瓶子服务器：删除路线

编程问答 2022-08-14

问题描述

我想在我的瓶子服务器运行时添加和删除路由。

我的一般问题：是否有删除路由的正确方法？

换句话说：我该如何撤消对app.route所做的操作？

在下文中，我将更详细地描述我的问题。如果您知道我的一般问题的答案，请不要浪费时间阅读它。

这是一个演示脚本，描述了我如何解决问题：

如果致电 GET / add ：添加了“ Hello World”路线

如果调用 GET / remove （获取/删除）：所有具有相同前缀（例如'Hello World'路线）的路线都会触发 404错误 

import bottle
from bottle import redirect,abort

def addRoute():
    app.route('/route/hello')(lambda :'Hello World')
    print('Routes after calling /add:\n' + '\n'.join([str(route) for route in app.routes]))
    redirect('route/hello')

def removeRoute():
    prefix = '/route/hello'

    #making a list of all routes having the prefix
    #because this is a testfile there is only one rule that startswith prefix
    routes = [route for route in app.routes if route.rule.startswith(prefix)]

    #because there Could be multiple routes with the same rule and method,#making a list without duplicates
    ruleMethodTuples = list(dict.fromkeys([(route.rule,route.method) for route in routes]))

    for ruleMethod in ruleMethodTuples :

        #Workaround: Overwriting the existing route with a 404
        #Here I'd prefer to make a statement that removes the existing route instead,#so the default 404 would be called
        app.route(ruleMethod[0],method = ruleMethod[1])(lambda **kwords: abort(404,'Route deleted'))

    print('Routes after calling /remove:\n' + '\n'.join([str(route) for route in app.routes]))
    redirect('/route/hello')

if __name__ == '__main__':
    app = bottle.app()
    app.route('/add')(addRoute)
    app.route('/remove')(removeRoute)
    print('Initial routes:\n' + '\n'.join([str(route) for route in app.routes]))
    bottle.run(app,host = 'localhost',port = 8080)

因此，这是启动并调用后的输出：

/添加

/删除

/添加

显示每次呼叫后 app.routes 中的路由。

Initial routes:
<GET '/add' <function addRoute at 0x02A876A8>>
<GET '/remove' <function removeRoute at 0x00F5F420>>
Bottle v0.12.17 server starting up (using WsgiRefServer())...
Listening on http://localhost:8080/
Hit Ctrl-C to quit.

Routes after calling /add:
<GET '/add' <function addRoute at 0x02A876A8>>
<GET '/remove' <function removeRoute at 0x00F5F420>>
<GET '/route/hello' <function addRoute.<locals>.<lambda> at 0x030C3E88>>
127.0.0.1 - - [25/Aug/2020 23:19:09] "GET /add HTTP/1.1" 303 0
127.0.0.1 - - [25/Aug/2020 23:19:09] "GET /route/hello HTTP/1.1" 200 11
Routes after calling /remove:
<GET '/add' <function addRoute at 0x02A876A8>>
<GET '/remove' <function removeRoute at 0x00F5F420>>
<GET '/route/hello' <function addRoute.<locals>.<lambda> at 0x030C3E88>>
<GET '/route/hello' <function removeRoute.<locals>.<lambda> at 0x030C3FA8>>
127.0.0.1 - - [25/Aug/2020 23:19:14] "GET /remove HTTP/1.1" 303 0
127.0.0.1 - - [25/Aug/2020 23:19:14] "GET /route/hello HTTP/1.1" 404 720
Routes after calling /add:
<GET '/add' <function addRoute at 0x02A876A8>>
<GET '/remove' <function removeRoute at 0x00F5F420>>
<GET '/route/hello' <function addRoute.<locals>.<lambda> at 0x030C3E88>>
<GET '/route/hello' <function removeRoute.<locals>.<lambda> at 0x030C3FA8>>
<GET '/route/hello' <function addRoute.<locals>.<lambda> at 0x030E0270>>
127.0.0.1 - - [25/Aug/2020 23:19:17] "GET /add HTTP/1.1" 303 0
127.0.0.1 - - [25/Aug/2020 23:19:18] "GET /route/hello HTTP/1.1" 200 11

因此，代替了 GET'/ route / hello'，呼叫： app.route 使用相同的方法添加了更多路由，并且规则在列表的末尾。

到目前为止，这仍然有效，因为首先选择了最新的匹配路由，但是我敢肯定，这会（早晚）导致性能问题或在调用某些 / add后导致服务器崩溃 strong>和 /删除。

我还注意到，我可以更改 app.routes 而无需更改实际路由，因此第二个问题：

我是否可以从app.routes中删除“已弃用”的路由以防止堆栈溢出？

第三个问题：

我是否正在以完全错误的方式进行操作？

解决方法

我检查了add_route的源代码

它将route添加到两个对象：self.routes和self.router（app.routes和app.router），这会带来问题。

def add_route(self,route):
    """ Add a route object,but do not change the :data:`Route.app`
        attribute."""
    self.routes.append(route)
    self.router.add(route.rule,route.method,route,name=route.name)
    if DEBUG: route.prepare()

self.router是对象Router，具有rules，builder，static dyna_routes，dyna_regexes

如果在添加新路线之前和之后进行检查，则会看到builder和static中的变化。

def addRoute():
    print('--- before ---')
    print(app.router.rules)
    print(app.router.builder)
    print(app.router.static)
    print(app.router.dyna_routes)
    
    app.route('/route/hello')(lambda :'Hello World')

    print('--- after ---')
    print(app.router.rules)
    print(app.router.builder)
    print(app.router.static)
    print(app.router.dyna_routes)

    print('Routes after calling /add:\n' + '\n'.join([str(route) for route in app.routes]))
    redirect('route/hello')

如果我从'/route/hello'和builder中删除了static，则'/route/hello'停止工作，但是app.routes仍然显示了它们，因此您必须删除{{1} } '/route/hello'和app.routes中的}-但它们没有特殊的功能：）

app.router

我的完整代码：

def removeRoute():
    prefix = '/route/hello'

    del app.router.builder[prefix]
    del app.router.static['GET'][prefix]
    
    print('Routes after calling /remove:\n' + '\n'.join([str(route) for route in app.routes]))
    redirect('/route/hello')
bottlepythonurl-routing