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 from __future__ import annotations
import logging as lg import logging as lg
import selectors
import socket import socket
import time import time
from typing import Callable from typing import Callable
@@ -16,8 +17,6 @@ class Connector:
host: str, host: str,
port: int, port: int,
*, *,
connect_timeout: float = 5.0,
ack_timeout: float | None = None,
on_message: Callable[[Message], None], on_message: Callable[[Message], None],
) -> None: ) -> None:
self.logger: lg.Logger = lg.getLogger( self.logger: lg.Logger = lg.getLogger(
@@ -27,178 +26,125 @@ class Connector:
self.host: str = host self.host: str = host
self.port: int = port 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( self.socket: socket.socket = socket.socket(
socket.AF_INET, socket.SOCK_STREAM 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.mac_address: str = mac_address
self.inbound_buffer: bytes = b""
self.outbound_buffer: bytes = b""
self.on_message: Callable[[Message], None] = on_message self.on_message: Callable[[Message], None] = on_message
def _send_ack(self) -> None: def _send_outbound(self) -> None:
self.logger.debug("[>] Sending ACK...") while self.outbound_buffer:
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..."
)
try: try:
self.socket.settimeout(self.connect_timeout) sent = self.socket.send(self.outbound_buffer)
self.socket.connect((self.host, self.port)) self.logger.debug(
self.socket.settimeout(self.socket_timeout) f"[>] Sent {sent} bytes: {self.outbound_buffer[:sent]!r}"
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}"
) )
self.logger.info( self.outbound_buffer = self.outbound_buffer[sent:]
f"[.] Retrying connection in {retry_interval} s..." except BlockingIOError:
) # OS buffer full, wait for next EVENT_WRITE
time.sleep(retry_interval) break
retry_interval = min( except socket.error as e:
retry_interval * 2, 30 self.logger.error(f"[!] Socket error: {e}")
) # exponential backoff self.reconnect()
break
def send(self, data: bytes, no_check_ack: bool = False) -> None: def _receive_inbound(self) -> 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...")
try: try:
data: bytes = self.socket.recv(4096) data: bytes = self.socket.recv(4096)
if not data: if data:
self.logger.warning("[!] Received empty message") self.logger.debug(f"[<] Received {len(data)} bytes: {data!r}")
return b"" self.inbound_buffer += data
self.logger.debug(f"[<] Received data: {data}") else:
return data self.logger.debug("[!] Connection closed by the server.")
self.reconnect()
except socket.error as e: except socket.error as e:
self.logger.error(f"[!] Failed to receive data: {e}") self.logger.error(f"[!] Socket error: {e}")
return b"" self.reconnect()
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()
def send_hello(self) -> None: def send_hello(self) -> None:
self.logger.debug("[.] Sending hello message...") self.logger.debug("[*] Sending HELLO message...")
hello_message: Message = Message.hello(self.mac_address) hello_message: bytes = Message.hello(self.mac_address).to_bytes()
acknowledged: bool = False self.outbound_buffer += hello_message
while not acknowledged: self._send_outbound()
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)
def _loop(self) -> None: def close(self) -> None:
self.logger.debug("Starting connector loop...") self.logger.debug("[*] Closing connection...")
while True: self.selector.unregister(self.socket)
time.sleep(0.1) self.socket.close()
data: bytes = self.receive() self.logger.debug("[.] Connection closed.")
if not data:
self.reconnect()
continue
for line in data.split(b"\n"):
line: bytes = line.strip()
if not line: def reconnect(self) -> None:
continue self.logger.debug("[*] Reconnecting...")
self.close()
self.logger.debug(f"[.] Raw message data: {line}") # reinit socket
try: self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
message: Message = Message.from_bytes(line) self.socket.setblocking(False)
except ValueError as e: self.selector.register(
self.logger.error(f"[!] Failed to parse message: {e}") self.socket,
continue selectors.EVENT_READ | selectors.EVENT_WRITE,
self.logger.info(f"[*] Message received: {message}") data=None,
self.on_message(message) )
self.connect()
# if self._check_ack(): def connect(self) -> None:
# self.logger.debug("[.] ACK verified") self.logger.debug(f"Connecting to {self.host}:{self.port}...")
# else: connected: bool = False
# self.logger.error("[!] ACK verification failed") 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: def run(self) -> None:
self.logger.debug("Running Connector...") self.connect()
try: try:
self.connect() while True:
self._loop() 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: except KeyboardInterrupt:
self.logger.info("Interrupted by user.") self.logger.debug("[*] Interrupted by user.")
finally: finally:
self.close() self.close()