/
websocket.py
1030 lines (867 loc) · 36.9 KB
/
websocket.py
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#!/usr/bin/env python
'''
Python WebSocket library with support for "wss://" encryption.
Copyright 2011 Joel Martin
Licensed under LGPL version 3 (see docs/LICENSE.LGPL-3)
Supports following protocol versions:
- http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07
- http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-10
- http://tools.ietf.org/html/rfc6455
You can make a cert/key with openssl using:
openssl req -new -x509 -days 365 -nodes -out self.pem -keyout self.pem
as taken from http://docs.python.org/dev/library/ssl.html#certificates
'''
import os, sys, time, errno, signal, socket, select, logging
import array, struct
from base64 import b64encode, b64decode
# Imports that vary by python version
# python 3.0 differences
if sys.hexversion > 0x3000000:
b2s = lambda buf: buf.decode('latin_1')
s2b = lambda s: s.encode('latin_1')
s2a = lambda s: s
else:
b2s = lambda buf: buf # No-op
s2b = lambda s: s # No-op
s2a = lambda s: [ord(c) for c in s]
try: from io import StringIO
except: from cStringIO import StringIO
try: from http.server import SimpleHTTPRequestHandler
except: from SimpleHTTPServer import SimpleHTTPRequestHandler
# python 2.6 differences
try: from hashlib import sha1
except: from sha import sha as sha1
# python 2.5 differences
try:
from struct import pack, unpack_from
except:
from struct import pack
def unpack_from(fmt, buf, offset=0):
slice = buffer(buf, offset, struct.calcsize(fmt))
return struct.unpack(fmt, slice)
# Degraded functionality if these imports are missing
for mod, msg in [('numpy', 'HyBi protocol will be slower'),
('ssl', 'TLS/SSL/wss is disabled'),
('multiprocessing', 'Multi-Processing is disabled'),
('resource', 'daemonizing is disabled')]:
try:
globals()[mod] = __import__(mod)
except ImportError:
globals()[mod] = None
print("WARNING: no '%s' module, %s" % (mod, msg))
if multiprocessing and sys.platform == 'win32':
# make sockets pickle-able/inheritable
import multiprocessing.reduction
# HTTP handler with WebSocket upgrade support
class WebSocketRequestHandler(SimpleHTTPRequestHandler):
"""
WebSocket Request Handler Class, derived from SimpleHTTPRequestHandler.
Must be sub-classed with new_websocket_client method definition.
The request handler can be configured by setting optional
attributes on the server object:
* only_upgrade: If true, SimpleHTTPRequestHandler will not be enabled,
only websocket is allowed.
* verbose: If true, verbose logging is activated.
* daemon: Running as daemon, do not write to console etc
* record: Record raw frame data as JavaScript array into specified filename
* run_once: Handle a single request
* handler_id: A sequence number for this connection, appended to record filename
"""
buffer_size = 65536
GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
server_version = "WebSockify"
protocol_version = "HTTP/1.1"
# An exception while the WebSocket client was connected
class CClose(Exception):
pass
def __init__(self, req, addr, server):
# Retrieve a few configuration variables from the server
self.only_upgrade = getattr(server, "only_upgrade", False)
self.verbose = getattr(server, "verbose", False)
self.daemon = getattr(server, "daemon", False)
self.record = getattr(server, "record", False)
self.run_once = getattr(server, "run_once", False)
self.rec = None
self.handler_id = getattr(server, "handler_id", False)
self.file_only = getattr(server, "file_only", False)
self.traffic = getattr(server, "traffic", False)
self.logger = getattr(server, "logger", None)
if self.logger is None:
self.logger = WebSocketServer.get_logger()
SimpleHTTPRequestHandler.__init__(self, req, addr, server)
@staticmethod
def unmask(buf, hlen, plen):
pstart = hlen + 4
pend = pstart + plen
if numpy:
b = c = s2b('')
if plen >= 4:
mask = numpy.frombuffer(buf, dtype=numpy.dtype('<u4'),
offset=hlen, count=1)
data = numpy.frombuffer(buf, dtype=numpy.dtype('<u4'),
offset=pstart, count=int(plen / 4))
#b = numpy.bitwise_xor(data, mask).data
b = numpy.bitwise_xor(data, mask).tostring()
if plen % 4:
#self.msg("Partial unmask")
mask = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
offset=hlen, count=(plen % 4))
data = numpy.frombuffer(buf, dtype=numpy.dtype('B'),
offset=pend - (plen % 4),
count=(plen % 4))
c = numpy.bitwise_xor(data, mask).tostring()
return b + c
else:
# Slower fallback
mask = buf[hlen:hlen+4]
data = array.array('B')
mask = s2a(mask)
data.fromstring(buf[pstart:pend])
for i in range(len(data)):
data[i] ^= mask[i % 4]
return data.tostring()
@staticmethod
def encode_hybi(buf, opcode, base64=False):
""" Encode a HyBi style WebSocket frame.
