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input - 无法从异步中的标准输入读取文件

问题描述

我编写了一个适用于 asyncio 的代码。在该代码中，我必须使用./check.py < file.txt 我能够从终端提供输入来从标准输入中读取文件。通常它工作正常。但它不适用于从标准输入中读取文件中的数据。

#!/usr/bin/env python3.6

import asyncio
from aioconsole import ainput

async def read_input():
    while True:
        inp = await ainput()
        print('got ' + inp)

if (__name__ == "__main__"):
    asyncio.get_event_loop().run_until_complete(read_input())

通常它的工作原理是

$ ./check.py 
4
got 4
5
got 5

但是在直接从文件中读取时，我面对这个日志：

$ ./check.py < test/test_case 
Traceback (most recent call last):
  File "./check.py", line 12, in <module>
    asyncio.get_event_loop().run_until_complete(read_input())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 468, in run_until_complete
    return future.result()
  File "./check.py", line 8, in read_input
    inp = await ainput()
  File "/usr/local/lib/python3.6/dist-packages/aioconsole/stream.py", line 156, in ainput
    reader, writer = yield from get_standard_streams(loop=loop)
  File "/usr/local/lib/python3.6/dist-packages/aioconsole/stream.py", line 144, in get_standard_streams
    cache[key] = yield from connection
  File "/usr/local/lib/python3.6/dist-packages/aioconsole/stream.py", line 132, in create_standard_streams
    reader, writer = yield from future
  File "/usr/local/lib/python3.6/dist-packages/aioconsole/stream.py", line 114, in open_pipe_connection
    yield from loop.connect_read_pipe(lambda: protocol, pipe_in)
  File "/usr/lib/python3.6/asyncio/base_events.py", line 1099, in connect_read_pipe
    transport = self._make_read_pipe_transport(pipe, protocol, waiter)
  File "/usr/lib/python3.6/asyncio/unix_events.py", line 185, in _make_read_pipe_transport
    return _UnixReadPipeTransport(self, pipe, protocol, waiter, extra)
  File "/usr/lib/python3.6/asyncio/unix_events.py", line 353, in __init__
    raise ValueError("Pipe transport is for pipes/sockets only.")
ValueError: Pipe transport is for pipes/sockets only.

无法理解为什么它的行为不同？我想像./check.py < file.txt使用协程一样读取文件。

标签： inputpython-3.6python-asyncio

解决方案

这是aioconsole v0.1.9中修复的错误。

只需运行以下命令即可获取最新版本：

$ pip3 install -U aioconsole

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