GitLocker: The Coding Marketplace

Description:

djangorestframeworktricks 0.2.14

Collection of various tricks for
Django REST framework.

Prerequisites

Django 2.2, 3.0, 3.1, 3.2, 4.0 and 4.1.
Python 3.7, 3.8, 3.9, 3.10 and 3.11.

Dependencies

djangorestframework: Initially written with 3.6.3, but nowadays tested
with >=3.10,<3.14. May (still) work on earlier- or (even) support
later- versions, although not guaranteed.

Installation

Install latest stable version from PyPI:
pip install django-rest-framework-tricks
or latest development version from GitHub:
pip install https://github.com/barseghyanartur/django-rest-framework-tricks/archive/master.tar.gz

Add rest_framework and rest_framework_tricks to INSTALLED_APPS:
INSTALLED_APPS = (
# ...
# REST framework
'rest_framework',

# REST framework tricks (this package)
'rest_framework_tricks',

# ...
)

Documentation
Documentation is available on Read the Docs.

Main features and highlights

Nested serializers: Nested (writable) serializers for non-relational fields.
Ordering filter: Developer friendly names for ordering options (for
instance, for related field names).
File field with restrictions: Restrict the file field (in size).

Usage examples

Nested serializers
Nested serializers for non-relational fields.
Our imaginary Book model consists of the following (non-relational) Django
model fields:

title: CharField
description: TextField
summary: TextField
publication_date: DateTimeField
state: CharField (with choices)
isbn: CharField
price: DecimalField
pages: IntegerField
stock_count: IntegerField

In our REST API, we want to split the Book serializer into parts using nested
serializers to have the following structure:
{
"id": "",
"title": "",
"description": "",
"summary": "",
"publishing_information": {
"publication_date": "",
"isbn": "",
"pages": ""
},
"stock_information": {
"stock_count": "",
"price": "",
"state": ""
}
}

Sample model
The only variation from standard implementation here is that we declare two
NestedProxyField fields on the Book model level for to be used in
BookSerializer serializer.
Note, that the change does not cause model change (no migrations or
whatsoever).

Required imports
from django.db import models

from rest_framework_tricks.models.fields import NestedProxyField

Model definition
BOOK_PUBLISHING_STATUS_PUBLISHED = 'published'
BOOK_PUBLISHING_STATUS_NOT_PUBLISHED = 'not_published'
BOOK_PUBLISHING_STATUS_IN_PROGRESS = 'in_progress'
BOOK_PUBLISHING_STATUS_CHOICES = (
(BOOK_PUBLISHING_STATUS_PUBLISHED, "Published"),
(BOOK_PUBLISHING_STATUS_NOT_PUBLISHED, "Not published"),
(BOOK_PUBLISHING_STATUS_IN_PROGRESS, "In progress"),
)
BOOK_PUBLISHING_STATUS_DEFAULT = BOOK_PUBLISHING_STATUS_PUBLISHED

class Book(models.Model):
"""Book."""

title = models.CharField(max_length=100)
description = models.TextField(null=True, blank=True)
summary = models.TextField(null=True, blank=True)
publication_date = models.DateField()
state = models.CharField(max_length=100,
choices=BOOK_PUBLISHING_STATUS_CHOICES,
default=BOOK_PUBLISHING_STATUS_DEFAULT)
isbn = models.CharField(max_length=100, unique=True)
price = models.DecimalField(max_digits=10, decimal_places=2)
pages = models.PositiveIntegerField(default=200)
stock_count = models.PositiveIntegerField(default=30)

# List the fields for `PublishingInformationSerializer` nested
# serializer. This does not cause a model change.
publishing_information = NestedProxyField(
'publication_date',
'isbn',
'pages',
)

# List the fields for `StockInformationSerializer` nested serializer.
# This does not cause a model change.
stock_information = NestedProxyField(
'stock_count',
'price',
'state',
)

class Meta:
"""Meta options."""

ordering = ["isbn"]

def __str__(self):
return self.title

Sample serializers
At first, we add nested_proxy_field property to the Meta class
definitions of PublishingInformationSerializer and
StockInformationSerializer nested serializers.
Then we define our (main) BookSerializer class, which is going to be
used as a serializer_class of the BookViewSet. We inherit the
BookSerializer from
rest_framework_tricks.serializers.HyperlinkedModelSerializer
instead of the one of the Django REST framework. There’s also a
rest_framework_tricks.serializers.ModelSerializer available.

Required imports
from rest_framework import serializers
from rest_framework_tricks.serializers import (
HyperlinkedModelSerializer,
)

from .models import Book

Defining the serializers

Note
If you get validation errors about null-values, add allow_null=True
next to the required=False for serializer field definitions.