Optional opcode:
0x0 - continuation
0x1 - text frame (base64 encode buf)
0x2 - binary frame (use raw buf)
0x8 - connection close
0x9 - ping
0xA - pong
"""
if base64:
buf = b64encode(buf)
b1 = 0x80 | (opcode & 0x0f) # FIN + opcode
payload_len = len(buf)
if payload_len <= 125:
header = pack('>BB', b1, payload_len)
elif payload_len > 125 and payload_len < 65536:
header = pack('>BBH', b1, 126, payload_len)
elif payload_len >= 65536:
header = pack('>BBQ', b1, 127, payload_len)
#self.msg("Encoded: %s", repr(header + buf))
return header + buf, len(header), 0
@staticmethod
def decode_hybi(buf, base64=False, logger=None):
""" Decode HyBi style WebSocket packets.
Returns:
{'fin' : 0_or_1,
'opcode' : number,
'masked' : boolean,
'hlen' : header_bytes_number,
'length' : payload_bytes_number,
'payload' : decoded_buffer,
'left' : bytes_left_number,
'close_code' : number,
'close_reason' : string}
"""
f = {'fin' : 0,
'opcode' : 0,
'masked' : False,
'hlen' : 2,
'length' : 0,
'payload' : None,
'left' : 0,
'close_code' : 1000,
'close_reason' : ''}
if logger is None:
logger = WebSocketServer.get_logger()
blen = len(buf)
f['left'] = blen
if blen < f['hlen']:
return f # Incomplete frame header
b1, b2 = unpack_from(">BB", buf)
f['opcode'] = b1 & 0x0f
f['fin'] = (b1 & 0x80) >> 7
f['masked'] = (b2 & 0x80) >> 7
f['length'] = b2 & 0x7f
if f['length'] == 126:
f['hlen'] = 4
if blen < f['hlen']:
return f # Incomplete frame header
(f['length'],) = unpack_from('>xxH', buf)
elif f['length'] == 127:
f['hlen'] = 10
if blen < f['hlen']:
return f # Incomplete frame header
(f['length'],) = unpack_from('>xxQ', buf)
full_len = f['hlen'] + f['masked'] * 4 + f['length']
if blen < full_len: # Incomplete frame
return f # Incomplete frame header
# Number of bytes that are part of the next frame(s)
f['left'] = blen - full_len
# Process 1 frame
if f['masked']:
# unmask payload
f['payload'] = WebSocketRequestHandler.unmask(buf, f['hlen'],
f['length'])
else:
logger.debug("Unmasked frame: %s" % repr(buf))
f['payload'] = buf[(f['hlen'] + f['masked'] * 4):full_len]
if base64 and f['opcode'] in [1, 2]:
try:
f['payload'] = b64decode(f['payload'])
except:
logger.exception("Exception while b64decoding buffer: %s" %
(repr(buf)))
raise
if f['opcode'] == 0x08:
if f['length'] >= 2:
f['close_code'] = unpack_from(">H", f['payload'])[0]
if f['length'] > 3:
f['close_reason'] = f['payload'][2:]
return f
#
# WebSocketRequestHandler logging/output functions
#
def print_traffic(self, token="."):
""" Show traffic flow mode. """
if self.traffic:
sys.stdout.write(token)
sys.stdout.flush()
def msg(self, msg, *args, **kwargs):
""" Output message with handler_id prefix. """
prefix = "% 3d: " % self.handler_id
self.logger.log(logging.INFO, "%s%s" % (prefix, msg), *args, **kwargs)
def vmsg(self, msg, *args, **kwargs):
""" Same as msg() but as debug. """
prefix = "% 3d: " % self.handler_id
self.logger.log(logging.DEBUG, "%s%s" % (prefix, msg), *args, **kwargs)
def warn(self, msg, *args, **kwargs):
""" Same as msg() but as warning. """
prefix = "% 3d: " % self.handler_id
self.logger.log(logging.WARN, "%s%s" % (prefix, msg), *args, **kwargs)
#
# Main WebSocketRequestHandler methods
#
def send_frames(self, bufs=None):
""" Encode and send WebSocket frames. Any frames already
queued will be sent first. If buf is not set then only queued
frames will be sent. Returns the number of pending frames that
could not be fully sent. If returned pending frames is greater
