"""Async sockets, build on top of Sam Rushing's excellent async library"""
import asyncore
import socket
from socket import AF_INET,SOCK_STREAM
import string
import cStringIO
import mimetools
import httplib
__version__ = "0.9"
__author__ = "jvr"
BUFSIZE = 512
VERBOSE = 1
class Server(asyncore.dispatcher):
"""Generic asynchronous server class"""
def __init__(self, port, handler_class, backlog=1, host=""):
"""arguments:
- port: the port to listen to
- handler_class: class to handle requests
- backlog: backlog queue size (optional) (don't fully understand, see socket docs)
- host: host name (optional: can be empty to use default host name)
"""
if VERBOSE:
print "Starting", self.__class__.__name__
self.handler_class = handler_class
asyncore.dispatcher.__init__(self)
self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
self.bind((host, port))
self.listen(backlog)
def handle_accept(self):
conn, addr = self.accept()
if VERBOSE:
print 'Incoming Connection from %s:%d' % addr
self.handler_class(conn)
class ProxyServer(Server):
"""Generic proxy server class"""
def __init__(self, port, handler_class, proxyaddr=None, closepartners=0):
"""arguments:
- port: the port to listen to
- handler_class: proxy class to handle requests
- proxyaddr: a tuple containing the address and
port of a remote host to connect to (optional)
- closepartners: boolean, specifies whether we should close
all proxy connections or not (optional). http seems to *not*
want this, but telnet does...
"""
Server.__init__(self, port, handler_class, 1, "")
self.proxyaddr = proxyaddr
self.closepartners = closepartners
def handle_accept(self):
conn, addr = self.accept()
if VERBOSE:
print 'Incoming Connection from %s:%d' % addr
self.handler_class(conn, self.proxyaddr, closepartner=self.closepartners)
class Connection(asyncore.dispatcher):
"""Generic connection class"""
def __init__(self, sock_or_address=None, readfunc=None, terminator=None):
"""arguments:
- sock_or_address: either a socket, or a tuple containing the name
and port number of a remote host
- readfunc: callback function (optional). Will be called whenever
there is some data available, or when an appropraite terminator
is found.
- terminator: string which specifies when a read is complete (optional)"""
self._out_buffer = ""
self._in_buffer = ""
self.readfunc = readfunc
self.terminator = terminator
asyncore.dispatcher.__init__(self)
if hasattr(sock_or_address, "fileno"):
self.set_socket(sock_or_address)
else:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setblocking(0)
self.set_socket(sock)
if sock_or_address:
self.connect(sock_or_address)
# public methods
def send(self, data):
self._out_buffer = self._out_buffer + data
def recv(self, bytes=-1):
if bytes == -1:
bytes = len(self._in_buffer)
data = self._in_buffer[:bytes]
self._in_buffer = self._in_buffer[bytes:]
return data
def set_terminator(self, terminator):
self.terminator = terminator
# override this if you want to control the incoming data stream
def handle_incoming_data(self, data):
if self.readfunc:
if self.terminator:
self._in_buffer = self._in_buffer + data
pos = string.find(self._in_buffer, self.terminator)
if pos < 0:
return
data = self._in_buffer[:pos]
self._in_buffer = self._in_buffer[pos + len(self.terminator):]
self.readfunc(data)
else:
self.readfunc(self._in_buffer + data)
self._in_buffer = ""
else:
self._in_buffer = self._in_buffer + data
# internal muck
def handle_read(self):
data = asyncore.dispatcher.recv(self, BUFSIZE)
if data:
if VERBOSE > 2:
print "incoming ->", "%x" % id(self), `data`
self.handle_incoming_data(data)
def handle_write(self):
if self._out_buffer:
sent = self.socket.send(self._out_buffer[:BUFSIZE])
if VERBOSE > 2:
print "outgoing ->", "%x" % id(self), `self._out_buffer[:sent]`
self._out_buffer = self._out_buffer[sent:]
def close(self):
if self.readfunc and self._in_buffer:
self.readfunc(self._in_buffer)
self._in_buffer = ""
#elif VERBOSE > 1 and self._in_buffer:
# print "--- there is unread data:", `self._in_buffer`
asyncore.dispatcher.close(self)
def handle_close(self):
self.close()
def handle_connect(self):
pass
class ConnectionUI:
"""Glue to let a connection tell things to the UI in a standardized way.
