online compiler这是我的网站，用户可以在其中运行控制台程序。
目前，用户必须在运行程序之前输入程序输入。我正在尝试为程序建立实时用户输入（希望提供与他们在笔记本电脑上运行程序相同的体验）。
在研究中，我遇到了一个使用websocket流stdout和stdin的解决方案。
我的实施
# coding: utf-8
import subprocess
import thread
from tornado.websocket import WebSocketHandler
from nbstreamreader import NonBlockingStreamReader as NBSR
class WSHandler(WebSocketHandler):
def open(self):
self.write_message("connected")
self.app = subprocess.Popen(['sh', 'app/shell.sh'], stdout=subprocess.PIPE, stdin=subprocess.PIPE,
shell=False)
self.nbsr = NBSR(self.app.stdout)
thread.start_new_thread(self.soutput, ())
def on_message(self, incoming):
self.app.stdin.write(incoming)
def on_close(self):
self.write_message("disconnected")
def soutput(self):
while True:
output = self.nbsr.readline(0.1)
# 0.1 secs to let the shell output the result
if not output:
print 'No more data'
break
self.write_message(output)
nbstreamreader.py
from threading import Thread
from Queue import Queue, Empty
class NonBlockingStreamReader:
def __init__(self, stream):
'''
stream: the stream to read from.
Usually a process' stdout or stderr.
'''
self._s = stream
self._q = Queue()
def _populateQueue(stream, queue):
'''
Collect lines from 'stream' and put them in 'quque'.
'''
while True:
line = stream.readline()
if line:
queue.put(line)
else:
raise UnexpectedEndOfStream
self._t = Thread(target=_populateQueue,
args=(self._s, self._q))
self._t.daemon = True
self._t.start() # start collecting lines from the stream
def readline(self, timeout=None):
try:
return self._q.get(block=timeout is not None,
timeout=timeout)
except Empty:
return None
class UnexpectedEndOfStream(Exception): pass
shell.sh
#!/usr/bin/env bash
echo "hello world"
echo "hello world"
read -p "Your first name: " fname
read -p "Your last name: " lname
echo "Hello $fname $lname ! I am learning how to create shell scripts"
此代码流stdout直到shell.sh代码到达read语句。
请指导我我在做什么错。为什么它不等待标准输入并在完成程序执行之前到达打印“ No more data”的信息？
测试它的源代码https://github.com/mryogesh/streamconsole.git
最佳答案
除非您在100毫秒内发送输入，否则您的readline()方法将超时，这将中断循环。您没有看到read -p提示符的原因是缓冲（由于readline和管道缓冲）。最后，您的示例javascript不会发送尾随换行符，因此read不会返回。
如果增加超时时间，请添加换行符和find a way to work around buffering issues，示例基本上应该可以正常工作。
我还将使用tornado.process和协程而不是子进程和线程：
from tornado import gen
from tornado.process import Subprocess
from tornado.ioloop import IOLoop
from tornado.iostream import StreamClosedError
from tornado.websocket import WebSocketHandler
class WSHandler(WebSocketHandler):
def open(self):
self.app = Subprocess(['script', '-q', 'sh', 'app/shell.sh'], stdout=Subprocess.STREAM, stdin=Subprocess.STREAM)
IOLoop.current().spawn_callback(self.stream_output)
def on_message(self, incoming):
self.app.stdin.write(incoming.encode('utf-8'))
@gen.coroutine
def stream_output(self):
try:
while True:
line = yield self.app.stdout.read_bytes(1000, partial=True)
self.write_message(line.decode('utf-8'))
except StreamClosedError:
pass
关于python - 带有websocket的实时流stdout和stdin，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/41431882/