than 0, then the caller should call again when the socket is
ready. """
tdelta = int(time.time()*1000) - self.start_time
if bufs:
for buf in bufs:
if self.base64:
encbuf, lenhead, lentail = self.encode_hybi(buf, opcode=1, base64=True)
else:
encbuf, lenhead, lentail = self.encode_hybi(buf, opcode=2, base64=False)
if self.rec:
self.rec.write("%s,\n" %
repr("{%s{" % tdelta
+ encbuf[lenhead:len(encbuf)-lentail]))
self.send_parts.append(encbuf)
while self.send_parts:
# Send pending frames
buf = self.send_parts.pop(0)
sent = self.request.send(buf)
if sent == len(buf):
self.print_traffic("<")
else:
self.print_traffic("<.")
self.send_parts.insert(0, buf[sent:])
break
return len(self.send_parts)
def recv_frames(self):
""" Receive and decode WebSocket frames.
Returns:
(bufs_list, closed_string)
"""
closed = False
bufs = []
tdelta = int(time.time()*1000) - self.start_time
buf = self.request.recv(self.buffer_size)
if len(buf) == 0:
closed = {'code': 1000, 'reason': "Client closed abruptly"}
return bufs, closed
if self.recv_part:
# Add partially received frames to current read buffer
buf = self.recv_part + buf
self.recv_part = None
while buf:
frame = self.decode_hybi(buf, base64=self.base64,
logger=self.logger)
#self.msg("Received buf: %s, frame: %s", repr(buf), frame)
if frame['payload'] == None:
# Incomplete/partial frame
self.print_traffic("}.")
if frame['left'] > 0:
self.recv_part = buf[-frame['left']:]
break
else:
if frame['opcode'] == 0x8: # connection close
closed = {'code': frame['close_code'],
'reason': frame['close_reason']}
break
self.print_traffic("}")
if self.rec:
start = frame['hlen']
end = frame['hlen'] + frame['length']
if frame['masked']:
recbuf = WebSocketRequestHandler.unmask(buf, frame['hlen'],
frame['length'])
else:
recbuf = buf[frame['hlen']:frame['hlen'] +
frame['length']]
self.rec.write("%s,\n" %
repr("}%s}" % tdelta + recbuf))
bufs.append(frame['payload'])
if frame['left']:
buf = buf[-frame['left']:]
else:
buf = ''
return bufs, closed
def send_close(self, code=1000, reason=''):
""" Send a WebSocket orderly close frame. """
msg = pack(">H%ds" % len(reason), code, reason)
buf, h, t = self.encode_hybi(msg, opcode=0x08, base64=False)
self.request.send(buf)
def do_websocket_handshake(self):
h = self.headers
prot = 'WebSocket-Protocol'
protocols = h.get('Sec-'+prot, h.get(prot, '')).split(',')
ver = h.get('Sec-WebSocket-Version')
if ver:
# HyBi/IETF version of the protocol
# HyBi-07 report version 7
# HyBi-08 - HyBi-12 report version 8
# HyBi-13 reports version 13
if ver in ['7', '8', '13']:
self.version = "hybi-%02d" % int(ver)
else:
self.send_error(400, "Unsupported protocol version %s" % ver)
return False
key = h['Sec-WebSocket-Key']
# Choose binary if client supports it
if 'binary' in protocols:
self.base64 = False
elif 'base64' in protocols:
self.base64 = True
else:
self.send_error(400, "Client must support 'binary' or 'base64' protocol")
return False
# Generate the hash value for the accept header
accept = b64encode(sha1(s2b(key + self.GUID)).digest())
self.send_response(101, "Switching Protocols")
self.send_header("Upgrade", "websocket")
self.send_header("Connection", "Upgrade")
self.send_header("Sec-WebSocket-Accept", b2s(accept))
if self.base64:
self.send_header("Sec-WebSocket-Protocol", "base64")
else:
self.send_header("Sec-WebSocket-Protocol", "binary")
self.end_headers()
return True
else:
self.send_error(400, "Missing Sec-WebSocket-Version header. Hixie protocols not supported.")
