py-libp2p/libp2p/tools/pubsub/dummy_account_node.py
Jonathan de Jong b1248ff315 enforced f-strings everywhere, %s on logging
extended _multiaddr_from_socket to support UDP and IPv6 automatically
changed TCPListener to use _ip4_or_6_from_multiaddr to get host, and not ip4 only

enforced `from error` everywhere with raises
added call braces to exceptions
2019-12-19 17:31:18 +01:00

136 lines
4.5 KiB
Python

import asyncio
from typing import Dict
import uuid
from libp2p.host.host_interface import IHost
from libp2p.pubsub.floodsub import FloodSub
from libp2p.pubsub.pubsub import Pubsub
from libp2p.tools.constants import LISTEN_MADDR
from libp2p.tools.factories import FloodsubFactory, PubsubFactory
CRYPTO_TOPIC = "ethereum"
# Message format:
# Sending crypto: <source>,<dest>,<amount as integer>
# Ex. send,aspyn,alex,5
# Set crypto: <dest>,<amount as integer>
# Ex. set,rob,5
# Determine message type by looking at first item before first comma
class DummyAccountNode:
"""
Node which has an internal balance mapping, meant to serve as a dummy
crypto blockchain.
There is no actual blockchain, just a simple map indicating how much
crypto each user in the mappings holds
"""
libp2p_node: IHost
pubsub: Pubsub
floodsub: FloodSub
def __init__(self, libp2p_node: IHost, pubsub: Pubsub, floodsub: FloodSub):
self.libp2p_node = libp2p_node
self.pubsub = pubsub
self.floodsub = floodsub
self.balances: Dict[str, int] = {}
self.node_id = str(uuid.uuid1())
@classmethod
async def create(cls) -> "DummyAccountNode":
"""
Create a new DummyAccountNode and attach a libp2p node, a floodsub, and
a pubsub instance to this new node.
We use create as this serves as a factory function and allows us
to use async await, unlike the init function
"""
pubsub = PubsubFactory(router=FloodsubFactory())
await pubsub.host.get_network().listen(LISTEN_MADDR)
return cls(libp2p_node=pubsub.host, pubsub=pubsub, floodsub=pubsub.router)
async def handle_incoming_msgs(self) -> None:
"""Handle all incoming messages on the CRYPTO_TOPIC from peers."""
while True:
incoming = await self.q.get()
msg_comps = incoming.data.decode("utf-8").split(",")
if msg_comps[0] == "send":
self.handle_send_crypto(msg_comps[1], msg_comps[2], int(msg_comps[3]))
elif msg_comps[0] == "set":
self.handle_set_crypto(msg_comps[1], int(msg_comps[2]))
async def setup_crypto_networking(self) -> None:
"""Subscribe to CRYPTO_TOPIC and perform call to function that handles
all incoming messages on said topic."""
self.q = await self.pubsub.subscribe(CRYPTO_TOPIC)
asyncio.ensure_future(self.handle_incoming_msgs())
async def publish_send_crypto(
self, source_user: str, dest_user: str, amount: int
) -> None:
"""
Create a send crypto message and publish that message to all other
nodes.
:param source_user: user to send crypto from
:param dest_user: user to send crypto to
:param amount: amount of crypto to send
"""
msg_contents = f"send,{source_user},{dest_user},{amount!s}"
await self.pubsub.publish(CRYPTO_TOPIC, msg_contents.encode())
async def publish_set_crypto(self, user: str, amount: int) -> None:
"""
Create a set crypto message and publish that message to all other
nodes.
:param user: user to set crypto for
:param amount: amount of crypto
"""
msg_contents = f"set,{user},{amount!s}"
await self.pubsub.publish(CRYPTO_TOPIC, msg_contents.encode())
def handle_send_crypto(self, source_user: str, dest_user: str, amount: int) -> None:
"""
Handle incoming send_crypto message.
:param source_user: user to send crypto from
:param dest_user: user to send crypto to
:param amount: amount of crypto to send
"""
if source_user in self.balances:
self.balances[source_user] -= amount
else:
self.balances[source_user] = -amount
if dest_user in self.balances:
self.balances[dest_user] += amount
else:
self.balances[dest_user] = amount
def handle_set_crypto(self, dest_user: str, amount: int) -> None:
"""
Handle incoming set_crypto message.
:param dest_user: user to set crypto for
:param amount: amount of crypto
"""
self.balances[dest_user] = amount
def get_balance(self, user: str) -> int:
"""
Get balance in crypto for a particular user.
:param user: user to get balance for
:return: balance of user
"""
if user in self.balances:
return self.balances[user]
else:
return -1