Django Channels Rest Framework

Django Channels Rest Framework provides a DRF like interface for building channels-v2 websocket consumers.

This project can be used alongside HyperMediaChannels and ChannelsMultiplexer to create a Hyper Media Style api over websockets. However Django Channels Rest Framework is also a free standing framwork with the goal of providing an api that is familiar to DRF users.

Thanks to

DCRF is based of a fork of Channels Api and of course inspired by Django Rest Framework.

Install

pip install djangochannelsrestframework

How to Use

Observing a Model instance

Consumer that accepts subscribtions to an instance.

class TestConsumer(ObserverModelInstanceMixin, GenericAsyncAPIConsumer):
    queryset = get_user_model().objects.all()
    serializer_class = UserSerializer

this exposes the retrieve and subscribe_instance actions to that instance.

to subscribe send:

{
    "action": "subscribe_instance",
    "pk": 42,  # the id of the instance you are subscribing to
    "request_id": 4  # this id will be used for all resultent updates.
}

Actions will be sent down out from the server:

{
    "action": "update",
    "errors": [],
    "response_status": 200,
    "request_id": 4,
    "data": {'email': '42@example.com', 'id': 42, 'username': 'thenewname'},
}

Adding Custom actions

class UserConsumer(GenericAsyncAPIConsumer):
    queryset = get_user_model().objects.all()
    serializer_class = UserSerializer

    @action()
    async def send_email(self, pk=None, to=None, **kwargs):
        user = await database_sync_to_async(self.get_object)(pk=pk)
        # ... do some stuff
        # remember to wrap all db actions in `database_sync_to_async`
        return {}, 200  # return the contenct and the response code.

    @action()  # if the method is not async it is already wrapped in `database_sync_to_async`
    def publish(self, pk=None, **kwargs):
        user = self.get_object(pk=pk)
    # ...
    return {'pk': pk}, 200

You can also use any of:

CreateModelMixin
ListModelMixin
RetrieveModelMixin
UpdateModelMixin
PatchModelMixin
DeleteModelMixin

just as you would in DRF.

from djangochannelsrestframework.generics import GenericAsyncAPIConsumer
from djangochannelsrestframework.mixins import (
    RetrieveModelMixin,
    UpdateModelMixin
)

class UserConsumer(RetrieveModelMixin, UpdateModelMixin, GenericAsyncAPIConsumer):
    queryset = get_user_model().objects.all()
    serializer_class = UserSerializer

Consumers that are not bound to Models

You can also create consumers that are not at all related to any models.

from djangochannelsrestframework.decorators import action
from djangochannelsrestframework.consumers import AsyncAPIConsumer

class MyConsumer(AsyncAPIConsumer):

    @action()
    async def an_async_action(self, some=None, **kwargs):
        # do something async
    return {'response with': 'some message'}, 200

    @action()
    def a_sync_action(self, pk=None, **kwargs):
        # do something sync
    return {'response with': 'some message'}, 200

Using your normal views over a websocket connection

from djangochannelsrestframework.consumers import view_as_consumer

application = ProtocolTypeRouter({
    "websocket": AuthMiddlewareStack(
        URLRouter([
        url(r"^front(end)/$", view_as_consumer(YourDjangoView)),
    ])
    ),
 })

onekiloparsec / djangochannelsrestframework