proxy.py/proxy/plugin/proxy_pool.py

85 lines
3.0 KiB
Python

# -*- coding: utf-8 -*-
"""
proxy.py
~~~~~~~~
⚡⚡⚡ Fast, Lightweight, Pluggable, TLS interception capable proxy server focused on
Network monitoring, controls & Application development, testing, debugging.
:copyright: (c) 2013-present by Abhinav Singh and contributors.
:license: BSD, see LICENSE for more details.
"""
import random
import socket
from typing import Optional, Any
from ..common.constants import DEFAULT_BUFFER_SIZE, SLASH, COLON
from ..common.utils import new_socket_connection
from ..http.proxy import HttpProxyBasePlugin
from ..http.parser import HttpParser
class ProxyPoolPlugin(HttpProxyBasePlugin):
"""Proxy incoming client proxy requests through a set of upstream proxies."""
# Run two separate instances of proxy.py
# on port 9000 and 9001 BUT WITHOUT ProxyPool plugin
# to avoid infinite loops.
UPSTREAM_PROXY_POOL = [
('localhost', 9000),
('localhost', 9001),
]
def __init__(self, *args: Any, **kwargs: Any) -> None:
super().__init__(*args, **kwargs)
self.conn: Optional[socket.socket] = None
def before_upstream_connection(
self, request: HttpParser) -> Optional[HttpParser]:
"""Avoid upstream connection of server in the request.
Initialize, connection to upstream proxy.
"""
# Implement your own logic here e.g. round-robin, least connection etc.
self.conn = new_socket_connection(
random.choice(self.UPSTREAM_PROXY_POOL))
return None
def handle_client_request(
self, request: HttpParser) -> Optional[HttpParser]:
request.path = self.rebuild_original_path(request)
self.tunnel(request)
# Returning None indicates core to gracefully
# flush client buffer and teardown the connection
return None
def handle_upstream_chunk(self, chunk: memoryview) -> memoryview:
"""Will never be called since we didn't establish an upstream connection."""
return chunk
def on_upstream_connection_close(self) -> None:
"""Will never be called since we didn't establish an upstream connection."""
pass
def tunnel(self, request: HttpParser) -> None:
"""Send to upstream proxy, receive from upstream proxy, queue back to client."""
assert self.conn
self.conn.send(request.build())
response = self.conn.recv(DEFAULT_BUFFER_SIZE)
self.client.queue(memoryview(response))
@staticmethod
def rebuild_original_path(request: HttpParser) -> bytes:
"""Re-builds original upstream server URL.
proxy server core by default strips upstream host:port
from incoming client proxy request.
"""
assert request.url and request.host and request.port and request.path
return (
request.url.scheme +
COLON + SLASH + SLASH +
request.host +
COLON +
str(request.port).encode() +
request.path
)