Nested serializer
class PublishingInformationSerializer(serializers.ModelSerializer):
"""Publishing information serializer."""

publication_date = serializers.DateField(required=False)
isbn = serializers.CharField(required=False)
pages = serializers.IntegerField(required=False)

class Meta:
"""Meta options."""

model = Book
fields = (
'publication_date',
'isbn',
'pages',
)
# Note, that this should be set to True to identify that
# this serializer is going to be used as `NestedProxyField`.
nested_proxy_field = True
Nested serializer
class StockInformationSerializer(serializers.ModelSerializer):
"""Stock information serializer."""

class Meta:
"""Meta options."""

model = Book
fields = (
'stock_count',
'price',
'state',
)
# Note, that this should be set to True to identify that
# this serializer is going to be used as `NestedProxyField`.
nested_proxy_field = True
Main serializer to be used in the ViewSet
# Note, that we are importing the ``HyperlinkedModelSerializer`` from
# the `rest_framework_tricks.serializers`. Names of the serializers
# should match the names of model properties set with ``NestedProxyField``
# fields.
class BookSerializer(HyperlinkedModelSerializer):
"""Book serializer."""

publishing_information = PublishingInformationSerializer(required=False)
stock_information = StockInformationSerializer(required=False)

class Meta:
"""Meta options."""

model = Book
fields = (
'url',
'id',
'title',
'description',
'summary',
'publishing_information',
'stock_information',
)

Sample ViewSet
Absolutely no variations from standard implementation here.

Required imports
from rest_framework.viewsets import ModelViewSet
from rest_framework.permissions import AllowAny

from .models import Book
from .serializers import BookSerializer

ViewSet definition
class BookViewSet(ModelViewSet):
"""Book ViewSet."""

queryset = Book.objects.all()
serializer_class = BookSerializer
permission_classes = [AllowAny]

Sample OPTIONS call
OPTIONS /books/api/books/
HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept
{
"name": "Book List",
"description": "Book ViewSet.",
"renders": [
"application/json",
"text/html"
],
"parses": [
"application/json",
"application/x-www-form-urlencoded",
"multipart/form-data"
],
"actions": {
"POST": {
"id": {
"type": "integer",
"required": false,
"read_only": true,
"label": "ID"
},
"title": {
"type": "string",
"required": true,
"read_only": false,
"label": "Title",
"max_length": 100
},
"description": {
"type": "string",
"required": false,
"read_only": false,
"label": "Description"
},
"summary": {
"type": "string",
"required": false,
"read_only": false,
"label": "Summary"
},
"publishing_information": {
"type": "nested object",
"required": false,
"read_only": false,
"label": "Publishing information",
"children": {
"publication_date": {
"type": "date",
"required": false,
"read_only": false,
"label": "Publication date"
},
"isbn": {
"type": "string",
"required": false,
"read_only": false,
"label": "Isbn"
},
"pages": {
"type": "integer",
"required": false,
"read_only": false,
"label": "Pages"
}
}
},
"stock_information": {
"type": "nested object",
"required": false,
"read_only": false,
"label": "Stock information",
"children": {
"stock_count": {
"type": "integer",
"required": false,
"read_only": false,
"label": "Stock count"
},
"price": {
"type": "decimal",
"required": true,
"read_only": false,
"label": "Price"
},
"state": {
"type": "choice",
"required": false,
"read_only": false,
"label": "State",
"choices": [
{
"value": "published",
"display_name": "Published"
},
{
"value": "not_published",
"display_name": "Not published"
},
{
"value": "in_progress",
"display_name": "In progress"
}
]
}
}
}
}
}
}

Unlimited nesting depth
Unlimited nesting depth is supported.
Our imaginary Author model could consist of the following (non-relational)
Django model fields:

salutation: CharField
name: CharField
email: EmailField
birth_date: DateField
biography: TextField
phone_number: CharField
website: URLField
company: CharField
company_phone_number: CharField
company_email: EmailField
company_website: URLField

In our REST API, we could split the Author serializer into parts using
nested serializers to have the following structure:
{
"id": "",
"salutation": "",
"name": "",
"birth_date": "",
"biography": "",
"contact_information": {
"personal_contact_information": {
"email": "",
"phone_number": "",
"website": ""
},
"business_contact_information": {
"company": "",
"company_email": "",
"company_phone_number": "",
"company_website": ""
}
}
}
Our model would have to be defined as follows (see Advanced usage examples
for complete model definition):
class Author(models.Model):
"""Author."""

