详解通过API管理或定制开发ECS实例

弹性管理 ECS 实例

获取 RAM 子账号 AK 密钥

使用API管理ECS实例，您需要能访问ECS资源的API密钥（AccessKey ID 和 AccessKey Secret）。为了保证云服务的安全，您需要创建一个能访问ECS资源的RAM用户，获取该用户的AccessKey密钥，并使用这个RAM用户和API管理ECS实例。

以下是获取RAM用户AccessKey密钥的操作步骤：

创建RAM用户并获取AccessKey密钥。

直接给RAM用户授权，授予RAM用户 管理云服务器服务(ECS)的权限。

安装 ECS Python SDK

首先确保您已经具备Python的Runtime，本文中使用的Python版本为2.7+。

pip install aliyun-python-sdk-ecs

如果提示您没有权限，请切换sudo继续执行。

sudo pip install aliyun-python-sdk-ecs

本文使用的SDK版本为 2.1.2。

Hello Alibaba Cloud

创建文件 hello_ecs_api.py。为了使用SDK，首先实例化AcsClient对象，这里需要RAM用户的AccessKey ID和AccessKey Secret。

AccessKey ID和AccessKey Secret是RAM用户访问阿里云ECS服务API的密钥，具有该账户完全的权限，请妥善保管。

from aliyunsdkcore import client
from aliyunsdkecs.request.v20140526.DescribeInstancesRequest import DescribeInstancesRequest
from aliyunsdkecs.request.v20140526.DescribeRegionsRequest import DescribeRegionsRequest
clt = client.AcsClient('Your Access Key Id', 'Your Access Key Secrect', 'cn-beijing')

完成实例化后可以进行第一个应用的开发。查询当前账号支持的地域列表。具体的文档参见 查询可用地域列表。

def hello_aliyun_regions():
  request = DescribeRegionsRequest()
  response = _send_request(request)
  region_list = response.get('Regions').get('Region')
  assert response is not None
  assert region_list is not None
  result = map(_print_region_id, region_list)
  logging.info("region list: %s", result)
def _print_region_id(item):
  region_id = item.get("RegionId")
  return region_id
def _send_request(request):
  request.set_accept_format('json')
  try:
    response_str = clt.do_action(request)
    logging.info(response_str)
    response_detail = json.loads(response_str)
    return response_detail
  except Exception as e:
    logging.error(e)
hello_aliyun_regions()

在命令行运行 python hello_ecs_api.py 会得到当前支持的 Region列表。类似的输出如下：

[u'cn-shenzhen', u'ap-southeast-1', u'cn-qingdao', u'cn-beijing', u'cn-shanghai', 
u'us-east-1', u'cn-hongkong', u'me-east-1', u'ap-southeast-2', u'cn-hangzhou', u'eu-central-1',
 u'ap-northeast-1', u'us-west-1']

查询当前的 Region 下的 ECS 实例列表

查询实例列表和查询 Region 列表非常类似，替换入参对象为DescribeInstancesRequest 即可，更多的查询参数参考 查询实例列表。

def list_instances():
  request = DescribeInstancesRequest()
  response = _send_request(request)
  if response is not None:
    instance_list = response.get('Instances').get('Instance')
    result = map(_print_instance_id, instance_list)
    logging.info("current region include instance %s", result)
def _print_instance_id(item):
  instance_id = item.get('InstanceId');
  return instance_id

输出结果为如下：

current region include instance [u'i-****', u'i-****'']

更多的API参考 ECS API 概览，您可以尝试作一个 查询磁盘列表，将实例的参数替换为 DescribeDisksRequest。

完整代码示例

以上操作完整的代码示例如下所示。

# coding=utf-8
# if the python sdk is not install using 'sudo pip install aliyun-python-sdk-ecs'
# if the python sdk is install using 'sudo pip install --upgrade aliyun-python-sdk-ecs'
# make sure the sdk version is 2.1.2, you can use command 'pip show aliyun-python-sdk-ecs' to check
import json
import logging
from aliyunsdkcore import client
from aliyunsdkecs.request.v20140526.DescribeInstancesRequest import DescribeInstancesRequest
from aliyunsdkecs.request.v20140526.DescribeRegionsRequest import DescribeRegionsRequest
# configuration the log output formatter, if you want to save the output to file,
# append ",filename='ecs_invoke.log'" after datefmt.
logging.basicConfig(level=logging.INFO,
          format='%(asctime)s %(filename)s[line:%(lineno)d] %(levelname)s %(message)s',
          datefmt='%a, %d %b %Y %H:%M:%S')
clt = client.AcsClient('Your Access Key Id', 'Your Access Key Secrect', 'cn-beijing')
# sample api to list aliyun open api.
def hello_aliyun_regions():
  request = DescribeRegionsRequest()
  response = _send_request(request)
  if response is not None:
    region_list = response.get('Regions').get('Region')
    assert response is not None
    assert region_list is not None
    result = map(_print_region_id, region_list)
    logging.info("region list: %s", result)
# output the instance owned in current region.
def list_instances():
  request = DescribeInstancesRequest()
  response = _send_request(request)
  if response is not None:
    instance_list = response.get('Instances').get('Instance')
    result = map(_print_instance_id, instance_list)
    logging.info("current region include instance %s", result)
def _print_instance_id(item):
  instance_id = item.get('InstanceId');
  return instance_id
def _print_region_id(item):
  region_id = item.get("RegionId")
  return region_id
# send open api request
def _send_request(request):
  request.set_accept_format('json')
  try:
    response_str = clt.do_action(request)
    logging.info(response_str)
    response_detail = json.loads(response_str)
    return response_detail
  except Exception as e:
    logging.error(e)
if __name__ == '__main__':
  logging.info("Hello Aliyun OpenApi!")
  hello_aliyun_regions()
  list_instances()