刪除快照

下列 Java 程式碼範例列出閘道之每個磁碟區的快照，以及快照開始時間早於還是晚於指定的日期。它使用用於 Storage Gateway 和 Amazon EC2 的 Java API 的 AWS SDK。Amazon EC2 API 包含使用快照的操作。

更新程式碼以提供服務端點、閘道 Amazon Resource Name (ARN)，以及您要儲存快照的天數。會刪除此截止時間之前所建立的快照。您也需要指定布林值 viewOnly，指出要檢視要刪除的快照，還是實際執行快照刪除。首先，僅使用檢視選項來執行程式碼 (即，將 viewOnly 設定為 true)，以查看程式碼所刪除的內容。如需可與 Storage Gateway 搭配使用的 AWS 服務AWS Storage Gateway 端點清單，請參閱 AWS 一般參考.

import java.io.IOException;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.List;

import com.amazonaws.auth.PropertiesCredentials;
import com.amazonaws.services.ec2.AmazonEC2Client;
import com.amazonaws.services.ec2.model.DeleteSnapshotRequest;
import com.amazonaws.services.ec2.model.DescribeSnapshotsRequest;
import com.amazonaws.services.ec2.model.DescribeSnapshotsResult;
import com.amazonaws.services.ec2.model.Filter;
import com.amazonaws.services.ec2.model.Snapshot;
import com.amazonaws.services.storagegateway.AWSStorageGatewayClient;
import com.amazonaws.services.storagegateway.model.ListVolumesRequest;
import com.amazonaws.services.storagegateway.model.ListVolumesResult;
import com.amazonaws.services.storagegateway.model.VolumeInfo;

public class ListDeleteVolumeSnapshotsExample {

    public static AWSStorageGatewayClient sgClient;
    public static AmazonEC2Client ec2Client;    
    static String serviceURLSG = "https://storagegateway.us-east-1.amazonaws.com";
    static String serviceURLEC2 = "https://ec2.us-east-1.amazonaws.com"; 
    
    // The gatewayARN
    public static String gatewayARN = "*** provide gateway ARN ***";
    
    // The number of days back you want to save snapshots. Snapshots before this cutoff are deleted
    // if viewOnly = false.
    public static int daysBack = 10;
    
    // true = show what will be deleted; false = actually delete snapshots that meet the daysBack criteria
    public static boolean viewOnly = true;

    public static void main(String[] args) throws IOException {

        // Create a Storage Gateway and amazon ec2 client
        sgClient = new AWSStorageGatewayClient(new PropertiesCredentials(
                ListDeleteVolumeSnapshotsExample.class.getResourceAsStream("AwsCredentials.properties")));    
        sgClient.setEndpoint(serviceURLSG);
        
        ec2Client = new AmazonEC2Client(new PropertiesCredentials(
                ListDeleteVolumeSnapshotsExample.class.getResourceAsStream("AwsCredentials.properties")));
        ec2Client.setEndpoint(serviceURLEC2);        
        
        List<VolumeInfo> volumes = ListVolumesForGateway();
        DeleteSnapshotsForVolumes(volumes, daysBack);        
        
    }
    public static List<VolumeInfo> ListVolumesForGateway()
    {
        List<VolumeInfo> volumes = new ArrayList<VolumeInfo>();

        String marker = null;
        do {
            ListVolumesRequest request = new ListVolumesRequest().withGatewayARN(gatewayARN);
            ListVolumesResult result = sgClient.listVolumes(request);
            marker = result.getMarker();
            
            for (VolumeInfo vi : result.getVolumeInfos())
            {
                volumes.add(vi);
                System.out.println(OutputVolumeInfo(vi));
            }           
        } while (marker != null);

        return volumes;
    }
    private static void DeleteSnapshotsForVolumes(List<VolumeInfo> volumes,
            int daysBack2) {
        
        // Find snapshots and delete for each volume 
        for (VolumeInfo vi : volumes) {
            
            String volumeARN = vi.getVolumeARN();
            String volumeId = volumeARN.substring(volumeARN.lastIndexOf("/")+1).toLowerCase();
            Collection<Filter> filters = new ArrayList<Filter>();
            Filter filter = new Filter().withName("volume-id").withValues(volumeId);
            filters.add(filter);
            
            DescribeSnapshotsRequest describeSnapshotsRequest =
                new DescribeSnapshotsRequest().withFilters(filters);
            DescribeSnapshotsResult describeSnapshotsResult =
                ec2Client.describeSnapshots(describeSnapshotsRequest);
            
