创建SNAT条目 - 专有网络 VPC

本文介绍如何使用Alibaba Cloud SDK for Python创建SNAT条目。

前提条件

在使用Alibaba Cloud SDK for Python前，您需要完成以下准备工作：

您需要一个阿里云账号和访问密钥（AccessKey）。请在阿里云控制台中的AccessKey管理页面上创建和查看您的AccessKey。
确保您已经安装了Alibaba Cloud SDK for Python，请参见aliyun-python-sdk-vpc 3.0.12。
下载阿里云专有网络Python SDK场景示例的VPC Python Example库。
进入setup.py所在的目录，执行以下命令，完成环境初始化配置。
```
python setup.py install
```

背景信息

本文代码示例中包含以下操作：

在华东2上海地域创建一个VPC。
在新建的VPC下创建一个VSwitch。
在新建的VPC下创建一个NAT网关。
在华东2上海地域创建一个EIP。
将创建的EIP绑定到NAT网关。
创建SNAT条目。
查询绑定到NAT网关的EIP。
查询NAT网关。
删除SNAT条目。
将EIP与NAT网关解绑。
删除NAT网关。
释放EIP。
删除VSwitch。
删除VPC。

操作步骤

在下载的SDK目录中，打开aliyun-openapi-python-sdk-examples\sdk_examples\examples\natgw文件夹。

使用编辑器打开natgw_snat.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 aliyunsdkvpc.request.v20160428 import CreateSnatEntryRequest
from aliyunsdkvpc.request.v20160428 import DescribeSnatTableEntriesRequest
from aliyunsdkvpc.request.v20160428 import DeleteSnatEntryRequest
from sdk_lib.sdk_vpc import Vpc
from sdk_lib.sdk_vswitch import VSwitch
from sdk_lib.sdk_eip import Eip
from sdk_lib.sdk_cbwp import CommonBandwidthPackage
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 = ACS_CLIENT = AcsClient(
    'accessKeyId',
    'accessSecret',
    'RegionId'
    #timeout = 35
)


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 create_snat_entry(self, params):
        """
        describe_snat: 创建snat entry
        """
        try:
            request = CreateSnatEntryRequest.CreateSnatEntryRequest()
            request.set_SnatTableId(params['snat_table_id'])
            request.set_SourceVSwitchId(params['vswitch_id'])
            request.set_SnatIp(params['snat_ip'])
            response = client.do_action_with_exception(request)
            response_json = json.loads(response)
            # 判断Snat Entry状态是否可用
            if CheckStatus.check_status(TIME_DEFAULT_OUT, DEFAULT_TIME,
                                        self.describe_snat_status,
                                        AVAILABLE, params['snat_table_id']):
                return response_json
        except ServerException as e:
            ExceptionHandler.server_exception(e)
        except ClientException as e:
            ExceptionHandler.client_exception(e)

    def describe_snat(self, snat_table_id):
        """
        describe_snat: 查询指定地域已创建的snat的信息l
        """
        try:
            request = DescribeSnatTableEntriesRequest.DescribeSnatTableEntriesRequest()
            request.set_SnatTableId(snat_table_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 describe_snat_status(self, snat_table_id):
        """
        describe_snat_status: 查询指定地域已创建的snat的状态
        """
        response = self.describe_snat(snat_table_id)
        if len(response["SnatTableEntries"]["SnatTableEntry"]) == 0:
            return ''
        return response["SnatTableEntries"]["SnatTableEntry"][0]['Status']

    def delete_snat_entry(self, params):
        """
        delete_snat_entry: 删除snat entry
        """
        try:
            request = DeleteSnatEntryRequest.DeleteSnatEntryRequest()
            request.set_SnatTableId(params['snat_table_id'])
            request.set_SnatEntryId(params['snat_entry_id'])
            response = client.do_action_with_exception(request)
            response_json = json.loads(response)
            # 判断Snat Entry状态是否可用
            if CheckStatus.check_status(TIME_DEFAULT_OUT, DEFAULT_TIME * 5,
                                        self.describe_snat_status,
                                        '', params['snat_table_id']):
                return response_json
        except ServerException as e:
            ExceptionHandler.server_exception(e)
        except ClientException as e:
            ExceptionHandler.client_exception(e)


def main():
    vpc = Vpc(client)
    vswitch = VSwitch(client)
    eip = Eip(client)
    cbwp = CommonBandwidthPackage(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-hangzhou-d"
    params['cidr_block'] = "172.16.1.0/24"
    vswitch_json = vswitch.create_vswitch(params)
    CommonUtil.log("create_vswitch", vswitch_json)
    params['vswitch_id'] = vswitch_json['VSwitchId']

