Skip to main content

Websocket backend for GraphQL subscriptions

Project description

Websocket backend for GraphQL subscriptions.

Supports the following application servers:

Python 3 application servers, using asyncio:

Python 2 application servers:

Installation instructions

For instaling graphql-ws, just run this command in your shell

pip install graphql-ws

Examples

Python 3 servers

Create a subscribable schema like this:

import asyncio
import graphene


class Query(graphene.ObjectType):
    hello = graphene.String()

    @staticmethod
    def resolve_hello(obj, info, **kwargs):
        return "world"


class Subscription(graphene.ObjectType):
    count_seconds = graphene.Float(up_to=graphene.Int())

    async def resolve_count_seconds(root, info, up_to):
        for i in range(up_to):
            yield i
            await asyncio.sleep(1.)
        yield up_to


schema = graphene.Schema(query=Query, subscription=Subscription)

aiohttp

Then just plug into your aiohttp server.

from graphql_ws.aiohttp import AiohttpSubscriptionServer
from .schema import schema

subscription_server = AiohttpSubscriptionServer(schema)


async def subscriptions(request):
    ws = web.WebSocketResponse(protocols=('graphql-ws',))
    await ws.prepare(request)

    await subscription_server.handle(ws)
    return ws


app = web.Application()
app.router.add_get('/subscriptions', subscriptions)

web.run_app(app, port=8000)

You can see a full example here: https://github.com/graphql-python/graphql-ws/tree/master/examples/aiohttp

websockets compatible servers

Works with any framework that uses the websockets library for its websocket implementation. For this example, plug in your Sanic server.

from graphql_ws.websockets_lib import WsLibSubscriptionServer
from . import schema

app = Sanic(__name__)

subscription_server = WsLibSubscriptionServer(schema)

@app.websocket('/subscriptions', subprotocols=['graphql-ws'])
async def subscriptions(request, ws):
    await subscription_server.handle(ws)
    return ws


app.run(host="0.0.0.0", port=8000)

Django v2+

Django Channels 2

Set up with Django Channels just takes three steps:

  1. Install the apps
  2. Set up your schema
  3. Configure the channels router application

First pip install channels and it to your INSTALLED_APPS. If you want graphiQL, install the graphql_ws.django app before graphene_django to serve a graphiQL template that will work with websockets:

INSTALLED_APPS = [
    "channels",
    "graphql_ws.django",
    "graphene_django",
    # ...
]

Point to your schema in Django settings:

GRAPHENE = {
    'SCHEMA': 'yourproject.schema.schema'
}

Finally, you can set up channels routing yourself (maybe using graphql_ws.django.routing.websocket_urlpatterns in your URLRouter), or you can just use one of the preset channels applications:

ASGI_APPLICATION = 'graphql_ws.django.routing.application'
# or
ASGI_APPLICATION = 'graphql_ws.django.routing.auth_application'

Run ./manage.py runserver and go to http://localhost:8000/graphql to test!

Python 2 servers

Create a subscribable schema like this:

import graphene
from rx import Observable


class Query(graphene.ObjectType):
    hello = graphene.String()

    @staticmethod
    def resolve_hello(obj, info, **kwargs):
        return "world"


class Subscription(graphene.ObjectType):
    count_seconds = graphene.Float(up_to=graphene.Int())

    async def resolve_count_seconds(root, info, up_to=5):
        return Observable.interval(1000)\
                         .map(lambda i: "{0}".format(i))\
                         .take_while(lambda i: int(i) <= up_to)


schema = graphene.Schema(query=Query, subscription=Subscription)

Gevent compatible servers

Then just plug into your Gevent server, for example, Flask:

from flask_sockets import Sockets
from graphql_ws.gevent import GeventSubscriptionServer
from schema import schema

subscription_server = GeventSubscriptionServer(schema)
app.app_protocol = lambda environ_path_info: 'graphql-ws'


@sockets.route('/subscriptions')
def echo_socket(ws):
    subscription_server.handle(ws)
    return []

You can see a full example here: https://github.com/graphql-python/graphql-ws/tree/master/examples/flask_gevent

Django v1.x

For Django v1.x and Django Channels v1.x, setup your schema in settings.py

GRAPHENE = {
    'SCHEMA': 'yourproject.schema.schema'
}

Then pip install "channels<1" and it to your django apps, adding the following to your settings.py

CHANNELS_WS_PROTOCOLS = ["graphql-ws", ]
CHANNEL_LAYERS = {
    "default": {
        "BACKEND": "asgiref.inmemory.ChannelLayer",
        "ROUTING": "django_subscriptions.urls.channel_routing",
    },
}

And finally add the channel routes

from channels.routing import route_class
from graphql_ws.django_channels import GraphQLSubscriptionConsumer

channel_routing = [
    route_class(GraphQLSubscriptionConsumer, path=r"^/subscriptions"),
]

You can see a full example here: https://github.com/graphql-python/graphql-ws/tree/master/examples/django_subscriptions

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

graphql-ws-0.4.4.tar.gz (47.9 kB view hashes)

Uploaded source

Built Distribution

graphql_ws-0.4.4-py2.py3-none-any.whl (17.3 kB view hashes)

Uploaded py2 py3

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Huawei Huawei PSF Sponsor Microsoft Microsoft PSF Sponsor NVIDIA NVIDIA PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page