Skip to main content

Django REST Framework and SQLAlchemy integration

Project description

Django REST Witchcraft

Build Status Read The Docs PyPI version Coveralls Status

Django REST Framework integration with SQLAlchemy

django-rest-witchcraft is an extension for Django REST Framework that adds support for SQLAlchemy. It aims to provide a similar development experience to building REST api’s with Django REST Framework with Django ORM, except with SQLAlchemy.

Installation

pip install django-rest-witchcraft

Quick Start

First up, lets define some simple models:

import sqlalchemy as sa
import sqlalchemy.orm  # noqa
from sqlalchemy.ext.declarative import declarative_base

engine = sa.create_engine('sqlite:///:memory:', echo=True)
session = sa.orm.scoped_session(sa.orm.sessionmaker(bind=engine))

Base = declarative_base()
Base.query = session.query_property()


class Group(Base):
    __tablename__ = 'groups'

    id = sa.Column(sa.Integer(), primary_key=True, autoincrement=True)
    name = sa.Column(sa.String())


class User(Base):
    __tablename__ = 'users'

    id = sa.Column(sa.Integer(), primary_key=True, autoincrement=True)
    name = sa.Column(sa.String())
    fullname = sa.Column(sa.String())
    password = sa.Column(sa.String())

    _group_id = sa.Column('group_id', sa.Integer(), sa.ForeignKey('groups.id'))
    group = sa.orm.relationship(Group, backref='users')


class Address(Base):
    __tablename__ = 'addresses'

    id = sa.Column(sa.Integer(), primary_key=True, autoincrement=True)
    email_address = sa.Column(sa.String(), nullable=False)

    _user_id = sa.Column(sa.Integer(), sa.ForeignKey('users.id'))
    user = sa.orm.relationship(User, backref='addresses')

Base.metadata.create_all(engine)

Nothing fancy here, we have a User class that can belongs to a Group instance and has many Address instances

This serializer can handle nested create, update or partial update operations.

Lets define a serializer for User with all the fields:

class UserSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        session = session
        fields = '__all__'

This will create the following serializer for us:

>>> serializer = UserSerializer()

>>> serializer
UserSerializer():
    id = IntegerField(allow_null=False, help_text=None, label='Id', required=True)
    name = CharField(allow_null=True, help_text=None, label='Name', max_length=None, required=False)
    fullname = CharField(allow_null=True, help_text=None, label='Fullname', max_length=None, required=False)
    password = CharField(allow_null=True, help_text=None, label='Password', max_length=None, required=False)
    group = GroupSerializer(allow_null=True, is_nested=True, required=False):
        id = IntegerField(allow_null=False, help_text=None, label='Id', required=False)
        name = CharField(allow_null=True, help_text=None, label='Name', max_length=None, required=False)
    addresses = AddressSerializer(allow_null=True, many=True, required=False):
        id = IntegerField(allow_null=False, help_text=None, label='Id', required=False)
        email_address = CharField(allow_null=False, help_text=None, label='Email_address', max_length=None, required=True)
    url = UriField(read_only=True)

Lets try to create a User instance with our brand new serializer:

serializer = UserSerializer(data={
    'name': 'shosca',
    'password': 'swordfish',
})
serializer.is_valid()
serializer.save()

user = serializer.instance

This will create the following user for us:

>>> user
User(_group_id=None, id=1, name='shosca', fullname=None, password='swordfish')

Lets try to update our user User instance and change its password:

serializer = UserSerializer(user, data={
    'name': 'shosca',
    'password': 'password',
})
serializer.is_valid()
serializer.save()

user = serializer.instance

Our user now looks like:

>>> user
User(_group_id=None, id=1, name='shosca', fullname=None, password='password')

Lets try to update our User instance again, but this time lets change its password only:

serializer = UserSerializer(user, data={
    'password': 'swordfish',
}, partial=True)
serializer.is_valid()
serializer.save()

user = serializer.instance

This will update the following user for us:

>>> user
User(_group_id=None, id=1, name='shosca', fullname=None, password='swordfish')

Our user does not belong to a Group, lets fix that:

group = Group(name='Admin')
session.add(group)
session.flush()

serializer = UserSerializer(user, data={
    'group': {'id': group.id
})
serializer.is_valid()
serializer.save()

user = serializer.instance

Now, our user looks like:

>>> user
User(_group_id=1, id=1, name='shosca', fullname=None, password='swordfish')

>>> user.group
Group(id=1, name='Admin')

We can also change the name of our user’s group through the user using nested updates:

class UserSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        session = session
        fields = '__all__'
        extra_kwargs = {
            'group': {'allow_nested_updates': True}
        }

serializer = UserSerializer(user, data={
    'group': {'name': 'Super User'}
}, partial=True)
serializer.is_valid()

user = serializer.save()

Now, our user looks like:

>>> user
User(_group_id=1, id=1, name='shosca', fullname=None, password='swordfish')

>>> user.group
Group(id=1, name='Super User')

We can use this serializer in a viewset like:

from rest_witchcraft import viewsets

class UserViewSet(viewsets.ModelViewSet):
    queryset = User.query
    serializer_class = UserSerializer

And we can register this viewset in our urls.py like:

from rest_witchcraft import routers

router = routers.DefaultRouter()
router.register(r'users', UserViewSet)

urlpatterns = [
    ...
    url(r'^', include(router.urls)),
    ...
]

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

django-rest-witchcraft-0.5.5.tar.gz (41.7 kB view hashes)

Uploaded Source

Built Distribution

django_rest_witchcraft-0.5.5-py2.py3-none-any.whl (18.9 kB view hashes)

Uploaded Python 2 Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page