DRF channels one-way WS

Simple one-way bindings for django-channels with some specific support for django-rest-framework serializers and websockets. I.e. enrich your existing API with push notifications.

Installation

• pipenv install drf-channels-oneway-ws or pip install drf-channels-oneway-ws

Usage

Bindings

from django.db import models
from rest_framework import serializers
from channels_oneway.bindings import Binding

class Family(models.Model):
    name = models.CharField(max_length=255)

class Bird(models.Model):
    name = models.CharField(max_length=255)
    family = models.ForeignKey('Family', models.CASCADE)


class BirdSerializer(serializers.ModelSerializer):
    class Meta:
        model = Customer
        fields = ('__all__')


class BirdBinding(Binding):
    model = Bird
    stream = 'birds'
    serializer = BirdSerializer

    @classmethod
    def group_names(cls, instance):
        return [instance.family.name]

class FamilyBinding(Binding):
    """
    example of a binding not using a drf serializer
    """
    model = Family
    stream = 'bird-families'

    @classmethod
    def group_names(cls, instance):
        return [instance.name]

    def serialize_data(self, instance):
        return {'id': instance.id, 'name': instance.name}

Now you make sure you have a WebsocketConsumer, which does something like self.channel_layer.group_add('thrushes', self.channel_name) in its connect coroutine. Family.objects.create(name='thrushes') will then cause the following to be sent over the associated websocket:

{
    "stream": "bird-families",
    "payload": {
        "action": "create",
        "data": {"id": 1, "name": "thrushes"},
        "model": "your_app.family",
        "pk": 1
    }
}

Upon modification ("action": "update") or deletion ("action": "delete") you will receive messages with an equal structure.

Registration

In order to let the bindings register their signals make sure they are imported at some point. In case you use a dedicated file, import it from AppConfig.ready just like your signals.

Helpers

In order to send a ws message from outside a binding, but using the same format (stream + payload) (and also the drf json encoder) use the async channels_oneway.utils.groupSend(group, stream, payload) or its sync equivalent groupSendSync.

Contributing

Installation

• git clone git@github.com:evocount/drf-channels-oneway-ws.git
• cd drf-channels-oneway-ws
• pipenv install --dev

Running tests

• pipenv run pytest --cov

License

This project is licensed under the MIT License.