data = Generators.observe(notify => {
const data = []
const socket = new WebSocket('wss://ws.blockchain.info/inv')
socket.addEventListener('open', () => socket.send(JSON.stringify({op: 'unconfirmed_sub'})))
socket.addEventListener('message', (message) => {
while (data.length && +data[0].time < new Date(Date.now() - 30000)) data.shift()
data.push({ time: new Date(), size: JSON.parse(message.data).x.size })
notify(data)
})
notify(data)
return () => socket.close()
})