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935from dataclasses import dataclass, asdict
from typing import Optional
import urllib.parse
import logging
import json
import time
import os
import pickle
import base64
import hashlib
import uuid
import asyncio
from aiortc import RTCDataChannel, RTCPeerConnection, RTCSessionDescription
from supabase import acreate_client, AsyncClient
from realtime import AsyncRealtimeChannel
RELAY_BUFFER_SIZE = 4096
BOOTSTRAP_LABEL = 'bootstrap'
TRANSPORT_LABEL = 'transport'
logger = logging.getLogger('tunnel')
class ProxyPeer:
''' proxy peer base class '''
peer_id: str = None
async def start(self):
pass
async def stop(self):
pass
def connected(self):
return True
async def recover(self):
pass
async def do_request(self, req: 'LocalRequest', timeout: int = 60):
pass
@dataclass
class TransferData:
''' relay data with tid send/receive through one channel '''
''' mux multiple tcp connections through one data channel '''
tid: int
data: bytes
@classmethod
def from_bytes(cls, data: bytes):
pickled = pickle.loads(data)
return cls(pickled.tid, pickled.data)
def to_bytes(self):
return pickle.dumps(self)
@dataclass
class LocalRequest:
''' request send to event loop '''
method: str = None
"The type of the event"
uri: Optional[str] = None
"request uri"
tid: str = str(uuid.uuid1())
"transaction id"
reader: Optional[asyncio.StreamReader] = None
writer: Optional[asyncio.StreamWriter] = None
future: Optional[asyncio.Future] = None
@dataclass
class ChannelMessage:
''' message over supabase realtime '''
id: Optional[str] = None
'sender id, auto increment'
type: Optional[str] = None
'message type'
content: Optional[dict] = None
'message content'
timestamp: Optional[str] = None
'message timestamp'
sender: Optional[str] = None
'sender display name'
def asdict(self) -> dict:
self_dict = asdict(self)
return {k: v for k, v in self_dict.items() if v is not None}
@classmethod
def fromdict(cls, d: dict):
return cls(**d)
@dataclass
class ChannelCommand:
''' rpc request/response over supabase realtime or data channel '''
tid: Optional[str] = None
'transaction id, none for response'
method: Optional[str] = None
'rpc method name, none for response'
body: Optional[str] = None
'rpc request/response content'
error: Optional[str] = None
'rpc response error'
future: Optional[asyncio.Future] = None
'rpc request future holder, not serialized'
def asdict(self) -> dict:
self_dict = {
'tid': self.tid,
'method': self.method,
'body': self.body,
'error': self.error,
}
return {k: v for k, v in self_dict.items() if v is not None}
@classmethod
def fromdict(cls, d: dict):
return cls(**d)
def to_json(self) -> str:
return json.dumps(self.asdict())
@classmethod
def from_json(cls, json_str: str):
self_dict = json.loads(json_str)
return cls(**self_dict)
class DataChannelPair:
''' A pair of data channels '''
''' when in relay mode, sender and receiver are different '''
''' in p2p mode, sender and receiver are the same '''
def __init__(self,
signal_sid: str,
local_sid: str,
remote_sid: str,
sender: RTCDataChannel,
receiver: RTCDataChannel):
''' signal_sid mark this pair owned by which signal session '''
self.signal_sid = signal_sid
self.local_sid = local_sid
self.remote_sid = remote_sid
self.sender = sender
self.receiver = receiver
if not sender or not receiver:
self.close()
return
@sender.on('close')
def on_sender_close():
log(self.signal_sid, f'dc {self.sender.label} sender close')
receiver.close()
@receiver.on('close')
def on_receiver_close():
log(self.signal_sid, f'dc {self.sender.label} receiver close')
sender.close()