return False
def handle_websocket(self):
"""Upgrade a connection to Websocket, if requested. If this succeeds,
new_websocket_client() will be called. Otherwise, False is returned.
"""
if (self.headers.get('upgrade') and
self.headers.get('upgrade').lower() == 'websocket'):
if not self.do_websocket_handshake():
return False
# Indicate to server that a Websocket upgrade was done
self.server.ws_connection = True
# Initialize per client settings
self.send_parts = []
self.recv_part = None
self.start_time = int(time.time()*1000)
# client_address is empty with, say, UNIX domain sockets
client_addr = ""
is_ssl = False
try:
client_addr = self.client_address[0]
is_ssl = self.client_address[2]
except IndexError:
pass
if is_ssl:
self.stype = "SSL/TLS (wss://)"
else:
self.stype = "Plain non-SSL (ws://)"
self.log_message("%s: %s WebSocket connection" % (client_addr,
self.stype))
self.log_message("%s: Version %s, base64: '%s'" % (client_addr,
self.version, self.base64))
if self.path != '/':
self.log_message("%s: Path: '%s'" % (client_addr, self.path))
if self.record:
# Record raw frame data as JavaScript array
fname = "%s.%s" % (self.record,
self.handler_id)
self.log_message("opening record file: %s" % fname)
self.rec = open(fname, 'w+')
encoding = "binary"
if self.base64: encoding = "base64"
self.rec.write("var VNC_frame_encoding = '%s';\n"
% encoding)
self.rec.write("var VNC_frame_data = [\n")
try:
self.new_websocket_client()
except self.CClose:
# Close the client
_, exc, _ = sys.exc_info()
self.send_close(exc.args[0], exc.args[1])
return True
else:
return False
def do_GET(self):
"""Handle GET request. Calls handle_websocket(). If unsuccessful,
and web server is enabled, SimpleHTTPRequestHandler.do_GET will be called."""
if not self.handle_websocket():
if self.only_upgrade:
self.send_error(405, "Method Not Allowed")
else:
SimpleHTTPRequestHandler.do_GET(self)
def list_directory(self, path):
if self.file_only:
self.send_error(404, "No such file")
else:
return SimpleHTTPRequestHandler.list_directory(self, path)
def new_websocket_client(self):
""" Do something with a WebSockets client connection. """
raise Exception("WebSocketRequestHandler.new_websocket_client() must be overloaded")
def do_HEAD(self):
if self.only_upgrade:
self.send_error(405, "Method Not Allowed")
else:
SimpleHTTPRequestHandler.do_HEAD(self)
def finish(self):
if self.rec:
self.rec.write("'EOF'];\n")
self.rec.close()
def handle(self):
# When using run_once, we have a single process, so
# we cannot loop in BaseHTTPRequestHandler.handle; we
# must return and handle new connections
if self.run_once:
self.handle_one_request()
else:
SimpleHTTPRequestHandler.handle(self)
def log_request(self, code='-', size='-'):
if self.verbose:
SimpleHTTPRequestHandler.log_request(self, code, size)
class WebSocketServer(object):
"""
WebSockets server class.
