Django & Django REST Framework Notes

Setup Project

Virtual Environment

python -m venv .venv
. .venv/bin/activate
pip install django
pip install djangorestframework

pip install markdown			
# Markdown support for the browsable API

pip install django-filter		
# Filtering support

pip install djangorestframework-simplejwt	
# JWT auth

pip install coreapi
# Depricated, use OpenAI instaed

Start Project and App

django-admin startproject DRF_API_Base .
django-admin startapp base_app

python manage.py makemigrations
python manage.py migrate

python manage.py migrate createsuperuser

Update database

python manage.py makemigrations
python manage.py migrate

Use MySQL(skipped)

Configure Project Level Settings

DRF_API_Base/settings.py

LANGUAGE_CODE = 'zh-hans'
TIME_ZONE = 'Asia/Shanghai'

# Media folder
STATIC_URL = 'static/'
MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
MEDIA_URL = '/media/'

# Add custom apps
INSTALLED_APPS = [
] + [
    'base_app'
]

Define Relationships in Django

Many-to-Many

Should be defined on either side of the relationship using ManyToManyField(). (Notice that Category was passed as a string, because the class Category was not defined yet. Django uses a string representation and it’s considered the best practice.)

# One product can belongs to many categories, such as bread -> food & on_sale_product
# One category can also has many products, such as food -> bread & chicken
class Product(models.Model):
    name = models.CharField(max_length=50)
    categories = models.ManyToManyField('Category')

    
class Category(models.Model):
    name = models.CharField(max_length=50)

Many-to-One

Should be defined on the “many” side of the relationship using ForeignKey()

class Order(models.Model):
    order_number = models.CharField(max_length=50)
    customer = models.ForeignKey('Customer', on_delete=models.CASCADE)

    
class Customer(models.Model):
    name = models.CharField(max_length=50)

The kwarg: related_name

class Author(models.Model):
    name = models.CharField(max_length=50)
    
 
# Case 1
class Book(models.Model):
    title = models.CharField(max_length=200)
    author = models.ForeignKey('Author', on_delete=models.CASCADE)

author = Author.objects.all(name='Zheng Yuan')
books = author.book_set.all()  
# Default method <class_lowercase>_set

# Case 2
class Book(models.Model):
    title = models.CharField(max_length=200)
    author = models.ForeignKey('Author', 
                               related_name='books',
                               on_delete=models.CASCADE)

books = author.books.all()
# Now, the method now becomes the value of related_name

One-to-One

Should be defined on either side of the relationship using OneToOneField()

DRF Views

DRF provides APIView, a subclass of Django’s View, with the following differences:

• Input: Requests became DRF’s Request instead of Django’s HttpRequest instances.
• Output: returns DRF’s Response instead of Django’s HttpResponse instances.
• APIException will be caught and mediated into appropriate responses.
• Incoming requests will be authenticated and appropriate permission and/or throttle checks will be run before dispatching the request to the handler method.

Class-based Views

Function-Based Views

API Policy Decorators

View Schema Decorator

Generic Views

Doc Reference

Minxins

ViewSets

Doc Reference