这个课程是这个博客的博主发起的一个众筹项目，博主blog写得不错，也很喜欢教学，因此就有了这个项目，项目资金达到1w+美元之后，所有的视频都会免费发布。
第三课继续将讲解第二课的脚本，该脚本的功能是实现一个网络中转服务
能使用更高级的库就不要使用低级的库
用threading而不是thread字符串分割可以用partition
比起用
贴上最后修改好的源码，全部源码在这里：
"""An HTTP proxy that supports IPv6 as well as the HTTP CONNECT method, among
other things."""
# Standard libary imports
import socket
import threading
import select
__version__ = '0.1.0 Draft 1'
BUFFER_LENGTH = 8192
VERSION = 'Python Proxy/{}'.format(__version__)
HTTP_VERSION = 'HTTP/1.1'
class Proxy(object):
"""Handles connections between the HTTP client and HTTP server."""
def __init__(self, connection):
self.client = connection
self.client_buffer = ''
self.target = None
method, path, protocol = self.get_base_header()
if method == 'CONNECT':
self.method_connect(path)
else:
self.method_others(method, path, protocol)
def get_base_header(self):
"""Return a tuple of (method, path, protocol) from the recieved
message."""
while '\n' not in self.client_buffer:
self.client_buffer += self.client.recv(BUFFER_LENGTH)
(data, _, self.client_buffer) = self.client_buffer.partition('\n')
return data.split()
def method_connect(self, path):
"""Handle HTTP CONNECT messages."""
self._connect_to_target(path)
self.client.send('{http_version} 200 Connection established\n'
'Proxy-agent: {version}\n\n'.format(
http_version=HTTP_VERSION,
version=VERSION))
self.client_buffer = ''
self._read_write()
def method_others(self, method, path, protocol):
"""Handle all non-HTTP CONNECT messages."""
path = path[len('http://'):]
host, _, path = path.partition('/')
path = '/{}'.format(path)
self._connect_to_target(host)
self.target.send('{method} {path} {protocol}\n{client_buffer}'.format(
method=method,
path=path,
protocol=protocol,
client_buffer=self.client_buffer))
self.client_buffer = ''
self._read_write()
def _connect_to_target(self, host):
"""Create a connection to the HTTP server specified by *host*."""
port = 80
if ':' in host:
host, _, port = host.partition(':')
(socket_family, _, _, _, address) = socket.getaddrinfo(host, port)[0]
self.target = socket.socket(socket_family)
self.target.connect(address)
def _read_write(self):
"""Read data from client connection and forward to server
connection."""
sockets = [self.client, self.target]
try:
while 1:
(receive, _, error) = select.select(sockets, [], sockets, 10)
if error:
break
elif receive:
for source in receive:
data = source.recv(BUFFER_LENGTH)
if not data:
return
if source is self.client:
destination = self.target
else:
destination = self.client
destination.sendall(data)
finally:
self.client.close()
self.target.close()
def start_server():
"""Start the HTTP proxy server."""
host = 'localhost'
port = 8080
listener = socket.socket(socket.AF_INET)
listener.bind((host, port))
print 'Serving on {0}:{1}.'.format(host, port)
listener.listen(0)
while 1:
connection, address = listener.accept()
print 'Got connection from {}'.format(address)
threading.Thread(
target=Proxy, args=(connection, )).run()
if __name__ == '__main__':
start_server()
