匿名类继承

Question

我正在围绕设备配置构建一个python自动化API,看起来像这样......

root@EX4200-24T# show interfaces ge-0/0/6 
mtu 9216;
unit 0 {
    family ethernet-switching {
        port-mode trunk;
        vlan {
            members [ v100 v101 v102 ];
        }
    }
}

root@EX4200-24T#

我正在为某些动作(如SET)定义python类,以及为动作的关键字定义类......想法是SET将遍历关键字类并将类对象附加到接口.

问题是这个设备的配置非常分层......例如,如果有很多ethernet-switching实例,我不希望API用户必须使用:

# Note that each keyword corresponds to a python class that is appended
# to an InterfaceList object behind the scenes...
SET(Interface='ge-0/0/6.0', Family='ethernet-switching', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])
SET(Interface='ge-0/0/7.0', Family='ethernet-switching', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])
SET(Interface='ge-0/0/8.0', Family='ethernet-switching', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])

相反,我希望能够使用:

Family('ethernet-switching')
SET(Interface='ge-0/0/6.0', PortMode='trunk', Vlan=['v100', 'v101', 'v102'])
SET(Interface='ge-0/0/7.0', PortMode='trunk', Vlan=['v100', 'v101', 'v102'])
SET(Interface='ge-0/0/8.0', PortMode='trunk', Vlan=['v100', 'v101', 'v102'])
Family(None)
# API usage continues...

但是,我无法想出一种在python中编写代码的方法而不诉诸于此类...

f = Family('ethernet-switching')
f.SET(Interface='ge-0/0/6.0', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])
f.SET(Interface='ge-0/0/7.0', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])
f.SET(Interface='ge-0/0/8.0', PortMode='trunk', 
    Vlan=['v100', 'v101', 'v102'])

在我需要SET()从多个类继承之前,这并不是那么糟糕......比如......

首选API

# Note: there could be many combinations of classes to inherit from
Family('ethernet-switching')
PortMode('trunk')
SET(Interface='ge-0/0/6.0', Vlan=['v100', 'v101', 'v102'])
SET(Interface='ge-0/0/7.0', Vlan=['v100', 'v101', 'v102'])
PortMode('access')
SET(Interface='ge-0/0/8.0', Vlan=['v100'])
SET(Interface='ge-0/0/9.0', Vlan=['v100'])
Family(None)
PortMode(None)

是否有一种pythonic方式来实现我的最后一个API示例？如果没有,你能分享一些关于如何编写类层次结构的想法吗？

Answer 1

这样的事情对你有帮助吗？

from functools import partial
S=partial(SET, Family='ethernet-switching', PortMode='trunk')
S(Interface='ge-0/0/6.0', Vlan=['v100', 'v101', 'v102'])
S(Interface='ge-0/0/7.0', Vlan=['v100', 'v101', 'v102'])
S(Interface='ge-0/0/8.0', Vlan=['v100', 'v101', 'v102'])