@classmethod
def new_p2p(cls, sid, dc: RTCDataChannel):
''' create a p2p pair with same sender and receiver '''
return cls(sid, sid, sid, dc, dc)
def get_label(self):
return self.receiver.label
def create_pair(self, sender: RTCDataChannel, receiver: RTCDataChannel):
return DataChannelPair(self.signal_sid, self.local_sid, self.remote_sid, sender, receiver)
def close(self):
if self.sender:
self.sender.close()
if self.receiver:
self.receiver.close()
def is_valid(self):
return self.sender and self.receiver
def is_ready(self):
if not self.sender or not self.receiver:
return False
return self.sender.readyState == 'open' and self.receiver.readyState == 'open'
def get_pair(self):
return self.sender, self.receiver
def get_sid_pair(self):
return self.local_sid, self.remote_sid
def send(self, data):
''' send data without wrapper '''
if self.is_ready():
self.sender.send(data)
def transfer(self, tid, data):
''' transfer data with tid '''
if self.is_ready():
transfer_data = TransferData(tid, data)
dumps = transfer_data.to_bytes()
self.sender.send(dumps)
def log(trace_tag: str, msg: str):
logger.info(msg=f'{trace_tag} {msg}')
def _reject(request: LocalRequest, msg: str = 'Not ready'):
if request.writer:
request.writer.write(f'HTTP/1.1 500 {msg}\r\n\r\n'.encode())
safe_close(request.writer)
log(f'{request.tid} {request.uri}', f'rejected: {msg}')
async def safe_close_peer(pc: 'RTCPeerConnection'):
try:
if pc:
await pc.close()
except Exception:
pass
def safe_close(writer: asyncio.StreamWriter):
''' Safely close a StreamWriter '''
try:
if writer and not writer.is_closing():
writer.close()
except Exception:
pass
async def safe_write(writer: asyncio.StreamWriter, data: bytes):
''' Safely write data to a StreamWriter '''
try:
if writer and len(data) and not writer.is_closing():
writer.write(data)
await writer.drain()
except Exception:
print('safe_write error')
safe_close(writer)
async def safe_write_buffers(writer: asyncio.StreamWriter, buffers: list[bytes]):
''' Safely write all buffers to a StreamWriter '''
if not writer or writer.is_closing():
return
try:
for b in buffers:
writer.write(b)
await writer.drain()
buffers.clear()
except Exception:
print('safe_write_buffers error')
safe_close(writer)
async def relay_reader_to_dc(reader: asyncio.StreamReader, pair: DataChannelPair, tid: str = None):
''' Relay data from StreamReader to DataChannel '''
while not reader.at_eof():
if (pair.sender.bufferedAmount > RELAY_BUFFER_SIZE * 100):
await asyncio.sleep(1)
continue
data = await reader.read(RELAY_BUFFER_SIZE)
if not data:
break
if tid:
pair.transfer(tid, data)
else:
pair.send(data)
log(pair.signal_sid, f'dc {pair.get_label()} relays done')
class RealtimePeer(ProxyPeer):
''' A peer that uses supabase realtime as signaling server '''
def __init__(self):
self._queue: asyncio.Queue = asyncio.Queue()
self._outgoing_requests: dict[str, ChannelCommand] = {}
self.peer_id = str(uuid.uuid1())
self.client: AsyncClient = None
self.channel: AsyncRealtimeChannel = None
self.peers: dict[str, RTCPeerConnection] = {}
self._peers_lock = asyncio.Lock()
async def relay_server_handler(self, transport: DataChannelPair, netloc: str, tid: str = None):
writer = None
try:
host, port = netloc.split(':')
if not host or not port:
raise RuntimeError('invalid label')
buffers = bytearray()
@transport.receiver.on('message')
def on_message(msg):
if isinstance(msg, str):
return
if tid is None:
if writer is None:
buffers.extend(msg)
else:
asyncio.ensure_future(safe_write(writer, msg))
return
else:
tdata = TransferData.from_bytes(msg)
if tdata.tid == tid:
asyncio.ensure_future(safe_write(writer, tdata.data))
reader, writer = await asyncio.open_connection(host, port)
log(transport.signal_sid, f'dc {transport.get_label()} connected to {host}:{port}')
await safe_write(writer, buffers)
await relay_reader_to_dc(reader, transport)
except Exception:
pass
finally:
transport.close()
safe_close(writer)
''' Create a new RTCPeerConnection with a bootstrap DataChannel '''
async def create_peer(self, peer_id: str, opened=None, closed=None):
await safe_close_peer(self.peers.get(peer_id, None))
log(peer_id, f'create new peer')
self.peers[peer_id] = pc = RTCPeerConnection()
@pc.on('connectionstatechange')
def on_connection_state():
log(peer_id, f'{pc.connectionState}')
if pc.connectionState == 'failed':
asyncio.ensure_future(safe_close_peer(pc))
elif pc.connectionState == 'closed':
self.peers.pop(peer_id, None)
def on_open():
log(peer_id, f'dc bootstrap opened')
if opened:
opened()
def on_close():
log(peer_id, f'dc bootstrap closed')
self.peers.pop(peer_id, None)
if closed:
closed()
dc = pc.createDataChannel(BOOTSTRAP_LABEL)
dc.once('open', on_open)
dc.once('close', on_close)
await pc.setLocalDescription(await pc.createOffer())
return pc
async def new_server_peer(self, req: ChannelCommand):
pc = await self.create_peer(req.tid)
@pc.on('datachannel')
def on_datachannel(dc: RTCDataChannel):
if dc.label == BOOTSTRAP_LABEL:
return
p2p_transport = DataChannelPair.new_p2p(req.tid, dc)
asyncio.create_task(self.relay_server_handler(p2p_transport, dc.label))
res = ChannelCommand(req.tid, body={
'ice': [],
'answer': pc.localDescription.sdp.replace('a=setup:actpass', 'a=setup:active')
})
await pc.setRemoteDescription(RTCSessionDescription(
req.body['offer'].replace('a=setup:actpass', 'a=setup:passive'), 'answer'))
return res
async def handle_channel_request(self, req: ChannelCommand):
if req.method == 'ping':
await self.send_channel_command(ChannelCommand(req.tid, body='pong'))
elif req.method == 'connect':
# TODO handle new peer request in random delay
res = await self.new_server_peer(req)
await self.send_channel_command(res)
def _recv_channel_command(self, msg):
try:
channelMessage = ChannelMessage.fromdict(msg['payload'])
if self.peer_id == channelMessage.id:
# command from self, ignore
return
cmd: ChannelCommand = ChannelCommand.fromdict(channelMessage.content)
if not cmd.tid:
log(self.peer_id, f'invalid command no tid {cmd}')
return
if cmd.tid in self._outgoing_requests:
log(cmd.tid, f'recv res {cmd}')
# get response from other peer
req = self._outgoing_requests.pop(cmd.tid)
if req and req.future and not req.future.done():
req.future.set_result(cmd)
return
# handle incoming request
asyncio.ensure_future(self.handle_channel_request(cmd))
except Exception as e:
log(self.peer_id, f'handle incoming message error {e}')
async def send_channel_command(self, req: ChannelCommand, timeout: int = 30):
if req is None:
return
if not self.connected():
req.future.set_exception(Exception('channel not ready'))
return
msg = ChannelMessage(self.peer_id, 'command', req.asdict(), str(time.time()))
await self.channel.send_broadcast('command', msg.asdict())
async def channel_request(self, req: ChannelCommand, timeout: int = 30) -> ChannelCommand:
if not req.tid:
req.tid = str(uuid.uuid1())
self._outgoing_requests[req.tid] = req
req.future = asyncio.Future()
try:
await self.send_channel_command(req)
await asyncio.wait_for(req.future, timeout)
return req.future.result()
except Exception as e:
log(self.peer_id, f'channel request error {e.__class__.__name__} {e}')
return None
finally:
self._outgoing_requests.pop(req.tid, None)
async def new_transport(self, req: LocalRequest):
return await self.new_client_peer(req)
async def new_client_peer(self, req: LocalRequest):
tid = req.tid
peer_id = self.peer_id
def on_open():
def on_new_dc_open():
log(tid, f'dc {new_dc.label} opened')
if req.future.done():
return
req.future.set_result(DataChannelPair.new_p2p(tid, new_dc))
new_dc = peer.createDataChannel(req.uri)
new_dc.once('open', on_new_dc_open)
def on_close():
if not req.future.done():
req.future.set_exception(Exception('peer closed'))
peer: RTCPeerConnection = self.peers.get(peer_id, None)
if peer:
if peer.connectionState == 'connected':
on_open()
elif not req.future.done():
req.future.set_exception(Exception(f'peer state {peer.connectionState}'))
return
# create new peer connection
peer = await self.create_peer(peer_id, opened=on_open, closed=on_close)
res = await self.channel_request(ChannelCommand(method='connect', body={
'offer': peer.localDescription.sdp, 'ice': []
}))
if not res:
req.future.set_result(None)
log(tid, f'channel request had no response, close peer')
await safe_close_peer(peer)
return
if res.error:
req.future.set_exception(Exception(res.error))
log(tid, f'channel request error {res.error}, close peer')
await safe_close_peer(peer)
return
if not res.body or 'answer' not in res.body:
req.future.set_exception(Exception('invalid response'))
log(tid, f'channel request had invalid response, close peer')
await safe_close_peer(peer)
return
await peer.setRemoteDescription(RTCSessionDescription(res.body['answer'], 'answer'))
async def ping_test(self, req: LocalRequest):
res = await self.channel_request(ChannelCommand(method='ping'), 10)
req.future.set_result(res.body if res else 'no response')
log(self.peer_id, f'ping test result {res}')
async def handle_http(self, req: LocalRequest):
headers = await req.reader.readuntil(b'\r\n\r\n')
netloc = req.uri
if (req.uri.startswith('http://')):
url = urllib.parse.urlparse(req.uri)
netloc = f'{url.hostname}:{url.port or 80}'
transport_req = LocalRequest('transport', netloc, req.tid)
transport: DataChannelPair = await self.do_request(transport_req)
if not transport or not transport.is_ready():
log(self.peer_id, f'transport not ready {req.uri}')
_reject(req)
return
@transport.receiver.on('message')
def on_message(msg):
if isinstance(msg, str):
return
asyncio.ensure_future(safe_write(req.writer, msg))
@transport.receiver.on('close')
def on_close():
safe_close(req.writer)
try:
if req.method == 'CONNECT':
http200 = b'HTTP/1.1 200 Connection established\r\n\r\n'
asyncio.ensure_future(safe_write(req.writer, http200))
else:
req_line = f'{req.method} {req.uri} HTTP/1.1\r\n'.encode()
transport.send(req_line)
transport.send(headers)
await relay_reader_to_dc(req.reader, transport)
finally:
transport.close()
# make request done
if not req.future.done():
req.future.set_result(None)
async def start_event_loop(self):
log(self.peer_id, f'eventloop start')
try:
req: LocalRequest
while True:
req = await self._queue.get()
if req.method == 'transport':
asyncio.create_task(self.new_transport(req))
elif req.method == 'ping':
asyncio.create_task(self.ping_test(req))
elif req.method == 'close':
break
else:
asyncio.create_task(self.handle_http(req))
log(self.peer_id, f'eventloop exit')
except Exception as e:
log(self.peer_id, f'eventloop error: {e}')
async def do_request(self, req: LocalRequest, timeout: int = 60):
trace_tag = f'{req.tid} {req.uri}'
req.future = asyncio.Future()
self._queue.put_nowait(req)
try:
await asyncio.wait_for(req.future, timeout)
return req.future.result()
