Django 如何保证中间件的 init 只被调用一次？

Question

Django 的文档：

Unlike the process_* methods which get called once per request, __init__ gets called only once, when the Web server responds to the first request.

Django如何保证中间件对象只初始化一次？ Web 服务器可以启动多个 python 解释器实例来处理请求，对吗？

Answer 1

这意味着每个解释器实例一次。注意实现：

class WSGIHandler(base.BaseHandler):
  # ...
  def __call__(self, environ, start_response):
    # ...
    if self._request_middleware is None:
        self.load_middleware()

您可以阅读 django/core/handlers/wsgi.py and django/core/handlers/base.py（尤其是 Basehandler.load_middleware）了解更多详情。

Django 如何保证中间件的 init 只被调用一次？

How does Django guarantee a middleware's init to be called only once?

python

django

middleware

django-middleware

Django 如何保证中间件的 __init__ 只被调用一次？

How does Django guarantee a middleware's __init__ to be called only once?

python

django

middleware

django-middleware

Django 如何保证中间件的 init 只被调用一次？

How does Django guarantee a middleware's init to be called only once?