pbr库是一个使用统一方式管理setuptools包的库。pbr库通过一个setup钩子函数读取并过滤setup.cfg中的数据,以填充默认值并提供更多合理的操作;然后将结果作为参数返回给setup.py。因此,处理Python包安装的大量繁重工作仍然交给setuptools包处理,pbr只为setuptools读取和过滤所需要的参数即可。需要注意的是,pbr并不支持setuptools的easy_install功能,尽管pbr依赖setup_requires,但对于install_requires还是需要手动或使用pip进行安装。本文将详细分析pbr的实现原理和使用方法。
from pbr.hooks import backwards
from pbr.hooks import commands
from pbr.hooks import files
from pbr.hooks import metadata
def setup_hook(config):
"""Filter config parsed from a setup.cfg to inject our defaults."""
metadata_config = metadata.MetadataConfig(config)
metadata_config.run()
backwards.BackwardsCompatConfig(config).run()
commands.CommandsConfig(config).run()
files.FilesConfig(config, metadata_config.get_name()).run()
[metadata]
name = nova
summary = Cloud computing fabric controller
description-file =
README.rst
author = OpenStack
author-email = openstack-dev@lists.openstack.org
home-page = https://docs.openstack.org/nova/latest/
classifier =
Environment :: OpenStack
Intended Audience :: Information Technology
Intended Audience :: System Administrators
License :: OSI Approved :: Apache Software License
Operating System :: POSIX :: Linux
Programming Language :: Python
Programming Language :: Python :: 2
Programming Language :: Python :: 2.7
Programming Language :: Python :: 3
Programming Language :: Python :: 3.5
[global]
setup-hooks =
pbr.hooks.setup_hook
[files]
data_files =
etc/nova =
etc/nova/api-paste.ini
etc/nova/rootwrap.conf
etc/nova/rootwrap.d = etc/nova/rootwrap.d/*
packages =
nova
[entry_points]
oslo.config.opts =
nova.conf = nova.conf.opts:list_opts
oslo.config.opts.defaults =
nova.conf = nova.common.config:set_middleware_defaults
oslo.policy.enforcer =
nova = nova.policy:get_enforcer
oslo.policy.policies =
# The sample policies will be ordered by entry point and then by list
# returned from that entry point. If more control is desired split out each
# list_rules method into a separate entry point rather than using the
# aggregate method.
nova = nova.policies:list_rules
nova.compute.monitors.cpu =
virt_driver = nova.compute.monitors.cpu.virt_driver:Monitor
console_scripts =
nova-api = nova.cmd.api:main
nova-api-metadata = nova.cmd.api_metadata:main
nova-api-os-compute = nova.cmd.api_os_compute:main
nova-cells = nova.cmd.cells:main
nova-compute = nova.cmd.compute:main
nova-conductor = nova.cmd.conductor:main
nova-console = nova.cmd.console:main
nova-consoleauth = nova.cmd.consoleauth:main
nova-dhcpbridge = nova.cmd.dhcpbridge:main
nova-manage = nova.cmd.manage:main
nova-network = nova.cmd.network:main
nova-novncproxy = nova.cmd.novncproxy:main
nova-policy = nova.cmd.policy_check:main
nova-rootwrap = oslo_rootwrap.cmd:main
nova-rootwrap-daemon = oslo_rootwrap.cmd:daemon
nova-scheduler = nova.cmd.scheduler:main
nova-serialproxy = nova.cmd.serialproxy:main
nova-spicehtml5proxy = nova.cmd.spicehtml5proxy:main
nova-status = nova.cmd.status:main
nova-xvpvncproxy = nova.cmd.xvpvncproxy:main
wsgi_scripts =
nova-placement-api = nova.api.openstack.placement.wsgi:init_application
nova-api-wsgi = nova.api.openstack.compute.wsgi:init_application
nova-metadata-wsgi = nova.api.metadata.wsgi:init_application
nova.ipv6_backend =
rfc2462 = nova.ipv6.rfc2462
account_identifier = nova.ipv6.account_identifier
nova.scheduler.host_manager =
host_manager = nova.scheduler.host_manager:HostManager
ironic_host_manager = nova.scheduler.ironic_host_manager:IronicHostManager
nova.scheduler.driver =
filter_scheduler = nova.scheduler.filter_scheduler:FilterScheduler
caching_scheduler = nova.scheduler.caching_scheduler:CachingScheduler
chance_scheduler = nova.scheduler.chance:ChanceScheduler
fake_scheduler = nova.tests.unit.scheduler.fakes:FakeScheduler
[build_sphinx]
all_files = 1
build-dir = doc/build
source-dir = doc/source
warning-is-error = 1
[build_apiguide]
all_files = 1
build-dir = api-guide/build
source-dir = api-guide/source
[egg_info]
tag_build =
tag_date = 0
tag_svn_revision = 0
[compile_catalog]
directory = nova/locale
domain = nova
[update_catalog]
domain = nova
output_dir = nova/locale
input_file = nova/locale/nova.pot
[extract_messages]
keywords = _ gettext ngettext l_ lazy_gettext
mapping_file = babel.cfg
output_file = nova/locale/nova.pot
[wheel]
universal = 1
[extras]
osprofiler =
osprofiler>=1.4.0 # Apache-2.0
接下来,只需要添加一个setup.py安装脚本即可。
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
try:
import multiprocessing # noqa
except ImportError:
pass
setuptools.setup(
setup_requires=['pbr>=2.0.0'],
pbr=True)
在这个脚本中,主要调用了setuptools.setup()方法,需要注意的是,在这个方法中,设置了pbr=True的参数,这就是说在使用setuptools进行安装时,会调用pbr.pbr()方法通过hook函数获取setup.cfg中的配置参数。
python setup.py install