87 lines
2.9 KiB
Python
87 lines
2.9 KiB
Python
import typing
|
|
import struct
|
|
import asyncio
|
|
import logging
|
|
|
|
|
|
log = logging.getLogger(__name__)
|
|
|
|
|
|
class ElasticNotifierProtocol(asyncio.Protocol):
|
|
"""notifies the reader when ES has written updates"""
|
|
|
|
def __init__(self, listeners):
|
|
self._listeners = listeners
|
|
self.transport: typing.Optional[asyncio.Transport] = None
|
|
|
|
def connection_made(self, transport):
|
|
self.transport = transport
|
|
self._listeners.append(self)
|
|
log.info("got es notifier connection")
|
|
|
|
def connection_lost(self, exc) -> None:
|
|
self._listeners.remove(self)
|
|
self.transport = None
|
|
|
|
def send_height(self, height: int, block_hash: bytes):
|
|
log.info("notify es update '%s'", height)
|
|
self.transport.write(struct.pack(b'>Q32s', height, block_hash))
|
|
|
|
|
|
class ElasticNotifierClientProtocol(asyncio.Protocol):
|
|
"""notifies the reader when ES has written updates"""
|
|
|
|
def __init__(self, notifications: asyncio.Queue, host: str, port: int):
|
|
self.notifications = notifications
|
|
self.transport: typing.Optional[asyncio.Transport] = None
|
|
self.host = host
|
|
self.port = port
|
|
self._lost_connection = asyncio.Event()
|
|
self._lost_connection.set()
|
|
|
|
async def connect(self):
|
|
if self._lost_connection.is_set():
|
|
await asyncio.get_event_loop().create_connection(
|
|
lambda: self, self.host, self.port
|
|
)
|
|
|
|
async def maintain_connection(self, synchronized: asyncio.Event):
|
|
first_connect = True
|
|
if not self._lost_connection.is_set():
|
|
synchronized.set()
|
|
while True:
|
|
try:
|
|
await self._lost_connection.wait()
|
|
if not first_connect:
|
|
log.warning("lost connection to scribe-elastic-sync notifier")
|
|
await self.connect()
|
|
first_connect = False
|
|
synchronized.set()
|
|
log.info("connected to es notifier")
|
|
except Exception as e:
|
|
if not isinstance(e, asyncio.CancelledError):
|
|
log.warning("waiting 30s for scribe-elastic-sync notifier to become available (%s:%i)", self.host, self.port)
|
|
await asyncio.sleep(30)
|
|
else:
|
|
log.info("stopping the notifier loop")
|
|
raise e
|
|
|
|
def close(self):
|
|
if self.transport and not self.transport.is_closing():
|
|
self.transport.close()
|
|
|
|
def connection_made(self, transport):
|
|
self.transport = transport
|
|
self._lost_connection.clear()
|
|
|
|
def connection_lost(self, exc) -> None:
|
|
self.transport = None
|
|
self._lost_connection.set()
|
|
|
|
def data_received(self, data: bytes) -> None:
|
|
try:
|
|
height, block_hash = struct.unpack(b'>Q32s', data)
|
|
except:
|
|
log.exception("failed to decode %s", (data or b'').hex())
|
|
raise
|
|
self.notifications.put_nowait((height, block_hash))
|