As an alternative, the standard library SocketServer can be used
"""
policy_response = """<cross-domain-policy><allow-access-from domain="*" to-ports="*" /></cross-domain-policy>\n"""
log_prefix = "websocket"
# An exception before the WebSocket connection was established
class EClose(Exception):
pass
class Terminate(Exception):
pass
def __init__(self, RequestHandlerClass, listen_host='',
listen_port=None, source_is_ipv6=False,
verbose=False, cert='', key='', ssl_only=None,
daemon=False, record='', web='',
file_only=False,
run_once=False, timeout=0, idle_timeout=0, traffic=False,
tcp_keepalive=True, tcp_keepcnt=None, tcp_keepidle=None,
tcp_keepintvl=None):
# settings
self.RequestHandlerClass = RequestHandlerClass
self.verbose = verbose
self.listen_host = listen_host
self.listen_port = listen_port
self.prefer_ipv6 = source_is_ipv6
self.ssl_only = ssl_only
self.daemon = daemon
self.run_once = run_once
self.timeout = timeout
self.idle_timeout = idle_timeout
self.traffic = traffic
self.launch_time = time.time()
self.ws_connection = False
self.handler_id = 1
self.logger = self.get_logger()
self.tcp_keepalive = tcp_keepalive
self.tcp_keepcnt = tcp_keepcnt
self.tcp_keepidle = tcp_keepidle
self.tcp_keepintvl = tcp_keepintvl
# Make paths settings absolute
self.cert = os.path.abspath(cert)
self.key = self.web = self.record = ''
if key:
self.key = os.path.abspath(key)
if web:
self.web = os.path.abspath(web)
if record:
self.record = os.path.abspath(record)
if self.web:
os.chdir(self.web)
self.only_upgrade = not self.web
# Sanity checks
if not ssl and self.ssl_only:
raise Exception("No 'ssl' module and SSL-only specified")
if self.daemon and not resource:
raise Exception("Module 'resource' required to daemonize")
# Show configuration
self.msg("WebSocket server settings:")
self.msg(" - Listen on %s:%s",
self.listen_host, self.listen_port)
self.msg(" - Flash security policy server")
if self.web:
self.msg(" - Web server. Web root: %s", self.web)
if ssl:
if os.path.exists(self.cert):
self.msg(" - SSL/TLS support")
if self.ssl_only:
self.msg(" - Deny non-SSL/TLS connections")
else:
self.msg(" - No SSL/TLS support (no cert file)")
else:
self.msg(" - No SSL/TLS support (no 'ssl' module)")
if self.daemon:
self.msg(" - Backgrounding (daemon)")
if self.record:
self.msg(" - Recording to '%s.*'", self.record)
#
# WebSocketServer static methods
#
@staticmethod
def get_logger():
return logging.getLogger("%s.%s" % (
WebSocketServer.log_prefix,
WebSocketServer.__class__.__name__))
@staticmethod
def socket(host, port=None, connect=False, prefer_ipv6=False,
unix_socket=None, use_ssl=False, tcp_keepalive=True,
tcp_keepcnt=None, tcp_keepidle=None, tcp_keepintvl=None):
""" Resolve a host (and optional port) to an IPv4 or IPv6
address. Create a socket. Bind to it if listen is set,
otherwise connect to it. Return the socket.
"""
flags = 0
if host == '':
host = None
if connect and not (port or unix_socket):
raise Exception("Connect mode requires a port")
if use_ssl and not ssl:
raise Exception("SSL socket requested but Python SSL module not loaded.");
if not connect and use_ssl:
raise Exception("SSL only supported in connect mode (for now)")
if not connect:
flags = flags | socket.AI_PASSIVE
if not unix_socket:
addrs = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM,
socket.IPPROTO_TCP, flags)
if not addrs:
raise Exception("Could not resolve host '%s'" % host)
addrs.sort(key=lambda x: x[0])
if prefer_ipv6:
addrs.reverse()
sock = socket.socket(addrs[0][0], addrs[0][1])
if tcp_keepalive:
sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
if tcp_keepcnt:
sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPCNT,
tcp_keepcnt)
if tcp_keepidle:
sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPIDLE,
tcp_keepidle)
if tcp_keepintvl:
sock.setsockopt(socket.SOL_TCP, socket.TCP_KEEPINTVL,
tcp_keepintvl)
if connect:
sock.connect(addrs[0][4])
if use_ssl:
sock = ssl.wrap_socket(sock)
else:
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(addrs[0][4])
sock.listen(100)
else:
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
sock.connect(unix_socket)
return sock
@staticmethod
def daemonize(keepfd=None, chdir='/'):
os.umask(0)
if chdir:
os.chdir(chdir)
else:
os.chdir('/')
os.setgid(os.getgid()) # relinquish elevations
os.setuid(os.getuid()) # relinquish elevations
# Double fork to daemonize
if os.fork() > 0: os._exit(0) # Parent exits
os.setsid() # Obtain new process group
if os.fork() > 0: os._exit(0) # Parent exits
# Signal handling
signal.signal(signal.SIGTERM, signal.SIG_IGN)
signal.signal(signal.SIGINT, signal.SIG_IGN)
# Close open files
maxfd = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
if maxfd == resource.RLIM_INFINITY: maxfd = 256
for fd in reversed(range(maxfd)):
try:
if fd != keepfd:
os.close(fd)
except OSError:
_, exc, _ = sys.exc_info()
if exc.errno != errno.EBADF: raise
# Redirect I/O to /dev/null
os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdin.fileno())
os.dup2(os.open(os.devnull, os.O_RDWR), sys.stdout.fileno())
os.dup2(os.open(os.devnull, os.O_RDWR), sys.stderr.fileno())
def do_handshake(self, sock, address):
"""
do_handshake does the following:
- Peek at the first few bytes from the socket.