except Exception as e:
log(trace_tag, f'dc {req.method} error {e.__class__.__name__} {e}')
return None
async def init_channel(self):
hostname = os.environ.get('HOSTNAME', 'Realtime Peer')
signal_room = os.environ.get('SIGNAL_ROOM', 'default')
supabase_key = os.environ.get('SUPABASE_KEY', '')
supabase_url = os.environ.get('SUPABASE_URL', '')
self.client = await acreate_client(supabase_url, supabase_key)
self.channel = self.client.channel(f'room:{signal_room}:messages')
self.channel.on_broadcast('command', self._recv_channel_command)
await self.channel.subscribe()
await self.channel.track({
'id': self.peer_id,
'name': hostname,
})
async def recover(self):
if self.client and not self.client.get_channels():
await self.init_channel()
def connected(self):
return self.channel and self.channel.is_joined
async def start(self):
if self.client:
return
await self.init_channel()
asyncio.create_task(self.start_event_loop())
async def stop(self):
if self.client:
await self.client.remove_all_channels()
self._queue.put_nowait(LocalRequest('close'))
await asyncio.gather(*[peer.close() for peer in self.peers.values()])
class HttpPeer(ProxyPeer):
''' http peer, use OPTIONS as CONNECT request '''
WS_MAGIC = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
CF_HTTPS_PORTS = (443,2053,2083,2087,2096,8443)
def __init__(self):
self.endpoint_cname = self._get_endpoint_cname()
self.peer_id = str(uuid.uuid1())
self.https_port_idx = 0
def _get_endpoint_cname(self):
endpoint_domain = os.environ.get('ENDPOINT_DOMAIN', None)
''' get endpoint domain cname '''
if not endpoint_domain:
return None
# request dns cname
try:
import dns.resolver
answers = dns.resolver.resolve(endpoint_domain, 'CNAME', raise_on_no_answer=False)
for r in answers:
cname = str(r.target).rstrip('.')
log('', f'get_endpoint_cname(dnspython) {cname}')
return cname
except Exception:
return None
async def relay_tcp_to_ws(self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter, tag: str):
''' Relay data from StreamReader to ws StreamWriter '''
while not reader.at_eof():
payload = await reader.read(RELAY_BUFFER_SIZE)
if not payload:
break
payload_len = len(payload)
frame = bytearray()
frame.append(0x80 | 0x02)
if payload_len < 126:
frame.append(payload_len)
elif payload_len <= 0xFFFF:
frame.append(126)
frame.extend(payload_len.to_bytes(2, 'big'))
else:
frame.append(127)
frame.extend(payload_len.to_bytes(8, 'big'))
frame.extend(payload)
# log(tag, f'tcp->ws write {payload_len} bytes {len(payload)}')
await safe_write(writer, bytes(frame))
safe_close(writer)
log(tag, 'tcp->ws relays done')
async def safe_ws_to_tcp(self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter, tag: str):
try:
await self.relay_ws_to_tcp(reader, writer, tag)
except Exception as e:
log(tag, f'ws->tcp relay error {e}')
async def safe_tcp_to_ws(self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter, tag: str):
try:
await self.relay_tcp_to_ws(reader, writer, tag)
except Exception as e:
log(tag, f'tcp->ws relay error {e}')
async def relay_ws_to_tcp(self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter, tag: str):
''' Relay data from ws StreamReader to StreamWriter '''
# Support both text (opcode 0x1) and binary (opcode 0x2) frames
while True:
data = await reader.read(2)
if not data:
break
fin_opcode = data[0]
opcode = fin_opcode & 0x0F
mask = (data[1] >> 7) & 0x01
payload_len = data[1] & 127
if payload_len == 126:
ext = await reader.read(2)
payload_len = int.from_bytes(ext, 'big')
elif payload_len == 127:
ext = await reader.read(8)
payload_len = int.from_bytes(ext, 'big')
