为了更方便的实现弹性的资源创建，方便您一次运行多台ECS按量实例来完成应用的开发和部署，我们开放了ECS的批量创建实例接口RunInstances。和目前的CreateInstance相比，RunInstances有下面的优点：

• 单次可以最多创建100台实例，避免重复调用。
• 批量提交一定的ECS实例数目，如果库存不足，则直接失败，避免您创建的实例数目不能满足需求而额外产生费用。
• 实例创建之后，会自动的开始Start，实例会变成Starting状态，直至Running，不需要您调用Start的操作。
• 创建实例的时候指定了InternetMaxBandwidthOut,则自动为您分配公网IP，不需要您再调用分配IP的操作。
• 您可以在创建的时候指定自动释放时间，自动释放，不需要您再额外设置自动释放时间。
• 您也可以一次创建100台的SpotInstance，充分满足您的弹性需求。
• 创建的参数保持和CreateInstance保持兼容，提供了Amount来设定创建的个数，提供了AutoReleaseTime来设定自动释放时间。
• 创建返回一个InstanceIdSets会记录相关的InstanceIds，您只需要根据实例ID轮询实例状态即可。

下文以Python为示例，其他的版本SDK都需要大于4.4.3即可。

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4.4.3, 如果您使用是旧版本的sdk，需要你更新下。

批量创建实例

首先创建RunInstancesRequest的实例，然后填入相关需要的参数即可。

下面的例子创建了2台实例，并且添加了自动每隔10秒钟检查一次实例的运行状态。直到实例状态变成Running结束创建流程。

# your access key Id
ak_id = "YOU_ACCESS_KEY_ID"
# your access key secret
ak_secret = "YOU_ACCESS_SECRET"
region_id = "cn-beijing"

# your expected instance type
instance_type = "ecs.n4.small"
# 选择的vswitchId
vswitch_id = "vws-xxxxx"
# 使用的镜像信息
image_id = "centos_7_03_64_20G_alibase_20170818.vhd"
# 当前vpc类型的安全组
security_group_id = "sg-xxxxx"

# instance number to lunch, support 1-100, default value is 100
amount = 2;

# instance auto delete time 按照 ISO8601 标准表示，并需要使用 UTC 时间。格式为 yyyy-MM-ddTHH:mm:ssZ 。 最短在当前时间之后半小时。最长不能超过当前时间起三年
auto_release_time = "2017-12-05T22:40:00Z"

clt = client.AcsClient(ak_id, ak_secret, 'cn-beijing')


# create instance automatic running
def batch_create_instance():
    request = build_request()
    request.set_Amount(amount)
    _execute_request(request)


def _execute_request(request):
    response = _send_request(request)
    if response.get('Code') is None:
        instance_ids = response.get('InstanceIdSets').get('InstanceIdSet')
        running_amount = 0
        while running_amount < amount:
            time.sleep(10)
            running_amount = check_instance_running(instance_ids)
    print("ecs instance %s is running", instance_ids)


def check_instance_running(instance_ids):
    request = DescribeInstancesRequest()
    request.set_InstanceIds(json.dumps(instance_ids))
    response = _send_request(request)
    if response.get('Code') is None:
        instances_list = response.get('Instances').get('Instance')
        running_count = 0
        for instance_detail in instances_list:
            if instance_detail.get('Status') == "Running":
                running_count += 1
        return running_count


def build_request():
    request = RunInstancesRequest()
    request.set_ImageId(image_id)
    request.set_VSwitchId(vswitch_id)
    request.set_SecurityGroupId(security_group_id)
    request.set_InstanceName("Instance12-04")
    request.set_InstanceType(instance_type)
    return request


# 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)

批量创建实例并自动分配公网IP

相比上面的代码，我们只需要添加一行属性，指定公网的带宽即可。下面的例子中我们默认给实例都分配了1M的按流量带宽。

# create instance with public ip.
def batch_create_instance_with_public_ip():
    request = build_request()
    request.set_Amount(amount)
    request.set_InternetMaxBandwidthOut(1)
    _execute_request(request)

