python - 如何从装饰器向基于 Django 类的 View 添加/修改属性？

Question

我有一个基于类的 Django View ，如下所示:

class myView(TemplateView):
    template_name = 'templateFile.html'
    request = None

    @method_decorator(request_management)
    def dispatch(self, request, *args, **kwargs):
        ...
        return super(myView, self).dispatch(request, *args, **kwargs)

    def get_context_data(self, *args, **kwargs):
        ctx = super(newFeatures, self).get_context_data(**kwargs)
        ctx['requester'] = self.requester
        return ctx

在我的 request_management 装饰器中，我想将 myView.request 的值设置为传递到调度函数中的参数。所以我做了这样的事情:

def request_management(function):
    @wraps(function)
    def decorator(*args, **kwargs):
        logger.debug("request = %s" % str(args[0]))
        # I want to say here something like: 
        # self.request = args[0]
        # but of course, "self" is not defined in this context.
        return function(*args, **kwargs)
    return decorator

但是从装饰器内部，我无法访问装饰方法的“self”实例。如何获取该实例并向其附加一个名为 request 的属性，以便我可以在该实例的其他方法中使用该属性？

Answer 1

method_decorator 的目的是 convert a function decorator into a method decorator 。但由于您正在编写自己的装饰器，因此您可以继续将其编写为实际的方法装饰器:

class myView(TemplateView):

    @request_management
    def dispatch(self, request, *args, **kwargs):
        ... 
        return super(myView, self).dispatch(request, *args, **kwargs)

    def request_management(method): 
        @wraps(method)
        def decorator(self, request, *args, **kwargs):
            logger.debug("request = %s" % str(request))
            self.request = request

            return method(self, request, *args, **kwargs)

        return decorator