    # 创建natgw
    nat_gateway_json = nat_gateway.create_nat_gateway(params)
    CommonUtil.log("create_nat_gateway", nat_gateway_json)

    # 创建EIP
    eip_response_json = eip.allocate_eip_address(params)
    CommonUtil.log("allocate_eip_address", eip_response_json)
    params['allocation_id'] = eip_response_json["AllocationId"]
    params['snat_ip'] = eip_response_json['EipAddress']

    # 绑定EIP到NAT网关
    params['instance_id'] = nat_gateway_json['NatGatewayId']
    params['allocation_id'] = eip_response_json["AllocationId"]
    params['instance_type'] = 'Nat'
    eip_response_json = eip.associate_eip_address(params)
    CommonUtil.log("associate_eip_address eip", eip_response_json)

    # 创建snat entry
    params['snat_table_id'] = nat_gateway_json['SnatTableIds']['SnatTableId'][0]
    snat_entry_json = nat_gateway.create_snat_entry(params)
    CommonUtil.log("create_snat_entry", snat_entry_json)

    # 查询EIP
    eip_response_json = eip.describe_eip_address(params['allocation_id'])
    CommonUtil.log("describe_eip_address", eip_response_json)

    # 查询natgw
    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snat entry
    params['snat_entry_id'] = snat_entry_json['SnatEntryId']
    snat_entry_json = nat_gateway.delete_snat_entry(params)
    CommonUtil.log("delete_snat_entry", snat_entry_json)

    # 解绑EIP
    eip_response_json = eip.unassociate_eip_address(params)
    CommonUtil.log("unassociate_eip_address nat", eip_response_json)

    # 删除natgw
    nat_gateway_json = nat_gateway.delete_nat_gateway(params)
    CommonUtil.log("delete_nat_gateway", nat_gateway_json)

    # 释放EIP
    eip_response_json = eip.release_eip_address(params)
    CommonUtil.log("release_eip_address", eip_response_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())

进入natgw_snat.py所在的目录，执行以下命令，创建SNAT条目。
```
python natgw_snat.py
```

执行结果

系统回显结果如下：

---------------------------create_vpc---------------------------
{
  "ResourceGroupId": "rg-acfmxazxxxxxxxx",
  "RouteTableId": "vtb-uf6a8ccj9ne58xxxxxxxx",
  "VRouterId": "vrt-uf6qqqaf1o1ptxxxxxxxx",
  "VpcId": "vpc-uf6hxer3h07wgxxxxxxxx",
  "RequestId": "8F483A7B-8A38-47ED-85BD-1E83C075AEA4"
}

---------------------------create_vswitch---------------------------
{
  "VSwitchId": "vsw-uf6lbov9tyetqxxxxxxxx",
  "RequestId": "2EE2E11B-EF60-4C88-BE2A-F45517290B31"
}

---------------------------create_nat_gateway---------------------------
{
  "NatGatewayId": "ngw-uf6l3c3rswubuxxxxxxxx",
  "BandwidthPackageIds": {
    "BandwidthPackageId": []
  },
  "ForwardTableIds": {
    "ForwardTableId": [
      "ftb-uf6086r1hyecbxxxxxxxx"
    ]
  },
  "RequestId": "9037D769-24C8-46AD-83F3-4C0538FA5970",
  "SnatTableIds": {
    "SnatTableId": [
      "stb-uf6ppo11rsecmxxxxxxxx"
    ]
  }
}

---------------------------allocate_eip_address---------------------------
{
  "EipAddress": "101.xx.xx.110",
  "ResourceGroupId": "rg-acfmxazxxxxxxxx",
  "RequestId": "0DE621B4-6BDE-4E17-A294-8F71FBB9F710",
  "AllocationId": "eip-uf6d311cpmr0nxxxxxxxx"
}

