文前说明
作为码农中的一员，需要不断的学习，我工作之余将一些分析总结和学习笔记写成博客与大家一起交流，也希望采用这种方式记录自己的学习之旅。
本文仅供学习交流使用，侵权必删。
不用于商业目的，转载请注明出处。
分析整理的版本为 Ovirt 3.4.5 版本。
命令使用方式：engine-upgrade-check [options]
Options:
-h, --help show this help message and exit
-q, --quiet quiet mode
命令采用了 python 方式进行实现。
- 主要调用了 otopi。
otopi
otopi 是 oVirt 面向任务的可插拔安装/实施。是用于安装独立插件的系统组件。插件只需提供简单的添加的安装功能而无需复杂的事务管理。
使用方式：otopi [variables]
variables ::= name=type:value variables | APPEND:name=type:value | ''
type ::= none | bool | int | str | multi-str
APPEND: prefix appends as colon list string.
CUSTOMIZATION
-------------
Set the following environment:
DIALOG/customization=bool:True
This will trigger command-line prompt before validation and
before termination.
Refer to README.dialog for more information.
FILES
-----
CONFIGURATION
Configuration files used to override the environment.
System environment:
OTOPI_CONFIG
Environment:
CORE/configFileName
Default:
/etc/otopi.conf
Config files to be read:
@configFileName@
@[email protected]/*.conf (sorted)
Structure:
[environment:default]
key=type:value
[environment:init]
key=type:value
[environment:override]
key=type:value
[environment:enforce]
key=type:value
default is applied during setup without override.
init is applied during setup with override.
override is applied before customization with override.
enforce is applied after customization with override.
type ::= none | bool | int | str | multi-str
ENVIRONMENT
-----------
Refer to README.environment
UNPRIVILEDGE EXECUTION
----------------------
Using sudo it is possible to escalate privilege. Use the following
configuration:
/etc/sudoers.d/50-otopi.conf
Defaults:user1 !requiretty
user1 ALL=(ALL) NOPASSWD: /bin/sh
COMPATIBILITY
-------------
- Python-2.6
- Python-2.7
- Python-3.2
- 调用 otopi 中的 miniyum 检查是否有更新。
myum = miniyum.MiniYum(
sink=(
None if options.quiet
else _MyMiniYumSink()
),
disabledPlugins=('versionlock',),
)
with myum.transaction():
myum.update(
packages=setup_packages,
)
if myum.buildTransaction():
exit = 0
......
- 查看 otopi 系统组件的源码，可以看出 miniyum 是读取 yum 源，从 yum 仓库中判断是否有新的包。
with miniyum.transaction():
miniyum.remove(('cman',), ignoreErrors=True)
miniyum.install(('qemu-kvm-tools',))
miniyum.install(('vdsm', 'vdsm-client'))
miniyum.update(('vdsm', 'vdsm-client'))
if miniyum.buildTransaction():
miniyumsink.info('Transaction Summary:')
for p in miniyum.queryTransaction():
miniyumsink.info(' %s - %s' % (
p['operation'],
p['display_name']
))
miniyum.processTransaction()
......
def update(self, packages, **kwargs):
"""Update packages.
Keyword arguments:
packages -- packages to install.
ignoreErrors - to ignore errors, will return False
"""
return self._queue(
'update',
lambda h: h.available,
self._yb.update,
packages,
**kwargs
)