This topic describes how to use Alibaba Cloud SDK for Python to create a NAT gateway.

Prerequisites

Before you use Alibaba Cloud SDK for Python, make sure that the following requirements are met:
  • An Alibaba Cloud account and the AccessKey pair are obtained. You can create and view your AccessKey pair on the Security Management page of the Alibaba Cloud Management Console.
  • Make sure that Alibaba Cloud SDK for Python is installed. For more information, see aliyun-python-sdk-vpc 3.0.12.
  • The VPC Python example library is downloaded.
    Go to the directory where the setup.py file is stored, and run the following command to initialize the environment: 
    python setup.py install

Background information

The code sample in this topic includes the following operations:
  1. Create a virtual private cloud (VPC) in the China (Shanghai) region.
  2. Create a vSwitch in the VPC.
  3. Create a NAT gateway for the VPC.
  4. Query the NAT gateway.
  5. Delete the NAT gateway.
  6. Delete the vSwitch.
  7. Delete the VPC.

Procedure

  1. In the directory of downloaded SDK files, open the aliyun-openapi-python-sdk-examples\sdk_examples\examples\natgw folder.
  2. Open the natgw_quick_start.py file in your text editor. Set the required parameters, save the configurations, and then exit the editor.
    The following sample code is displayed: 
    #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>',     # Your AccessKey ID.
         '<your-access-key-secret>', # Your AccessKey secret.
         '<your-region-id>')         # Your region ID.


class NatGateway(object):
    def __init__(self, client):
        self.client = client

    def create_nat_gateway(self, params):
        """
        create_nat_gateway: Create a NAT gateway.
        """
        try:
            request = CreateNatGatewayRequest.CreateNatGatewayRequest()
            request.set_VpcId(params['vpc_id'])
            response = client.do_action_with_exception(request)
            response_json = json.loads(response)
            # Check whether the NAT gateway is in the Available state.
            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: Query information about NAT gateways in the specified region.
        """
        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: # Delete the 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)
            # Check whether the NAT gateway is in the Available state.
            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: Query status about NAT gateways in the specified region.
        """
        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 = {}

    # Create a VPC.
    vpc_json = vpc.create_vpc()
    CommonUtil.log("create_vpc", vpc_json)

    # Create a 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)

    # Create a NAT gateway.
    nat_gateway_json = nat_gateway.create_nat_gateway(params)
    CommonUtil.log("create_nat_gateway", nat_gateway_json)

    # Query the 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)

    # Delete the NAT gateway.
    nat_gateway_json = nat_gateway.delete_nat_gateway(params)
    CommonUtil.log("delete_nat_gateway", nat_gateway_json)

    # Delete the vSwitch.
    params['vswitch_id'] = vswitch_json['VSwitchId']
    vswitch_json = vswitch.delete_vswitch(params)
    CommonUtil.log("delete_vswitch", vswitch_json)

    # Delete the VPC.
    vpc_json = vpc.delete_vpc(params)
    CommonUtil.log("delete_vpc", vpc_json)


if __name__ == "__main__":
    sys.exit(main())
  3. Go to the directory where the natgw_quick_start.py file is stored, and run the following command to create a NAT gateway: 
    python natgw_quick_start.py

Result

The following output is returned: 
---------------------------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"
}