- If the connection is Flash policy request then answer it,
close the socket and return.
- If the connection is an HTTPS/SSL/TLS connection then SSL
wrap the socket.
- Read from the (possibly wrapped) socket.
- If we have received a HTTP GET request and the webserver
functionality is enabled, answer it, close the socket and
return.
- Assume we have a WebSockets connection, parse the client
handshake data.
- Send a WebSockets handshake server response.
- Return the socket for this WebSocket client.
"""
ready = select.select([sock], [], [], 3)[0]
if not ready:
raise self.EClose("ignoring socket not ready")
# Peek, but do not read the data so that we have a opportunity
# to SSL wrap the socket first
handshake = sock.recv(1024, socket.MSG_PEEK)
#self.msg("Handshake [%s]" % handshake)
if handshake == "":
raise self.EClose("ignoring empty handshake")
elif handshake.startswith(s2b("<policy-file-request/>")):
# Answer Flash policy request
handshake = sock.recv(1024)
sock.send(s2b(self.policy_response))
raise self.EClose("Sending flash policy response")
elif handshake[0] in ("\x16", "\x80", 22, 128):
# SSL wrap the connection
if not ssl:
raise self.EClose("SSL connection but no 'ssl' module")
if not os.path.exists(self.cert):
raise self.EClose("SSL connection but '%s' not found"
% self.cert)
retsock = None
try:
retsock = ssl.wrap_socket(
sock,
server_side=True,
certfile=self.cert,
keyfile=self.key)
except ssl.SSLError:
_, x, _ = sys.exc_info()
if x.args[0] == ssl.SSL_ERROR_EOF:
if len(x.args) > 1:
raise self.EClose(x.args[1])
else:
raise self.EClose("Got SSL_ERROR_EOF")
else:
raise
elif self.ssl_only:
raise self.EClose("non-SSL connection received but disallowed")
else:
