PyInvoke异步进程：读取当前输出及手动终止问题咨询

背景说明 #

官方文档提到了asynchronous=True的用法，但缺少完整的示例代码片段。我常需要查阅GitHub Issue找示例，可能是我漏看了文档内容，已提交相关Issue。

测试代码 #

@task
def my_cmd(ctx: Context):
    invoke_promise = ctx.run(
        "while true; do echo running forevah; sleep 2; done", warn=True, hide=False, echo=True, asynchronous=True
    )

遇到的问题 #

1. 执行print(invoke_promise)触发报错：

print(invoke_promise)

Traceback (most recent call last):
  File "/usr/local/bin/myproject", line 8, in <module>
    sys.exit(program.run())
  File "/usr/local/lib/python3.10/site-packages/invoke/program.py", line 384, in run
    self.execute()
  File "/usr/local/lib/python3.10/site-packages/invoke/program.py", line 569, in execute
    executor.execute(*self.tasks)
  File "/usr/local/lib/python3.10/site-packages/invoke/executor.py", line 129, in execute
    result = call.task(*args, **call.kwargs)
  File "/usr/local/lib/python3.10/site-packages/invoke/tasks.py", line 127, in __call__
    result = self.body(*args, **kwargs)
  File "/workspaces/myproject/myproject/tasks/mytask.py", line 479, in my_cmd
    print(invoke_promise)
  File "/usr/local/lib/python3.10/site-packages/invoke/runners.py", line 1475, in __str__
    if self.exited is not None:
AttributeError: 'Promise' object has no attribute 'exited'

2. 执行print(invoke_promise.stdout)同样报错：

print(invoke_promise.stdout)
AttributeError: 'Promise' object has no attribute 'stdout'

3. 执行print(invoke_promise.join())会一直挂起直到进程结束。

需求 #

• 无需等待进程结束，查看当前已产生的输出
• 读取运行中进程的输出，并可手动终止该进程

内容的提问来源于stack exchange，提问作者red888