view tests/tinyproxy.py @ 37533:df4985497986

wireproto: implement capabilities for wire protocol v2

The capabilities mechanism for wire protocol version 2 represents a
clean break from version 1.

Instead of effectively exchanging a set of capabilities, we're
exchanging a rich data structure.

This data structure currently contains information about
every available command, including its accepted arguments. It also
contains information about supported compression formats.

Exposing information about supported commands will allow clients
to automatically generate bindings to the server. Clients will be
able to do things like detect when they are attempting to run a
command that isn't known to the server. Exposing the required
permissions to run a command can be used by clients to determine if
they have privileges to call a command before actually calling it.
We could potentially even have clients send credentials
preemptively without waiting for the server to deny the command
request. Lots of potential here.

The data returned by this command will likely evolve heavily. So we
shouldn't bikeshed the implementation just yet.

Differential Revision: https://phab.mercurial-scm.org/D3200

#!/usr/bin/env python

from __future__ import absolute_import, print_function

__doc__ = """Tiny HTTP Proxy.

This module implements GET, HEAD, POST, PUT and DELETE methods
on BaseHTTPServer, and behaves as an HTTP proxy.  The CONNECT
method is also implemented experimentally, but has not been
tested yet.

Any help will be greatly appreciated.           SUZUKI Hisao
"""

__version__ = "0.2.1"

import optparse
import os
import select
import socket
import sys

from mercurial import util

httpserver = util.httpserver
socketserver = util.socketserver
urlreq = util.urlreq

if os.environ.get('HGIPV6', '0') == '1':
    family = socket.AF_INET6
else:
    family = socket.AF_INET

class ProxyHandler (httpserver.basehttprequesthandler):
    __base = httpserver.basehttprequesthandler
    __base_handle = __base.handle

    server_version = "TinyHTTPProxy/" + __version__
    rbufsize = 0                        # self.rfile Be unbuffered

    def handle(self):
        (ip, port) = self.client_address
        allowed = getattr(self, 'allowed_clients', None)
        if allowed is not None and ip not in allowed:
            self.raw_requestline = self.rfile.readline()
            if self.parse_request():
                self.send_error(403)
        else:
            self.__base_handle()

    def log_request(self, code='-', size='-'):
        xheaders = [h for h in self.headers.items() if h[0].startswith('x-')]
        self.log_message('"%s" %s %s%s',
                         self.requestline, str(code), str(size),
                         ''.join([' %s:%s' % h for h in sorted(xheaders)]))
        # Flush for Windows, so output isn't lost on TerminateProcess()
        sys.stdout.flush()
        sys.stderr.flush()

    def _connect_to(self, netloc, soc):
        i = netloc.find(':')
        if i >= 0:
            host_port = netloc[:i], int(netloc[i + 1:])
        else:
            host_port = netloc, 80
        print("\t" "connect to %s:%d" % host_port)
        try: soc.connect(host_port)
        except socket.error as arg:
            try: msg = arg[1]
            except (IndexError, TypeError): msg = arg
            self.send_error(404, msg)
            return 0
        return 1

    def do_CONNECT(self):
        soc = socket.socket(family, socket.SOCK_STREAM)
        try:
            if self._connect_to(self.path, soc):
                self.log_request(200)
                self.wfile.write(self.protocol_version +
                                 " 200 Connection established\r\n")
                self.wfile.write("Proxy-agent: %s\r\n" % self.version_string())
                self.wfile.write("\r\n")
                self._read_write(soc, 300)
        finally:
            print("\t" "bye")
            soc.close()
            self.connection.close()

    def do_GET(self):
        (scm, netloc, path, params, query, fragment) = urlreq.urlparse(
            self.path, 'http')
        if scm != 'http' or fragment or not netloc:
            self.send_error(400, "bad url %s" % self.path)
            return
        soc = socket.socket(family, socket.SOCK_STREAM)
        try:
            if self._connect_to(netloc, soc):
                self.log_request()
                soc.send("%s %s %s\r\n" % (
                    self.command,
                    urlreq.urlunparse(('', '', path, params, query, '')),
                    self.request_version))
                self.headers['Connection'] = 'close'
                del self.headers['Proxy-Connection']
                for key_val in self.headers.items():
                    soc.send("%s: %s\r\n" % key_val)
                soc.send("\r\n")
                self._read_write(soc)
        finally:
            print("\t" "bye")
            soc.close()
            self.connection.close()

    def _read_write(self, soc, max_idling=20):
        iw = [self.connection, soc]
        ow = []
        count = 0
        while True:
            count += 1
            (ins, _, exs) = select.select(iw, ow, iw, 3)
            if exs:
                break
            if ins:
                for i in ins:
                    if i is soc:
                        out = self.connection
                    else:
                        out = soc
                    try:
                        data = i.recv(8192)
                    except socket.error:
                        break
                    if data:
                        out.send(data)
                        count = 0
            else:
                print("\t" "idle", count)
            if count == max_idling:
                break

    do_HEAD = do_GET
    do_POST = do_GET
    do_PUT  = do_GET
    do_DELETE = do_GET

class ThreadingHTTPServer (socketserver.ThreadingMixIn,
                           httpserver.httpserver):
    def __init__(self, *args, **kwargs):
        httpserver.httpserver.__init__(self, *args, **kwargs)
        a = open("proxy.pid", "w")
        a.write(str(os.getpid()) + "\n")
        a.close()

def runserver(port=8000, bind=""):
    server_address = (bind, port)
    ProxyHandler.protocol_version = "HTTP/1.0"
    httpd = ThreadingHTTPServer(server_address, ProxyHandler)
    sa = httpd.socket.getsockname()
    print("Serving HTTP on", sa[0], "port", sa[1], "...")
    try:
        httpd.serve_forever()
    except KeyboardInterrupt:
        print("\nKeyboard interrupt received, exiting.")
        httpd.server_close()
        sys.exit(0)

if __name__ == '__main__':
    argv = sys.argv
    if argv[1:] and argv[1] in ('-h', '--help'):
        print(argv[0], "[port [allowed_client_name ...]]")
    else:
        if argv[2:]:
            allowed = []
            for name in argv[2:]:
                client = socket.gethostbyname(name)
                allowed.append(client)
                print("Accept: %s (%s)" % (client, name))
            ProxyHandler.allowed_clients = allowed
            del argv[2:]
        else:
            print("Any clients will be served...")

        parser = optparse.OptionParser()
        parser.add_option('-b', '--bind', metavar='ADDRESS',
                          help='Specify alternate bind address '
                               '[default: all interfaces]', default='')
        (options, args) = parser.parse_args()
        port = 8000
        if len(args) == 1:
            port = int(args[0])
        runserver(port, options.bind)