http://blog.csdn.net/tpiperatgod/article/details/18375387?utm_source=tuicool
另一个地址：http://neuromancer.sinaapp.com/?p=64
从nova client的入口查看
cat /usr/bin/nova
-
#!/usr/bin/python
# PBR Generated from ‘console_scripts‘
import
fromimport
if:
-
sys.exit(main())
其中导入了novaclient.shell这个文件中导入了main方法，进入novaclient.shell.py查看
-
def
try
:]))
-
except
)
-
print"ERROR: %s"
)
-
.cs = client.Client(options.os_compute_api_version, os_username,
-
.extensions, service_type=service_type,
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cacert=cacert, timeout=timeout)
self.cs是从client中创建出的一个Client实例，进入novaclient.client.py查看这个实例的具体方法
-
def
: ,
-
: ,
-
: ,
-
try
except
.join(version_map.keys())))
-
raise
return
def
return client_class(*args, **kwargs)
用的是v1_1这个版本的api，对应的是novaclient.v1_1.client.py里的Client类
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class
Top-level object to access the OpenStack Compute API.
-
-
Create an instance with your creds::
-
-
>>> client = Client(USERNAME, PASSWORD, PROJECT_ID, AUTH_URL)
-
-
Then call methods on its managers::
-
-
>>> client.servers.list()
-
...
-
>>> client.flavors.list()
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...
-
-
"""
注释里讲了怎么使用python命令行调用nova的client
client里给流入的指令分了很多类，以flavors为例，看nova flavor-list这个命令的流程
-
self)
-
class
Manage :class:`Flavor` resources.
-
"""
-
def, detailed=, is_public=):
-
Get a list of all flavors.
-
-
:rtype: list of :class:`Flavor`.
-
"""
-
-
-
ifnot
] = is_public
-
% urlutils.urlencode(qparams) ifelse<span " <="" span="">
-
<span " <="" span="">
-
if
-
return._list( % (detail, query_string), )
self._list进入novaclient.base.py
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class
Managers interact with a particular type of API (servers, flavors, images,
-
etc.) and provide CRUD operations for them.
-
"""
-
def, api):
-
.api = api
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def, url, response_key, obj_class=, body=):
-
if
.api.client.post(url, body=body)
-
else
.api.client.get(url)
-
ifis:
-
.resource_class
-
-
-
if
try
]
-
except
pass
.completion_cache(, obj_class, mode=):
-
.completion_cache(, obj_class, mode=):
-
return, res, loaded=)
-
forinif res]
novaclient.v1_1.flavors.py里FlavorManager的resource_class = Flavor即class Flavor(base.Resource)
所以最后obj_class为Flavor
调用api的过程：
-
if
.api.client.post(url, body=body)
-
else
.api.client.get(url)
-
通过.api到了nova的api里nova.api.openstack.compute.__init__.py
-
ifis or in
.resources[] = flavors.create_resource()
-
, ,
-
.resources[],
-
: },
-
: })
找到nova.api.openstack.flavors.py
-
@wsgi
def, req):
-
._get_flavors(req)
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return._view_builder.index(req, limited_flavors)
它最后会返回一个存放flavors信息的字典，这些原始数据经过提取和加工，最后在终端被打印出来
nova.api.openstack.compute.views.flavors.py
-
def, func, request, flavors):
-
] forin
._get_collection_links(request,
-
._collection_name,
-
)
-
if
] = flavors_links
-
return flavors_dict
添加一个新的client流程：
功能：快速备份虚拟机，三个参数，虚拟机uuid、备份的名字、备份的描述，调用地方和方法如下：
novaclient.shell.py
class OpenStackComputeShell(object) 的get_subcommand_parser 方法里指定了actions_module
转到novaclient.v1_1.shell.py
增加一个新的方法，装饰器里是需要的参数，有顺序，和执行时的参数顺序一致
-
@utils‘server‘, help=)
-
@utils‘displayname‘
,
-
)
-
@utils‘description‘
,
-
,
-
)
-
def
args.description)
这个功能是加在servers部分里的，转到novaclient.v1_1.servers.py
在ServerManager类里添加
-
def, server, backup_name, backup_description):
-
Backup a server instance quickly.
-
-
:param server: The :class:`Server` (or its ID) to share onto.
-
:param backup_name: Name of the backup image
-
:param backup_description: The backup description
-
"""
: backup_name,
-
: backup_description}
-
-
return._create( % base.getid(server),
-
)
response_key是指返回数据里的key，这里返回的数据是{‘id‘: "*****"}，所以response_key = "id"
因为这个api返回的是一个json字符串，不能通过novaclient.base.py里Manager类里的方法把数据提取出来（它需要字典），于是把return_raw这个参数设置为True
然后就可以在nova的命令行里看到这个新的功能了：nova
backup-instance；使用方法：nova backup-instance <server_id>
<bak_name> <bak_description>