批量创建实例并自动设置自动释放时间

相比上面的代码，我们只需要添加一行属性，实例的自动释放时间即可。 自动释放时间按照 ISO8601 标准表示，并需要使用 UTC 时间。格式为 yyyy-MM-ddTHH:mm:ssZ 。 最短在当前时间之后半小时。最长不能超过当前时间起三年。

# create instance with auto release time.
def batch_create_instance_with_auto_release_time():
    request = build_request()
    request.set_Amount(amount)
    request.set_AutoReleaseTime(auto_release_time)
    _execute_request(request)

完整代码如下

#  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 4.4.3, you can use command 'pip show aliyun-python-sdk-ecs' to check

import json
import logging
import time

from aliyunsdkcore import client
from aliyunsdkecs.request.v20140526.DescribeInstancesRequest import DescribeInstancesRequest
from aliyunsdkecs.request.v20140526.RunInstancesRequest import RunInstancesRequest

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')

# your access key Id
ak_id = "YOU_ACCESS_KEY_ID"
# your access key secret
ak_secret = "YOU_ACCESS_SECRET"
region_id = "cn-beijing"

# your expected instance type
instance_type = "ecs.n4.small"
# 选择的vswitchId
vswitch_id = "vws-xxxxx"
# 使用的镜像信息
image_id = "centos_7_03_64_20G_alibase_20170818.vhd"
# 当前vpc类型的安全组
security_group_id = "sg-xxxxx"

# instance number to lunch, support 1-100, default value is 100
amount = 2;

# instance auto delete time 按照 ISO8601 标准表示，并需要使用 UTC 时间。格式为 yyyy-MM-ddTHH:mm:ssZ 。 最短在当前时间之后半小时。最长不能超过当前时间起三年
auto_release_time = "2017-12-05T22:40:00Z"

clt = client.AcsClient(ak_id, ak_secret, 'cn-beijing')


# create instance automatic running
def batch_create_instance():
    request = build_request()
    request.set_Amount(amount)
    _execute_request(request)


# create instance with public ip.
def batch_create_instance_with_public_ip():
    request = build_request()
    request.set_Amount(amount)
    request.set_InternetMaxBandwidthOut(1)
    _execute_request(request)


# create instance with auto release time.
def batch_create_instance_with_auto_release_time():
    request = build_request()
    request.set_Amount(amount)
    request.set_AutoReleaseTime(auto_release_time)
    _execute_request(request)


def _execute_request(request):
    response = _send_request(request)
    if response.get('Code') is None:
        instance_ids = response.get('InstanceIdSets').get('InstanceIdSet')
        running_amount = 0
        while running_amount < amount:
            time.sleep(10)
            running_amount = check_instance_running(instance_ids)
    print("ecs instance %s is running", instance_ids)


def check_instance_running(instance_ids):
    request = DescribeInstancesRequest()
    request.set_InstanceIds(json.dumps(instance_ids))
    response = _send_request(request)
    if response.get('Code') is None:
        instances_list = response.get('Instances').get('Instance')
        running_count = 0
        for instance_detail in instances_list:
            if instance_detail.get('Status') == "Running":
                running_count += 1
        return running_count


def build_request():
    request = RunInstancesRequest()
    request.set_ImageId(image_id)
    request.set_VSwitchId(vswitch_id)
    request.set_SecurityGroupId(security_group_id)
    request.set_InstanceName("Instance12-04")
    request.set_InstanceType(instance_type)
    return request


# 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__':
    print "hello ecs batch create instance"
    # batch_create_instance()
    # batch_create_instance_with_public_ip()
    # batch_create_instance_with_auto_release_time()

通过RunInstances将简化您的资源创建和运行管理。更多的需求您可以留言或者工单提交对我们的反馈。谢谢！