#!/usr/bin/python
#
#?Server?that?will?accept?connections?from?a?Vim?channel.
#?Run?this?server?and?then?in?Vim?you?can?open?the?channel:
#??:let?handle?=?ch_open（‘localhost:8765‘）
#
#?Then?Vim?can?send?requests?to?the?server:
#??:let?response?=?ch_sendexpr（handle?‘hello!‘）
#
#?And?you?can?control?Vim?by?typing?a?JSON?message?here?e.g.:
#???[“ex““echo?‘hi?there‘“]
#
#?There?is?no?prompt?just?type?a?line?and?press?Enter.
#?To?exit?cleanly?type?“quit“.
#
#?See?“:help?channel-demo“?in?Vim.
#
#?This?requires?Python?2.6?or?later.

from?__future__?import?print_function
import?json
import?socket
import?sys
import?threading

try:
????#?Python?3
????import?socketserver
except?ImportError:
????#?Python?2
????import?SocketServer?as?socketserver

thesocket?=?None

class?ThreadedTCPRequestHandler（socketserver.baseRequestHandler）:

????def?handle（self）:
????????print（“===?socket?opened?===“）
????????global?thesocket
????????thesocket?=?self.request
????????while?True:
????????????try:
????????????????data?=?self.request.recv（4096）.decode（‘utf-8‘）
????????????except?socket.error:
????????????????print（“===?socket?error?===“）
????????????????break
????????????except?IOError:
????????????????print（“===?socket?closed?===“）
????????????????break
????????????if?data?==?‘‘:
????????????????print（“===?socket?closed?===“）
????????????????break
????????????print（“received:?{0}“.format（data））
????????????try:
????????????????decoded?=?json.loads（data）
????????????except?ValueError:
????????????????print（“json?decoding?failed“）
????????????????decoded?=?[-1?‘‘]

????????????#?Send?a?response?if?the?sequence?number?is?positive.
????????????#?Negative?numbers?are?used?for?“eval“?responses.
????????????if?decoded[0]?>=?0:
????????????????if?decoded[1]?==?‘hello!‘:
????????????????????response?=?“got?it“
????????????????else:
????????????????????response?=?“what?“
????????????????encoded?=?json.dumps（[decoded[0]?response]）
????????????????print（“sending?{0}“.format（encoded））
????????????????self.request.sendall（encoded.encode（‘utf-8‘））
????????thesocket?=?None

class?ThreadedTCPServer（socketserver.ThreadingMixIn?socketserver.TCPServer）:
????pass

if?__name__?==?“__main__“:
????HOST?PORT?=?“localhost“?8765

????server?=?ThreadedTCPServer（（HOST?PORT）?ThreadedTCPRequestHandler）
????ip?port?=?server.server_address

????#?Start?a?thread?with?the?server?--?that?thread?will?then?start?one
????#?more?thread?for?each?request
????server_thread?=?threading.Thread（target=server.serve_forever）

????#?Exit?the?server?thread?when?the?main?thread?terminates
????server_thread.daemon?=?True
????server_thread.start（）
????print（“Server?loop?running?in?thread:?“?server_thread.name）

????print（“Listening?on?port?{0}“.format（PORT））
????while?True:
????????typed?=?sys.stdin.readline（）
????????if?“quit“?in?typed:
????????????print（“Goodbye!“）
????????????break
????????if?thesocket?is?None:
????????????print（“No?socket?yet“）
????????else:
????????????print（“sending?{0}“.format（type