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默认的 CherryPy 路由样式基于类的实例,其方法由@cherrypy.expose.

在下面的示例中,这些 url 是通过对其他普通类进行简单调整来提供的。

/
/hello
/hello/again
/bye
/bye/again

我想知道是否有办法使用 Flask 的 @route 或其他装饰器来实现这一点。

import cherrypy

class Root(object):
    @cherrypy.expose
    def index(self):
        return 'my app'

class Greeting(object):
    def __init__(self, name, greeting):
        self.name = name
        self.greeting = greeting

    @cherrypy.expose
    def index(self):
        return '%s %s!' %(self.greeting, self.name)

    @cherrypy.expose
    def again(self):
        return '%s again, %s!' %(self.greeting, self.name)

if __name__ == '__main__':
    root = Root()
    root.hello = Greeting('Foo', 'Hello')
    root.bye = Greeting('Bar', 'Bye')
    cherrypy.quickstart(root)
4

1 回答 1

2

为了做这样的事情,你必须使用一点 python 魔法,但是,绝对可以用烧瓶来做。复制您的示例最直接的方法是子类化烧瓶。这是一种方法:

import inspect
from flask import Flask


def expose(f):
    """Decorator that flags a method to be exposed"""
    f._exposed_method = True
    return f


class FlaskOfCherryPy(Flask):
    """Custom flask that allows cherrypy's expose decorator"""
    def quickstart(self, root_handler, *args, **kwargs):
        self._process_root_handler(root_handler)
        self.run(*args, **kwargs)

    def _process_root_handler(self, root_handler):
        # Prime the recursive processing
        root_url = []
        self._process_a_handler(root_handler, root_url)

    def _process_a_handler(self, current_handler, url_stack):
        # This gives a list of all the members of current_handler
        members = inspect.getmembers(current_handler)
        for name, value in members:
            # You probably want to skip things that start with a _ or __
            if name.startswith('_'):
                continue

            # Check if the method is decorated
            is_exposed_method = getattr(value, '_exposed_method', False)

            # If it's a callable with the _exposed_method attribute set
            # Then it's an exposed method
            if is_exposed_method and callable(value):
                self._add_exposed_url(url_stack, name, value)
            else:
                new_stack = url_stack[:]
                new_stack.append(name)
                self._process_a_handler(value, new_stack)

    def _add_exposed_url(self, url_stack, name, view_func):
        copied_stack = url_stack[:]

        if name != 'index':
            copied_stack.append(name)

        url = "/%s" % "/".join(copied_stack)

        if name == 'index':
            copied_stack.append(name)

        view_name = "_".join(copied_stack)
        self.add_url_rule(url, view_name, view_func)


class Root(object):
    @expose
    def index(self):
        return 'my app'


class Greeting(object):
    def __init__(self, name, greeting):
        self.name = name
        self.greeting = greeting

    @expose
    def index(self):
        return '%s %s!' %(self.greeting, self.name)

    @expose
    def again(self):
        return '%s again, %s!' %(self.greeting, self.name)


if __name__ == '__main__':
    root = Root()
    root.hello = Greeting('Foo', 'Hello')
    root.bye = Greeting('Bar', 'Bye')
    app = FlaskOfCherryPy(__name__)
    app.quickstart(root)

本质上,诀窍是获取所有带有属性标记的方法 _exposed_method并将它们传递给Flask.add_url_rule请参阅此处的文档)。flask 的美妙之处在于它是一个轻量级的系统,扩展它并不可怕。我强烈建议您自己尝试一下,但我很高兴解决您的问题,因此我将脚本作为要点

我编写的这个特定代码并不完美,也没有经过大量测试,但它绝对适用于您的特定用例。此外,这不一定是您希望在生产中运行应用程序的方式。您必须创建某种应用程序工厂才能做到这一点。再次,我强烈建议研究烧瓶的内部结构,以使其做你想做的事。您可能还想查看flask 提供的基于类的视图或蓝图。他们能够做一些类似于你在这里的事情。当然,使用它们是非常不同的,并且我知道使用普通蓝图无法设置实例属性。同样,您可以随时扩展:-)

于 2012-08-21T06:42:24.110 回答