refactor(connector.py): rewrite Connector to use selectors

This commit is contained in:
2025-09-23 23:35:09 +02:00
parent 8646388851
commit 53912ed339

View File

@@ -2,6 +2,7 @@
from __future__ import annotations
import logging as lg
import selectors
import socket
import time
from typing import Callable
@@ -16,8 +17,6 @@ class Connector:
host: str,
port: int,
*,
connect_timeout: float = 5.0,
ack_timeout: float | None = None,
on_message: Callable[[Message], None],
) -> None:
self.logger: lg.Logger = lg.getLogger(
@@ -27,178 +26,125 @@ class Connector:
self.host: str = host
self.port: int = port
self.socket_timeout: None = None
self.connect_timeout: float = connect_timeout
self.ack_timeout: float | None = ack_timeout
self.selector = selectors.DefaultSelector()
self.socket: socket.socket = socket.socket(
socket.AF_INET, socket.SOCK_STREAM
)
self.socket.setblocking(False)
self.selector.register(
self.socket,
selectors.EVENT_READ | selectors.EVENT_WRITE,
data=None,
)
self.mac_address: str = mac_address
self.inbound_buffer: bytes = b""
self.outbound_buffer: bytes = b""
self.on_message: Callable[[Message], None] = on_message
def _send_ack(self) -> None:
self.logger.debug("[>] Sending ACK...")
try:
self.socket.sendall(Message.ack().to_bytes())
self.logger.debug("[<] ACK sent")
except socket.error as e:
self.logger.error(f"[!] Failed to send ACK: {e}")
def _check_ack(self) -> bool:
self.logger.debug("[.] Waiting for ACK...")
try:
self.socket.settimeout(self.ack_timeout)
ack: bytes = self.socket.recv(1024)
self.socket.settimeout(self.socket_timeout)
if ack == Message.ack().to_bytes():
self.logger.debug("[<] ACK received")
return True
else:
self.logger.error(f"[!] Invalid ACK received: {ack}")
except TimeoutError as e:
self.logger.error(f"[!] ACK timeout: {e}")
except socket.error as e:
self.logger.error(f"[!] Failed to receive ACK: {e}")
return False
def connect(self) -> None:
retry_interval: int = 1
connected: bool = False
while not connected:
self.logger.debug(
f"[.] Connecting to {self.host}:{self.port} with timeout {self.connect_timeout}s..."
)
def _send_outbound(self) -> None:
while self.outbound_buffer:
try:
self.socket.settimeout(self.connect_timeout)
self.socket.connect((self.host, self.port))
self.socket.settimeout(self.socket_timeout)
self.logger.info(f"[+] Connected to {self.host}:{self.port}")
self.send_hello()
connected = True
except (
socket.timeout,
ConnectionRefusedError,
ConnectionAbortedError,
) as e:
self.logger.error(
f"[!] Connection to {self.host}:{self.port} failed: {e}"
sent = self.socket.send(self.outbound_buffer)
self.logger.debug(
f"[>] Sent {sent} bytes: {self.outbound_buffer[:sent]!r}"
)
self.logger.info(
f"[.] Retrying connection in {retry_interval} s..."
)
time.sleep(retry_interval)
retry_interval = min(
retry_interval * 2, 30
) # exponential backoff
self.outbound_buffer = self.outbound_buffer[sent:]
except BlockingIOError:
# OS buffer full, wait for next EVENT_WRITE
break
except socket.error as e:
self.logger.error(f"[!] Socket error: {e}")
self.reconnect()
break
def send(self, data: bytes, no_check_ack: bool = False) -> None:
self.logger.debug(f"[>] Sending data: {data}")
while True:
try:
self.socket.sendall(data)
if no_check_ack:
self.logger.debug("[>] Data sent without ACK check")
break
else:
self.logger.info("[>] Data sent")
acknowledged: bool = self._check_ack()
if acknowledged:
self.logger.debug("[.] Data acknowledged")
break
else:
self.logger.warning(
"[!] Data not acknowledged, retrying..."
)
except BrokenPipeError as e:
self.logger.error(f"[!] Broken pipe: {e}")
self.logger.info("[.] Reconnecting...")
self.connect()
except (socket.error, ValueError) as e:
self.logger.error(f"[!] Failed to send data: {e}")
time.sleep(1)
def receive(self) -> bytes:
self.logger.debug("[.] Waiting to receive data...")
def _receive_inbound(self) -> None:
try:
data: bytes = self.socket.recv(4096)
if not data:
self.logger.warning("[!] Received empty message")
return b""
self.logger.debug(f"[<] Received data: {data}")
return data
if data:
self.logger.debug(f"[<] Received {len(data)} bytes: {data!r}")
self.inbound_buffer += data
else:
self.logger.debug("[!] Connection closed by the server.")
self.reconnect()
except socket.error as e:
self.logger.error(f"[!] Failed to receive data: {e}")
return b""
def close(self) -> None:
self.logger.debug("Closing connection...")
self.socket.close()
self.logger.info("Connection closed.")
def reconnect(self) -> None:
self.logger.debug("Reconnecting...")
self.close()
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.connect()
self.logger.error(f"[!] Socket error: {e}")
self.reconnect()
def send_hello(self) -> None:
self.logger.debug("[.] Sending hello message...")
hello_message: Message = Message.hello(self.mac_address)
acknowledged: bool = False
while not acknowledged:
self.send(hello_message.to_bytes(), no_check_ack=True)
self.logger.debug("[.] Hello message sent, waiting for ACK...")
acknowledged = self._check_ack()
if not acknowledged:
self.logger.warning(
"[!] Hello message not acknowledged, retrying..."
)
time.sleep(1)
self.logger.debug("[*] Sending HELLO message...")
hello_message: bytes = Message.hello(self.mac_address).to_bytes()
self.outbound_buffer += hello_message
self._send_outbound()
def _loop(self) -> None:
self.logger.debug("Starting connector loop...")
while True:
time.sleep(0.1)
data: bytes = self.receive()
if not data:
self.reconnect()
continue
for line in data.split(b"\n"):
line: bytes = line.strip()
def close(self) -> None:
self.logger.debug("[*] Closing connection...")
self.selector.unregister(self.socket)
self.socket.close()
self.logger.debug("[.] Connection closed.")
if not line:
continue
def reconnect(self) -> None:
self.logger.debug("[*] Reconnecting...")
self.close()
self.logger.debug(f"[.] Raw message data: {line}")
try:
message: Message = Message.from_bytes(line)
except ValueError as e:
self.logger.error(f"[!] Failed to parse message: {e}")
continue
self.logger.info(f"[*] Message received: {message}")
self.on_message(message)
# reinit socket
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.socket.setblocking(False)
self.selector.register(
self.socket,
selectors.EVENT_READ | selectors.EVENT_WRITE,
data=None,
)
self.connect()
# if self._check_ack():
# self.logger.debug("[.] ACK verified")
# else:
# self.logger.error("[!] ACK verification failed")
def connect(self) -> None:
self.logger.debug(f"Connecting to {self.host}:{self.port}...")
connected: bool = False
delay: float = 1.0
while not connected:
try:
self.socket.connect((self.host, self.port))
connected = True
except BlockingIOError:
# Connection in progress
time.sleep(0.1)
except socket.error as e:
self.logger.error(f"[!] Connection error: {e}")
self.logger.debug(f"[.] Retrying in {delay} seconds...")
time.sleep(delay)
delay = min(delay * 2, 30) # exponential backoff
self.logger.debug("[*] Connected, sending HELLO...")
self.send_hello()
def run(self) -> None:
self.logger.debug("Running Connector...")
self.connect()
try:
self.connect()
self._loop()
while True:
events = self.selector.select(timeout=1)
for key, mask in events:
if mask & selectors.EVENT_READ:
self._receive_inbound()
if mask & selectors.EVENT_WRITE:
self._send_outbound()
# Process inbound buffer for complete messages
while b"\n" in self.inbound_buffer:
message_bytes, self.inbound_buffer = (
self.inbound_buffer.split(b"\n", 1)
)
try:
message = Message.from_bytes(message_bytes)
self.on_message(message)
except Exception as e:
self.logger.error(f"[!] Failed to parse message: {e}")
time.sleep(0.1)
except KeyboardInterrupt:
self.logger.info("Interrupted by user.")
self.logger.debug("[*] Interrupted by user.")
finally:
self.close()