---------------------------associate_eip_address eip---------------------------
{
  "RequestId": "C95B2EDC-F081-4784-B60B-2600F60E684D"
}

---------------------------create_snat_entry---------------------------
{
  "SnatEntryId": "snat-uf6ppbwshdu40xxxxxxxx",
  "RequestId": "BB9F8FD2-3CB5-4F84-8006-FE64BF3BEA06"
}

---------------------------describe_eip_address---------------------------
{
  "TotalCount": 1,
  "PageNumber": 1,
  "PageSize": 10,
  "EipAddresses": {
    "EipAddress": [
      {
        "ISP": "BGP",
        "ExpiredTime": "",
        "InternetChargeType": "PayByBandwidth",
        "IpAddress": "101.xx.xx.110",
        "AllocationId": "eip-uf6d311cpmr0nxxxxxxxx",
        "PrivateIpAddress": "",
        "Status": "InUse",
        "BandwidthPackageId": "",
        "InstanceId": "ngw-uf6l3c3rswubuxxxxxxxx",
        "InstanceRegionId": "cn-shanghai",
        "RegionId": "cn-shanghai",
        "AvailableRegions": {
          "AvailableRegion": [
            "cn-shanghai"
          ]
        },
        "ResourceGroupId": "rg-acfmxazxxxxxxxx",
        "HasReservationData": false,
        "InstanceType": "Nat",
        "AllocationTime": "2019-04-24T11:20:09Z",
        "Name": "",
        "OperationLocks": {
          "LockReason": []
        },
        "Mode": "NAT",
        "BandwidthPackageType": "",
        "BandwidthPackageBandwidth": "",
        "Bandwidth": "5",
        "HDMonitorStatus": "OFF",
        "ChargeType": "PostPaid",
        "SecondLimited": false,
        "Descritpion": ""
      }
    ]
  },
  "RequestId": "19052237-6E84-4258-89B9-05772C33C0DC"
}

---------------------------describe_nat_gateway---------------------------
{
  "TotalCount": 1,
  "PageNumber": 1,
  "RequestId": "26CAA3FE-B400-4522-9582-2DAAF69129AE",
  "PageSize": 10,
  "NatGateways": {
    "NatGateway": [
      {
        "Status": "Available",
        "BandwidthPackageIds": {
          "BandwidthPackageId": []
        },
        "VpcId": "vpc-uf6hxer3h07wgxxxxxxxx",
        "Description": "",
        "ForwardTableIds": {
          "ForwardTableId": [
            "ftb-uf6086r1hyecbxxxxxxxx"
          ]
        },
        "IpLists": {
          "IpList": [
            {
              "UsingStatus": "UsedBySnatTable",
              "IpAddress": "101.xx.xx.110",
              "AllocationId": "eip-uf6d311cpmr0nxxxxxxxx"
            }
          ]
        },
        "BusinessStatus": "Normal",
        "RegionId": "cn-shanghai",
        "CreationTime": "2019-04-24T11:20:06Z",
        "NatGatewayId": "ngw-uf6l3c3rswubuxxxxxxxx",
        "SnatTableIds": {
          "SnatTableId": [
            "stb-uf6ppo11rsecmxxxxxxxx"
          ]
        },
        "AutoPay": false,
        "InstanceChargeType": "PostPaid",
        "ExpiredTime": "",
        "Spec": "Small",
        "Name": ""
      }
    ]
  }
}

---------------------------delete_snat_entry---------------------------
{
  "RequestId": "CDA82881-ACF0-4DD1-887B-A764F56F180D"
}

---------------------------unassociate_eip_address nat--------------------------
-
{
  "RequestId": "140C46FF-0DB0-47F9-B0F4-3459DF117EAF"
}

---------------------------delete_nat_gateway---------------------------
{
  "RequestId": "8709747C-6786-443C-8AEA-51647AA49769"
}

---------------------------release_eip_address---------------------------
{
  "RequestId": "0BC21C23-0FB3-4594-8B14-6552DF788C93"
}

---------------------------delete_vswitch---------------------------
{
  "RequestId": "16E840EC-E058-40C1-A5BF-8CDF672EA139"
}

---------------------------delete_vpc---------------------------
{
  "RequestId": "B5F18126-FF2A-4005-9973-3984034DF0F4"
}