本文介绍如何使用Alibaba Cloud SDK for Python创建NAT网关。

1. 在下载的SDK目录中，打开aliyun-openapi-python-sdk-examples\sdk_examples\examples\natgw文件夹。
2. 使用编辑器打开natgw_quick_start.py文件，根据实际情况配置相关参数，保存退出。
   完整代码示例如下：

   #encoding=utf-8
   import sys
   import json
   import time
   
   from aliyunsdkcore.acs_exception.exceptions import ServerException, ClientException
   from aliyunsdkvpc.request.v20160428 import CreateNatGatewayRequest
   from aliyunsdkvpc.request.v20160428 import DeleteNatGatewayRequest
   from aliyunsdkvpc.request.v20160428 import DescribeNatGatewaysRequest
   from sdk_lib.sdk_vpc import Vpc
   from sdk_lib.sdk_vswitch import VSwitch
   from sdk_lib.common_util import CommonUtil
   from sdk_lib.check_status import CheckStatus
   from sdk_lib.exception import ExceptionHandler
   from sdk_lib.consts import *
   
   client = AcsClient(
            '<your-access-key-id>',     # 您的AccessKey ID
            '<your-access-key-secret>', # 您的AccessKey Secret
            '<your-region-id>')         # 您的地域ID
   
   
   class NatGateway(object):
       def __init__(self, client):
           self.client = client
   
       def create_nat_gateway(self, params):
           """
           create_nat_gateway: 创建nat gateway
           """
           try:
               request = CreateNatGatewayRequest.CreateNatGatewayRequest()
               request.set_VpcId(params['vpc_id'])
               response = client.do_action_with_exception(request)
               response_json = json.loads(response)
               # 判断Nat Gateway状态是否可用
               if CheckStatus.check_status(TIME_DEFAULT_OUT, DEFAULT_TIME,
                                           self.describe_nat_gateway_status,
                                           AVAILABLE, response_json['NatGatewayId']):
                   return response_json
           except ServerException as e:
               ExceptionHandler.server_exception(e)
           except ClientException as e:
               ExceptionHandler.client_exception(e)
   
       def describe_nat_gateway(self, nat_gateway_id):
           """
           describe_nat_gateway: 查询指定地域已创建的Nat Gateway的信息
           """
           try:
               request = DescribeNatGatewaysRequest.DescribeNatGatewaysRequest()
               request.set_NatGatewayId(nat_gateway_id)
               response = client.do_action_with_exception(request)
               response_json = json.loads(response)
               return response_json
           except ServerException as e:
               ExceptionHandler.server_exception(e)
           except ClientException as e:
               ExceptionHandler.client_exception(e)
   
       def delete_nat_gateway(self, params):
           """
           delete_nat_gateway: 删除Nat Gateway
           """
           try:
               request = DeleteNatGatewayRequest.DeleteNatGatewayRequest()
               request.set_NatGatewayId(params['nat_gateway_id'])
               response = client.do_action_with_exception(request)
               response_json = json.loads(response)
               # 判断Nat Gateway状态是否可用
               if CheckStatus.check_status(TIME_DEFAULT_OUT, DEFAULT_TIME * 5,
                                           self.describe_nat_gateway_status,
                                           '', params['nat_gateway_id']):
                   return response_json
           except ServerException as e:
               ExceptionHandler.server_exception(e)
           except ClientException as e:
               ExceptionHandler.client_exception(e)
   
       def describe_nat_gateway_status(self, nat_gateway_id):
           """
           describe_nat_gateway_status: 查询指定地域已创建的Nat Gateway的状态
           """
           response = self.describe_nat_gateway(nat_gateway_id)
           if len(response["NatGateways"]["NatGateway"]) == 0:
               return ''
           return response["NatGateways"]["NatGateway"][0]['Status']
   
   
   def main():
       vpc = Vpc(client)
       vswitch = VSwitch(client)
       nat_gateway = NatGateway(client)
   
       params = {}
   
       # 创建VPC
       vpc_json = vpc.create_vpc()
       CommonUtil.log("create_vpc", vpc_json)
   
       # 创建VSwitch
       params['vpc_id'] = vpc_json['VpcId']
       params['zone_id'] = "cn-shanghai-a"
       params['cidr_block'] = "172.16.1.0/24"
       vswitch_json = vswitch.create_vswitch(params)
       CommonUtil.log("create_vswitch", vswitch_json)
   
