goblin_tornado.py

from services.social_graph_api.BaseRequestHandler import BaseRequestHandler

from tornado import gen
from tornado import web

from graph.models.components.Device import Device
from graph.models.components.Event import Event
from graph.models.components.SensorStream import SensorStream

from goblin.models.element import BaseElement

class ComponentRelationsHandler(BaseRequestHandler):
	
	def prepare(self):
		super().prepare()
		self.bind_class()

	def bind_class(self):
		self.Component = Device

	@gen.coroutine
	def _get_component_by_name(self, name):
		try:
			component = yield self.Component.get(name)
			return component
		except BaseElement.DoesNotExist as e:
			raise web.HTTPError(404)

	@gen.coroutine
	def get(self, name):
		component = yield self._get_component_by_name(name)

		stream = yield component.outE()
		relations_list = []
		while True:
			resp = yield stream.read() ## Here is the problem
			if resp is None:    
				break
			relations_list += [(relation.as_dict()+{'label': relation.label()}) for relation in resp]
		self.write_json(relations_list)

	@gen.coroutine
	def delete(self, name):
		component = self._get_component_by_name(name)
		stream = yield component.outE()
		relations_list = []
		while True:
			resp = yield stream.read()
			if resp is None:
				break
			for relation in resp:
				yield relation.delete()
		self.acknowledge()

class DeviceRelationsHandler(ComponentRelationsHandler):
	def bind_class(self):
		self.Component = Device

class EventRelationsHandler(ComponentRelationsHandler):
	def bind_class(self):
		self.Component = Event

class SensorStreamRelationsHandler(ComponentRelationsHandler):
	def bind_class(self):
		self.Component = SensorStream