# ...

# List the fields for `PersonalContactInformationSerializer` nested
# serializer. This does not cause a model change.
personal_contact_information = NestedProxyField(
'email',
'phone_number',
'website',
)

# List the fields for `BusinessContactInformationSerializer` nested
# serializer. This does not cause a model change.
business_contact_information = NestedProxyField(
'company',
'company_email',
'company_phone_number',
'company_website',
)

# List the fields for `ContactInformationSerializer` nested
# serializer. This does not cause a model change.
contact_information = NestedProxyField(
'personal_contact_information',
'business_contact_information',
)

# ...
See the Advanced usage examples
for complete example.

Ordering filter
Developer friendly names for ordering options (for instance, for related field
names) for making better APIs.

Sample model
Absolutely no variations from standard implementation here.

Required imports
from django.db import models

Model definition
class Profile(models.Model):
"""Profile."""

user = models.ForeignKey('auth.User')
biography = models.TextField()
hobbies = models.TextField()

Sample serializer
Absolutely no variations from standard implementation here.

Required imports
from rest_framework import serializers

from .models import Profile

Defining the serializers
class ProfileSerializer(serializers.ModelSerializer):
"""Profile serializer."""

username = serializers.CharField(source='user.username', read_only=True)
full_name = serializers.SerializerMethodField()
email = serializers.CharField(source='user.email', read_only=True)

class Meta(object):

model = Profile
fields = (
'id',
'username',
'full_name',
'email',
'biography',
'hobbies',
)

def get_full_name(self, obj):
return obj.user.get_full_name()

Sample ViewSet
The only variation from standard implementation here is that we
use rest_frameworks_tricks.filters.OrderingFilter instead
of rest_framework.filters.OrderingFilter.

Required imports
from rest_framework.viewsets import ModelViewSet
from rest_framework.permissions import AllowAny
from rest_framework_tricks.filters import OrderingFilter

from .models import Profile
from .serializers import ProfileSerializer

ViewSet definition
class ProfileViewSet(ModelViewSet):
"""Profile ViewSet."""

queryset = Profile.objects.all()
serializer_class = ProfileSerializer
permission_classes = [AllowAny]
filter_backends = (OrderingFilter,)
ordering_fields = {
'id': 'id',
'username': 'user__username',
'email': 'user__email',
'full_name': ['user__first_name', 'user__last_name']
}
ordering = ('id',)

Sample GET calls
Note, that our ordering options are now equal to the field names in the
serializer (JSON response). API becomes easier to use/understand that way.
GET /api/profile/?ordering=email
GET /api/profile/?ordering=-username
GET /api/profile/?ordering=full_name
GET /api/profile/?ordering=-full_name

File field with restrictions

Sample model
Absolutely no variations from standard implementation here.

Required imports
from django.db import models

Model definition
class Profile(models.Model):
"""Upload."""

username = models.CharField(max_length=255)
resume = models.FileField()

Sample serializer

Required imports
from rest_framework import serializers
from rest_framework_tricks.fields import ConstrainedFileField

from .models import Upload

Defining the serializers
class ProfileSerializer(serializers.ModelSerializer):
"""Profile serializer."""

username = serializers.CharField()
# Restrict resume to 5Mb
resume = ConstrainedFileField(max_upload_size=5_242_880)

class Meta(object):

model = Profile
fields = (
'id',
'username',
'resume',
)

Demo
Run demo locally
In order to be able to quickly evaluate the django-rest-framework-tricks,
a demo app (with a quick installer) has been created (works on Ubuntu/Debian,
may work on other Linux systems as well, although not guaranteed). Follow the
instructions below to have the demo running within a minute.
Grab and run the latest rest_framework_tricks_demo_installer.sh demo
installer:
wget -O - https://raw.github.com/barseghyanartur/django-rest-framework-tricks/master/examples/rest_framework_tricks_demo_installer.sh | bash
Open your browser and test the app.
http://127.0.0.1:8001/books/api/

Testing
Project is covered with tests.
To test with all supported Python/Django versions type:
tox
To test against specific environment, type:
tox -e py39-django32
To test just your working environment type:
pytest -vvv
To run a single test in your working environment type:
pytest -vvv src/rest_framework_tricks/tests/test_nested_proxy_field.py
pip install -r examples/requirements/test.txt

Writing documentation
Keep the following hierarchy.
=====
title
=====

header
======

sub-header
----------

sub-sub-header
~~~~~~~~~~~~~~

sub-sub-sub-header
^^^^^^^^^^^^^^^^^^

sub-sub-sub-sub-header
++++++++++++++++++++++

sub-sub-sub-sub-sub-header
**************************

License
GPL-2.0-only OR LGPL-2.1-or-later

Support
For any issues contact me at the e-mail given in the Author section.

Author
Artur Barseghyan <artur.barseghyan@gmail.com>