payload = bytearray()
if mask:
mask_key = await reader.read(4)
encoded = await reader.read(payload_len)
payload.extend(bytes(b ^ mask_key[i % 4] for i, b in enumerate(encoded)))
else:
payload.extend(await reader.read(payload_len))
while len(payload) < payload_len:
payload.extend(await reader.read(payload_len - len(payload)))
if (len(payload) < payload_len):
log(tag, f'ws->tcp read incomplete payload {len(payload)}/{payload_len}')
break
# Only relay text or binary frames
if opcode in (0x01, 0x02):
# log(tag, f'ws->tcp write {payload_len} bytes {len(payload)}')
await safe_write(writer, payload)
safe_close(writer)
log(tag, 'ws->tcp relays done')
async def do_connect(self, req: LocalRequest, timeout):
trace_tag = f'{req.tid} {req.uri}'
reader, writer = None, None
self.https_port_idx = 0 if self.https_port_idx >= len(self.CF_HTTPS_PORTS) - 1 else self.https_port_idx + 1
https_port = self.CF_HTTPS_PORTS[self.https_port_idx]
try:
# ignore all headers
await asyncio.wait_for(req.reader.readuntil(b'\r\n\r\n'), timeout=timeout)
# open connection to remote http endpoint
reader, writer = await asyncio.open_connection(self.endpoint_cname, https_port, ssl=True)
log(trace_tag, f'connected to {self.endpoint_cname}:{https_port}')
# relay connect request to remote endpoint
req_headers = (
f'GET /connect/{req.uri} HTTP/1.1\r\n'
f'Host: {self.endpoint_cname}\r\n'
f"Sec-WebSocket-Key: SGVsbG8sIHdvcmxkIQ==\r\n"
f"Sec-WebSocket-Version: 13\r\n"
f'Connection: upgrade\r\n'
f'Upgrade: websocket\r\n\r\n'
)
await safe_write(writer, req_headers.encode())
http101 = await asyncio.wait_for(reader.readuntil(b'\r\n\r\n'), 10)
if not http101.decode().startswith('HTTP/1.1 101'):
_reject(req, 'Server failed')
safe_close(writer)
self.endpoint_cname = self._get_endpoint_cname()
return
# remote connect success, reply http200 to client
http200 = b'HTTP/1.1 200 Connection established\r\n\r\n'
await safe_write(req.writer, http200)
asyncio.ensure_future(self.safe_tcp_to_ws(req.reader, writer, trace_tag))
await self.safe_ws_to_tcp(reader, req.writer, trace_tag)
except Exception as e:
log(trace_tag, f'request CONNECT failed: {e}')
self.endpoint_cname = self._get_endpoint_cname()
_reject(req, 'Connection failed')
safe_close(writer)
async def ws_accept(self, req: LocalRequest, headers: bytes):
# parse websocket key from headers, and calculate accept key
ws_key = None
header_lines = headers.decode().split(b'\r\n')
for line in header_lines:
if line.lower().startswith('sec-websocket-key:'):
ws_key = line.split(':', 1)[1].strip()
break
if not ws_key:
_reject(req, 'Invalid key')
return
sec_accept = base64.b64encode(hashlib.sha1((ws_key + self.WS_MAGIC).encode()).digest()).decode()
# reply http101 to accept ws
response = (
'HTTP/1.1 101 Switching Protocols\r\n'
'Connection: upgrade\r\n'
'Upgrade: websocket\r\n'
f'Sec-WebSocket-Accept: {sec_accept}\r\n\r\n'
)
await safe_write(req.writer, response.encode())
async def do_websocket(self, req: LocalRequest, timeout: int = 60):
trace_tag = f'{req.tid} {req.uri}'
try:
headers = await asyncio.wait_for(req.reader.readuntil(b'\r\n\r\n'), timeout=timeout)
netloc = req.uri.removeprefix('/connect/')
host, port = netloc.split(':')
if not host or not port:
_reject(req, 'Invalid host')
reader, writer = await asyncio.open_connection(host, port)
# remote connect success, reply http101 to client
self.ws_accept(req, headers)
log(trace_tag, f'connected to {host}:{port}')
asyncio.ensure_future(self.safe_ws_to_tcp(req.reader, writer, netloc))
await self.safe_tcp_to_ws(reader, req.writer, netloc)
except Exception as e:
log(trace_tag, f'request WEBSOCKET failed: {e}')
_reject(req, 'Connection failed')
async def do_request(self, req: LocalRequest, timeout: int = 10):
if req.method == 'CONNECT':
await self.do_connect(req, timeout)
elif req.method == 'GET' and req.uri.startswith('/connect/'):
await self.do_websocket(req, timeout)
else:
_reject(req, 'Not supported')
class HttpServer:
''' http proxy '''
def __init__(self, endpoint: ProxyPeer):
self.logger = logging.getLogger('http')
self.realtime_peer = endpoint
self.http_peer = HttpPeer()
self.use_realtime = False
async def handle_request(self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter):
client_addr, client_port = writer.get_extra_info('peername')
tag = f'{client_addr}:{client_port}'
self.logger.info(f'{tag} new connection')
try:
request_line = (await reader.readline()).decode()
method, uri, _ = request_line.split()
except Exception:
writer.write(b'HTTP/1.1 400 Bad Request\r\n\r\n')
safe_close(writer)
return
# switch between realtime and http peer
self.use_realtime = not self.use_realtime
peer = self.realtime_peer if self.use_realtime else self.http_peer
self.logger.info(f'{tag} received {method} {uri} by {peer.__class__.__name__}')
# endpoint readiness check
if method == 'GET' and uri == '/':
if self.realtime_peer.connected():
writer.write(b'HTTP/1.1 200 OK\r\n\r\n')
else:
await self.realtime_peer.recover()
writer.write(b'HTTP/1.1 500 Not ready\r\n\r\n')
safe_close(writer)
return
# custom testing
if method == 'GET' and uri == '/ping':
res = await self.realtime_peer.do_request(LocalRequest('ping'))
writer.write(f'HTTP/1.1 200 {res}\r\n\r\n'.encode())
safe_close(writer)
return
# proxy over websocket
if method == 'GET' and uri.startswith('/connect/'):
await self.http_peer.do_request(LocalRequest(
method,
uri,
tag,
reader,
writer
))
return
# https proxy
if method != 'CONNECT':
# http proxy, request line: GET http://host:port/path HTTP/1.1
if not uri.startswith('http://'):
writer.write(b'HTTP/1.1 400 Bad Request\r\n\r\n')
safe_close(writer)
return
if peer.connected():
try:
req = LocalRequest(
method.upper(),
uri,
tag,
reader,
writer
)
await peer.do_request(req, timeout=120)
self.logger.info(f'{tag} done {method} {uri}')
except Exception as e:
self.logger.error(f'{tag} error {method} {uri}: {e}')
writer.write(b'HTTP/1.1 500 Internal Server Error\r\n\r\n')
safe_close(writer)
else:
self.logger.info(f'{tag} rejected {method} {uri}')
writer.write(b'HTTP/1.1 500 Not ready\r\n\r\n')
safe_close(writer)
# recover peer
await peer.recover()
async def start(self, port: int = 1234):
server = await asyncio.start_server(self.handle_request, port=port)
addr = server.sockets[0].getsockname()
self.logger.info(f'Local server running on {addr[0]}:{addr[1]}')
await self.realtime_peer.start()
async with server:
await server.serve_forever()
async def stop(self):
if self.realtime_peer:
await self.realtime_peer.stop()
async def main():
process = None
try:
if '--server' in sys.argv:
process = HttpServer(RealtimePeer())
await process.start(port=8001)
else:
process = HttpServer(RealtimePeer())
await process.start(port=2234)
except KeyboardInterrupt:
pass
finally:
await process.stop()
if __name__ == '__main__':
import sys
from aioice import ice
ice.CONSENT_INTERVAL = 2
ice.CONSENT_FAILURES = 5
# Setup logging configuration
debug = '--debug' in sys.argv
logging.basicConfig(
level=logging.DEBUG if debug else logging.INFO,
format='%(asctime)s %(name)s %(levelname)s %(message)s'
)
if not debug:
logging.getLogger('realtime._async.client').setLevel(logging.WARNING)
asyncio.run(main())