The protocoll defines four functions, which the connection will call:
def settotal(int total): gets called when the connection knows the data size
def setcurrent(int current): gets called when some new data has arrived
def done(): gets called when the transaction is complete
def error(type, value, tb): gets called wheneven an error occured
"""
def __init__(self, settotal_func, setcurrent_func, done_func, error_func):
self.settotal = settotal_func
self.setcurrent = setcurrent_func
self.done = done_func
self.error = error_func
class HTTPError(socket.error): pass
class HTTPClient(Connection, httplib.HTTP):
"""Asynchronous HTTP connection"""
def __init__(self, (host, port), datahandler, ui=None):
Connection.__init__(self, (host, port))
self.datahandler = datahandler
self.ui = ui
self.buf = ""
self.doneheaders = 0
self.done = 0
self.headers = None
self.length = None
self.pos = 0
def getreply(self):
raise TypeError, "getreply() is not supported in async HTTP connection"
def handle_incoming_data(self, data):
assert not self.done
if not self.doneheaders:
self.buf = self.buf + data
pos = string.find(self.buf, "\r\n\r\n")
if pos >= 0:
self.handle_reply(self.buf[:pos+4])
length = self.headers.getheader("Content-Length")
if length is not None:
self.length = int(length)
if self.ui is not None:
self.ui.settotal(self.length)
else:
self.length = -1
self.doneheaders = 1
self.handle_data(self.buf[pos+4:])
self.buf = ""
else:
self.handle_data(data)
def handle_reply(self, data):
f = cStringIO.StringIO(data)
ver, code, msg = string.split(f.readline(), None, 2)
code = int(code)
msg = string.strip(msg)
if code <> 200:
# Hm, this is what *I* need, but probably not correct...
raise HTTPError, (code, msg)
self.headers = mimetools.Message(f)
def handle_data(self, data):
self.pos = self.pos + len(data)
if self.ui is not None:
self.ui.setcurrent(self.pos)
self.datahandler(data)
if self.pos >= self.length:
self.datahandler("")
self.done = 1
if self.ui is not None:
self.ui.done()
def handle_error(self, type, value, tb):
if self.ui is not None:
self.ui.error(type, value, tb)
else:
Connection.handle_error(self, type, value, tb)
def log(self, message):
if VERBOSE:
print 'LOG:', message
class PyMessage:
def __init__(self):
self._buf = ""
self._len = None
self._checksum = None
def feed(self, data):
self._buf = self._buf + data
if self._len is None:
if len(self._buf) >= 8:
import struct
self._len, self._checksum = struct.unpack("ll", self._buf[:8])
self._buf = self._buf[8:]
if self._len is not None:
if len(self._buf) >= self._len:
import zlib
data = self._buf[:self._len]
leftover = self._buf[self._len:]
self._buf = None
assert self._checksum == zlib.adler32(data), "corrupt data"
self.data = data
return 1, leftover
else:
return 0, None
else:
return 0, None
class PyConnection(Connection):
def __init__(self, sock_or_address):
Connection.__init__(self, sock_or_address)
self.currentmessage = PyMessage()
def handle_incoming_data(self, data):
while data:
done, data = self.currentmessage.feed(data)
if done:
import cPickle
self.handle_object(cPickle.loads(self.currentmessage.data))
self.currentmessage = PyMessage()
def handle_object(self, object):
print 'unhandled object:', `object`
def send(self, object):
import cPickle, zlib, struct
data = cPickle.dumps(object, 1)
length = len(data)
checksum = zlib.adler32(data)
data = struct.pack("ll", length, checksum) + data
Connection.send(self, data)
class Echo(Connection):
"""Simple echoing connection: it sends everything back it receives."""
def handle_incoming_data(self, data):
self.send(data)
class Proxy(Connection):
"""Generic proxy connection"""
def __init__(self, sock_or_address=None, proxyaddr=None, closepartner=0):
"""arguments:
- sock_or_address is either a socket or a tuple containing the
name and port number of a remote host
- proxyaddr: a tuple containing a name and a port number of a
remote host (optional).
- closepartner: boolean, specifies whether we should close
the proxy connection (optional)"""
Connection.__init__(self, sock_or_address)
self.other = None
self.proxyaddr = proxyaddr
self.closepartner = closepartner
def close(self):
if self.other:
other = self.other
self.other = None
other.other = None
if self.closepartner:
other.close()
Connection.close(self)
def handle_incoming_data(self, data):
if not self.other:
# pass data for possible automatic remote host detection
# (see HTTPProxy)
data = self.connectproxy(data)
self.other.send(data)
def connectproxy(self, data):
other = self.__class__(self.proxyaddr, closepartner=self.closepartner)
self.other = other
other.other = self
return data
class HTTPProxy(Proxy):
"""Simple, useless, http proxy. It figures out itself where to connect to."""
def connectproxy(self, data):
if VERBOSE:
print "--- proxy request", `data`
addr, data = de_proxify(data)
other = Proxy(addr)
self.other = other
other.other = self
return data
# helper for HTTPProxy
def de_proxify(data):
import re
req_pattern = "GET http://([a-zA-Z0-9-_.]+)(:([0-9]+))?"
m = re.match(req_pattern, data)
host, dummy, port = m.groups()
if not port:
port = 80
else:
port = int(port)
# change "GET http://xx.xx.xx/yy" into "GET /yy"
data = re.sub(req_pattern, "GET ", data)
return (host, port), data
# if we're running "under W", let's register the socket poller to the event loop
try:
import W
except:
pass
else:
W.getapplication().addidlefunc(asyncore.poll)
## testing muck
#testserver = Server(10000, Connection)
#echoserver = Server(10007, Echo)
#httpproxyserver = Server(8088, HTTPProxy, 5)
#asyncore.close_all()
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