retsock = sock
# If the address is like (host, port), we are extending it
# with a flag indicating SSL. Not many other options
# available...
if len(address) == 2:
address = (address[0], address[1], (retsock != sock))
self.RequestHandlerClass(retsock, address, self)
# Return the WebSockets socket which may be SSL wrapped
return retsock
#
# WebSocketServer logging/output functions
#
def msg(self, *args, **kwargs):
""" Output message as info """
self.logger.log(logging.INFO, *args, **kwargs)
def vmsg(self, *args, **kwargs):
""" Same as msg() but as debug. """
self.logger.log(logging.DEBUG, *args, **kwargs)
def warn(self, *args, **kwargs):
""" Same as msg() but as warning. """
self.logger.log(logging.WARN, *args, **kwargs)
#
# Events that can/should be overridden in sub-classes
#
def started(self):
""" Called after WebSockets startup """
self.vmsg("WebSockets server started")
def poll(self):
""" Run periodically while waiting for connections. """
#self.vmsg("Running poll()")
pass
def terminate(self):
raise self.Terminate()
def multiprocessing_SIGCHLD(self, sig, stack):
self.vmsg('Reaing zombies, active child count is %s', len(multiprocessing.active_children()))
def fallback_SIGCHLD(self, sig, stack):
# Reap zombies when using os.fork() (python 2.4)
self.vmsg("Got SIGCHLD, reaping zombies")
try:
result = os.waitpid(-1, os.WNOHANG)
while result[0]:
self.vmsg("Reaped child process %s" % result[0])
result = os.waitpid(-1, os.WNOHANG)
except (OSError):
pass
def do_SIGINT(self, sig, stack):
self.msg("Got SIGINT, exiting")
self.terminate()
def do_SIGTERM(self, sig, stack):
self.msg("Got SIGTERM, exiting")
self.terminate()
def top_new_client(self, startsock, address):
""" Do something with a WebSockets client connection. """
# handler process
client = None
try:
try:
client = self.do_handshake(startsock, address)
except self.EClose:
_, exc, _ = sys.exc_info()
# Connection was not a WebSockets connection
if exc.args[0]:
self.msg("%s: %s" % (address[0], exc.args[0]))
except WebSocketServer.Terminate:
raise
except Exception:
_, exc, _ = sys.exc_info()
self.msg("handler exception: %s" % str(exc))
self.vmsg("exception", exc_info=True)
finally:
if client and client != startsock:
# Close the SSL wrapped socket
# Original socket closed by caller
client.close()
def start_server(self):
"""
Daemonize if requested. Listen for for connections. Run
do_handshake() method for each connection. If the connection
is a WebSockets client then call new_websocket_client() method (which must
be overridden) for each new client connection.
"""
lsock = self.socket(self.listen_host, self.listen_port, False,
self.prefer_ipv6,
tcp_keepalive=self.tcp_keepalive,
tcp_keepcnt=self.tcp_keepcnt,
tcp_keepidle=self.tcp_keepidle,
tcp_keepintvl=self.tcp_keepintvl)
if self.daemon:
self.daemonize(keepfd=lsock.fileno(), chdir=self.web)
self.started() # Some things need to happen after daemonizing
# Allow override of signals
original_signals = {
signal.SIGINT: signal.getsignal(signal.SIGINT),
signal.SIGTERM: signal.getsignal(signal.SIGTERM),
signal.SIGCHLD: signal.getsignal(signal.SIGCHLD),
}
signal.signal(signal.SIGINT, self.do_SIGINT)
signal.signal(signal.SIGTERM, self.do_SIGTERM)
if not multiprocessing:
# os.fork() (python 2.4) child reaper
signal.signal(signal.SIGCHLD, self.fallback_SIGCHLD)
else:
# make sure that _cleanup is called when children die
# by calling active_children on SIGCHLD
signal.signal(signal.SIGCHLD, self.multiprocessing_SIGCHLD)
last_active_time = self.launch_time
try:
while True:
try:
try:
startsock = None
pid = err = 0
child_count = 0
if multiprocessing:
# Collect zombie child processes
child_count = len(multiprocessing.active_children())
time_elapsed = time.time() - self.launch_time
if self.timeout and time_elapsed > self.timeout:
self.msg('listener exit due to --timeout %s'
% self.timeout)
break
if self.idle_timeout:
idle_time = 0
if child_count == 0:
idle_time = time.time() - last_active_time
else:
idle_time = 0
last_active_time = time.time()
if idle_time > self.idle_timeout and child_count == 0:
self.msg('listener exit due to --idle-timeout %s'
% self.idle_timeout)
break
try:
self.poll()
ready = select.select([lsock], [], [], 1)[0]
if lsock in ready:
startsock, address = lsock.accept()
else:
continue
except self.Terminate:
raise
except Exception:
_, exc, _ = sys.exc_info()
if hasattr(exc, 'errno'):
err = exc.errno
elif hasattr(exc, 'args'):
err = exc.args[0]
else:
err = exc[0]
if err == errno.EINTR:
self.vmsg("Ignoring interrupted syscall")
continue
else:
raise
if self.run_once:
# Run in same process if run_once
self.top_new_client(startsock, address)
if self.ws_connection :
self.msg('%s: exiting due to --run-once'
% address[0])
break
elif multiprocessing:
self.vmsg('%s: new handler Process' % address[0])
p = multiprocessing.Process(
target=self.top_new_client,
args=(startsock, address))
p.start()
# child will not return
else:
# python 2.4
self.vmsg('%s: forking handler' % address[0])