每次请求后，带有cheroot服务器结果的服务器Flask应用程序都会在HTTPServer.tick中出错

Question

我正在尝试使用CherryPy (v18.6.0)的cheroot服务器为Flask (v1.1.2) wsgi应用程序提供服务，每次通过邮递员或浏览器执行请求后，我的控制台中都会出现以下异常。我正在运行python v3.8.5

Error in HTTPServer.tick
Traceback (most recent call last):
    File "C:\myproject\venv\lib\site-packages\cheroot\server.py", line 1795, in serve
self.tick()
    File "C:\myproject\venv\lib\site-packages\cheroot\server.py", line 2030, in tick
self.connections.expire()
    File "C:\myproject\venv\lib\site-packages\cheroot\connections.py", line 107, in expire
for sock_fd, conn in timed_out_connections:
    File "C:\myproject\venv\lib\site-packages\cheroot\connections.py", line 103, in <genexpr>
(sock_fd, conn)
    File "C:\python\lib\_collections_abc.py", line 743, in __iter__
for key in self._mapping:
RuntimeError: dictionary changed size during iteration

代码如下：

from cheroot.wsgi import Server
from flask import Flask

app = Flask(__name__)

@app.route("/", methods=["GET"])
def index():
    return "Hello"

if __name__ == "__main__":
    server = Server(bind_addr=("0.0.0.0", 3000), wsgi_app=app)
    try:
         server.start()
    finally:
         server.stop()

你知道导致这种异常的原因以及我们如何解决它吗？

Answer 1

这是cheroot最近出现的一个公认问题，请查看cheroot GitHub Issue 312。