# settings.py
INSTALLED_APPS = (
...
‘rest_framework’,
)