_cp_dispatch (Cherrypy) 的奇怪行为答案

【问题标题】：Weird behavour of _cp_dispatch (Cherrypy)_cp_dispatch (Cherrypy) 的奇怪行为
【发布时间】：2018-07-28 18:28:08
【问题描述】：

我有一个提供文件的应用程序。 HTTP GET/POST/PUT/DELETE 方法应该做不同的事情（显然）。因此，我编写了一个对象来表示提供 GET/POST/... 方法的文件。该文件由调度程序应用程序的_cp_dispatch 方法返回。查看我的源代码。

但是 Cherrypy 引发了一个异常，指出

TypeError: 'DispatchedFile1' object is not callable
TypeError: unsupported callable
TypeError: <__main__.DispatchedFile1 object at 0x7f209b4e7d30> is not a callable object

如果我使用 @expose d index 方法创建 Web 应用程序的“正常”方式，则此示例可以正常工作。

import cherrypy, os

@cherrypy.expose
class DispatchedFile1(object):
    def __init__(self, path):
        self._path = path

    def GET(self, start = 0, chunk_size = 0):
        if(start and chunk_size):
            return "{} ; OFFSET: {}, CHUNK_SIZE: {}".format(self._path,
                    start, chunk_size).encode("UTF-8")
        return self._path.encode("UTF-8")
class DispatchedFile2(object):
    def __init__(self, path):
        self._path = path

    @cherrypy.expose
    def index(self, start = 0, chunk_size = 0):
        if(start and chunk_size):
            return "{} ; OFFSET: {}, CHUNK_SIZE: {}".format(self._path,
                    start, chunk_size).encode("UTF-8")
        return self._path.encode("UTF-8")


class FileDispatcherApp1(object):
    def _cp_dispatch(self, vpath):
        print(vpath)

        res = DispatchedFile1("/".join(vpath))
        vpath.clear()
        print(vpath)
        return res

class FileDispatcherApp2(object):
    def _cp_dispatch(self, vpath):
        print(vpath)

        res = DispatchedFile2("/".join(vpath))
        vpath.clear()
        print(vpath)
        return res


class DummyApp(object):
    @cherrypy.expose
    def index(self):
        return "index"

cherrypy.tree.mount(FileDispatcherApp1(), "/files1")
cherrypy.tree.mount(FileDispatcherApp2(), "/files2")
cherrypy.quickstart(DummyApp(), "/")

第二个版本运行良好，但不能满足我的需求。我在这里错过了什么吗？如何修复我的第一个版本？

PS.：我知道我可以使用cherrypy.request手动查找方法。

【问题讨论】：

标签： python-3.x cherrypy

【解决方案1】：

好吧，原来我忘了添加正确的请求调度程序。

正确的源代码是：

import cherrypy, os

@cherrypy.expose
class DispatchedFile1(object):
    def __init__(self, path):
        self._path = path

    def GET(self, start = 0, chunk_size = 0):
        if(start and chunk_size):
            return "{} ; OFFSET: {}, CHUNK_SIZE: {}".format(self._path,
                    start, chunk_size).encode("UTF-8")
        return self._path.encode("UTF-8")
class DispatchedFile2(object):
    def __init__(self, path):
        self._path = path

    @cherrypy.expose
    def index(self, start = 0, chunk_size = 0):
        if(start and chunk_size):
            return "{} ; OFFSET: {}, CHUNK_SIZE: {}".format(self._path,
                    start, chunk_size).encode("UTF-8")
        return self._path.encode("UTF-8")


class FileDispatcherApp1(object):
    def _cp_dispatch(self, vpath):
        print(vpath)

        res = DispatchedFile1("/".join(vpath))
        vpath.clear()
        print(vpath)
        return res

class FileDispatcherApp2(object):
    def _cp_dispatch(self, vpath):
        print(vpath)

        res = DispatchedFile2("/".join(vpath))
        vpath.clear()
        print(vpath)
        return res


class DummyApp(object):
    @cherrypy.expose
    def index(self):
        return "index"

cherrypy.tree.mount(FileDispatcherApp1(), "/files1", {"/": {'request.dispatch': cherrypy.dispatch.MethodDispatcher()}})
cherrypy.tree.mount(FileDispatcherApp2(), "/files2")
cherrypy.quickstart(DummyApp(), "/")

安装应用时注意{'request.dispatch': cherrypy.dispatch.MethodDispatcher()}。

【讨论】：