       # 创建Nat Gateway
       nat_gateway_json = nat_gateway.create_nat_gateway(params)
       CommonUtil.log("create_nat_gateway", nat_gateway_json)
   
       # 查询Nat Gateway
       params['nat_gateway_id'] = nat_gateway_json['NatGatewayId']
       nat_gateway_json = nat_gateway.describe_nat_gateway(params['nat_gateway_id'])
       CommonUtil.log("describe_nat_gateway", nat_gateway_json)
   
       # 删除Nat Gateway
       nat_gateway_json = nat_gateway.delete_nat_gateway(params)
       CommonUtil.log("delete_nat_gateway", nat_gateway_json)
   
       # 删除VSwitch
       params['vswitch_id'] = vswitch_json['VSwitchId']
       vswitch_json = vswitch.delete_vswitch(params)
       CommonUtil.log("delete_vswitch", vswitch_json)
   
       # 删除VPC
       vpc_json = vpc.delete_vpc(params)
       CommonUtil.log("delete_vpc", vpc_json)
   
   
   if __name__ == "__main__":
       sys.exit(main())

3. 进入natgw_quick_start.py所在的目录，执行如下命令，创建NAT网关。

   python natgw_quick_start.py

---------------------------create_vpc---------------------------
{
  "ResourceGroupId": "rg-acfmxaz****",
  "RouteTableId": "vtb-uf6wzp25d8lkb****",
  "VRouterId": "vrt-uf6di7voecmyq****",
  "VpcId": "vpc-uf63cqupghmk1****",
  "RequestId": "97D36E19-F789-424F-A473-660D63EF8CF9"
}

---------------------------create_vswitch---------------------------
{
  "VSwitchId": "vsw-uf6fovepnk4****",
  "RequestId": "18DA0E81-34A6-4877-9771-E2C4EEEBADD1"
}

---------------------------create_nat_gateway---------------------------
{
  "NatGatewayId": "ngw-uf6mfrcmzktst****",
  "BandwidthPackageIds": {
    "BandwidthPackageId": []
  },
  "ForwardTableIds": {
    "ForwardTableId": [
      "ftb-uf6411str8n9s****"
    ]
  },
  "RequestId": "B1F791C8-73B1-46C5-8A20-726A615BC627",
  "SnatTableIds": {
    "SnatTableId": [
      "stb-uf6t4eijvq3ae****"
    ]
  }
}

---------------------------describe_nat_gateway---------------------------
{
  "TotalCount": 1,
  "PageNumber": 1,
  "RequestId": "1F9303B1-4024-4A92-B67E-FB6BE1DC76D1",
  "PageSize": 10,
  "NatGateways": {
    "NatGateway": [
      {
        "Status": "Available",
        "BandwidthPackageIds": {
          "BandwidthPackageId": []
        },
        "VpcId": "vpc-uf63cqupghmk1****",
        "Description": "",
        "ForwardTableIds": {
          "ForwardTableId": [
            "ftb-uf6411str8n9s****"
          ]
        },
        "IpLists": {
          "IpList": []
        },
        "BusinessStatus": "Normal",
        "RegionId": "cn-shanghai",
        "CreationTime": "2019-04-24T09:09:12Z",
        "NatGatewayId": "ngw-uf6mfrcmzktst****",
        "SnatTableIds": {
          "SnatTableId": [
            "stb-uf6t4eijvq3ae****"
          ]
        },
        "AutoPay": false,
        "InstanceChargeType": "PostPaid",
        "ExpiredTime": "",
        "Spec": "Small",
        "Name": ""
      }
    ]
  }
}

---------------------------delete_nat_gateway---------------------------
{
  "RequestId": "A0B71FE4-4756-4D91-899E-1DFA52D8615E"
}

---------------------------delete_vswitch---------------------------
{
  "RequestId": "F224307E-3DE4-4415-AE19-DDCF24695462"
}

---------------------------delete_vpc---------------------------
{
  "RequestId": "1BFFCBC3-7F83-436C-96E9-CA4A620072DA"
}