samhaque/graphene-tornado

graphene-tornado

A project for running Graphene on top of Tornado in Python 2 and 3. The codebase is a port of graphene-django.

Getting started

Create a Tornado application and add the GraphQL handlers:

import tornado.web
from tornado.ioloop import IOLoop

from graphene_tornado.schema import schema
from graphene_tornado.tornado_graphql_handler import TornadoGraphQLHandler


class ExampleApplication(tornado.web.Application):

    def __init__(self):
        handlers = [
            (r'/graphql', TornadoGraphQLHandler, dict(graphiql=True, schema=schema)),
            (r'/graphql/batch', TornadoGraphQLHandler, dict(graphiql=True, schema=schema, batch=True)),
            (r'/graphql/graphiql', TornadoGraphQLHandler, dict(graphiql=True, schema=schema))
        ]
        tornado.web.Application.__init__(self, handlers)

if __name__ == '__main__':
    app = ExampleApplication()
    app.listen(5000)
    IOLoop.instance().start()

When writing your resolvers, decorate them with either Tornado's @coroutine decorator for Python 2.7:

@gen.coroutine
def resolve_foo(self, info):
  foo = yield db.get_foo()
  raise Return(foo)

Or use the async / await pattern in Python 3:

async def resolve_foo(self, info):
  foo = await db.get_foo()
  return foo