python entry points 例子

 pbr的介绍不多， http://ju.outofmemory.cn/entry/156745

 

$ mkdir entry_test; cd entry_test; git init

$ mkdir  -p mypackage/api/v1/

$ touch mypackage/__init__.py; touch mypackage/api/__init__.py; touch mypackage/api/v1/__init__.py;

$ tree mypackage

.
├── mypackage
│   ├── api
│   │   ├── __init__.py
│   │   └── v1
│   │       ├── databases.py
│   │       ├── hello.py
│   │       ├── __init__.py
│   ├── __init__.py
├── setup.cfg
└── setup.py

$ cat mypackage/api/v1/databases.py

def main():

    print "this is databases main"

 

$ cat mypackage/api/v1/hello.py

def main():

    print "this is hello main"

 

$ cat  setup.cfg

[metadata]

name = mypackage 

version = 12.0.0

summary = Cloud computing fabric controller



[files]

packages =

    mypackage 



[entry_points]

mypackage.api.v1 = 

    databases = mypackage.api.v1.databases:main

    hello = mypackage.api.v1.hello:main



[wheel]

universal = 1



[pbr]

autodoc_index_modules = 0

warnerrors = true

$ cat setup.py

import setuptools



# In python < 2.7.4, a lazy loading of package `pbr` will break

# setuptools if some other modules registered functions in `atexit`.

# solution from: http://bugs.python.org/issue15881#msg170215



setuptools.setup(

    name='mypackage',

    packages=['mypackage'],

    package_dir={'mypackage': 'mypackage'},

    setup_requires=['pbr'],

    pbr=True,

    entry_points={

        'mypackage.api.v1':[

            'databases=mypackage.api.v1.databases:main',

            'hello=mypackage.api.v1.hello:main',

            ],

    }

)

 

调用方法1：

令贤的blog介绍 stevedore： http://blog.csdn.net/lynn_kong/article/details/9704413

opensatck 社区介绍stevedore   http://docs.openstack.org/developer/stevedore/tutorial/index.html 

教程：  https://github.com/openstack/stevedore/tree/master/doc/source/tutorial

from stevedore import extension



def test_detect_plugins():

    em = extension.ExtensionManager('mypackage.api.v1')

    names = sorted(em.names())

    print names

    em1 = extension.ExtensionManager('mypackage.api.v1')

    eps1 = [ext.plugin for ext in em1]  #plugin是被映射的函数，用于调用

    em1 = extension.ExtensionManager('mypackage.api.v1')

    eps1 = [ext.entry_point for ext in em1]

调用方法2：

import pkg_resources



def run_entry_point(*argv):

    group = 'mypackage.api.v1'

    for entrypoint in pkg_resources.iter_entry_points(group=group):

        # Grab the function that is the actual plugin.

        plugin = entrypoint.load()

        print plugin

        type(plugin)

        plugin(*argv)

 

调用方法3：

from pkg_resources import load_entry_point

load_entry_point('mypackage', 'mypackage.api.v1', 'database')()

 

在我的test 例子中需要导入pbr 才能工作，否则有些源代码打包不了。 

http://blog.oddbit.com/2014/09/27/integrating-custom-code-with-n/

https://github.com/larsks/demo_nova_hooks

没有导入pbr， 也可以, 需要研究。