            List<Snapshot> snapshots = describeSnapshotsResult.getSnapshots();
            System.out.println("volume-id = " + volumeId);
            for (Snapshot s : snapshots){
                StringBuilder sb = new StringBuilder();
                boolean meetsCriteria = !CompareDates(daysBack, s.getStartTime());
                sb.append(s.getSnapshotId() + ", " + s.getStartTime().toString());                
                sb.append(", meets criteria for delete? " + meetsCriteria);
                sb.append(", deleted? ");
                if (!viewOnly & meetsCriteria) {
                    sb.append("yes");
                    DeleteSnapshotRequest deleteSnapshotRequest = 
                        new DeleteSnapshotRequest().withSnapshotId(s.getSnapshotId());
                    ec2Client.deleteSnapshot(deleteSnapshotRequest);
                }
                else {
                    sb.append("no");
                }
                System.out.println(sb.toString());                    
            }        
        }
    }

    private static String OutputVolumeInfo(VolumeInfo vi) {
        
        String volumeInfo = String.format(
                 "Volume Info:\n" + 
                 "  ARN: %s\n" +
                 "  Type: %s\n",
                 vi.getVolumeARN(),
                 vi.getVolumeType());
        return volumeInfo; 
     }
    
    // Returns the date in two formats as a list
    public static boolean CompareDates(int daysBack, Date snapshotDate) {
        Date today = new Date();
        Calendar cal = new GregorianCalendar();
        cal.setTime(today);
        cal.add(Calendar.DAY_OF_MONTH, -daysBack);
        Date cutoffDate = cal.getTime();        
        return (snapshotDate.compareTo(cutoffDate) > 0) ? true : false;
    }

}

在下列 C# 程式碼範例中， AWS Identity and Access Management 使用者可以列出閘道每個磁碟區的快照。使用者接著可以判斷快照開始時間早於還是晚於指定的日期 (保留期)，以及刪除已過保留期的快照。此範例使用適用於 Storage Gateway 和 Amazon EC2 的 .NET API AWS SDK。Amazon EC2 API 包含使用快照的操作。

下列程式碼範例會針對 .NET 版本 2 和 3 使用 AWS SDK。您可以將較舊版本的 .NET 遷移至較新版本。如需詳細資訊，請參閱將程式碼移轉至適用於 .NET 的最新版 AWS SDK。

更新程式碼以提供服務端點、閘道 Amazon Resource Name (ARN)，以及您要儲存快照的天數。會刪除此截止時間之前所建立的快照。您也需要指定布林值 viewOnly，指出要檢視要刪除的快照，還是實際執行快照刪除。首先，僅使用檢視選項來執行程式碼 (即，將 viewOnly 設定為 true)，以查看程式碼所刪除的內容。如需可與 Storage Gateway 搭配使用的 AWS 服務AWS Storage Gateway 端點清單，請參閱 AWS 一般參考.

首先，您建立使用者，並將最小 IAM 政策連接至使用者。然後，您排定閘道的自動化快照。

下列程式碼會建立允許使用者刪除快照的最小政策。在此範例中，政策命名為 sgw-delete-snapshot。

{
      "Version": "2012-10-17",
      "Statement": [
          {
              "Sid": "StmtEC2Snapshots",
              "Effect": "Allow",
              "Action": [
                  "ec2:DeleteSnapshot",
                  "ec2:DescribeSnapshots"
              ],
              "Resource": [
                  "*"
              ]
          },
          {
              "Sid": "StmtSgwListVolumes",
              "Effect": "Allow",
              "Action": [
                  "storagegateway:ListVolumes"
              ],
              "Resource": [
                  "*"
              ]
          }
      ]
  }

下列 C# 程式碼會找出指定閘道中符合磁碟區和指定截止期間的所有快照，然後予以刪除。

using System;
using System.Collections.Generic;
using System.Text;
using Amazon.EC2;
using Amazon.EC2.Model;
using Amazon.StorageGateway.Model;
using Amazon.StorageGateway;

namespace DeleteStorageGatewaySnapshotNS
{
    class Program
    {
        /*
         * Replace the variables below to match your environment.
         */
         
         /* IAM AccessKey */
        static String AwsAccessKey = "AKIA................";
        
        /* IAM SecretKey */
        static String AwsSecretKey = "*******************************";
        
        /* Account number, 12 digits, no hyphen */
        static String OwnerID = "123456789012";
        
        /* Your Gateway ARN. Use a Storage Gateway ID, sgw-XXXXXXXX* */ 
        static String GatewayARN = "arn:aws:storagegateway:ap-southeast-2:123456789012:gateway/sgw-XXXXXXXX";
        
        /* Snapshot status: "completed", "pending", "error" */                                                                                                      
        static String SnapshotStatus = "completed";
        
        /* Region where your gateway is activated */ 
        static String AwsRegion = "ap-southeast-2";
        
        /* Minimum age of snapshots before they are deleted (retention policy) */
        static int daysBack = 30; 

        /*
         * Do not modify the four lines below.
         */
        static AmazonEC2Config ec2Config;
        static AmazonEC2Client ec2Client;
        static AmazonStorageGatewayClient sgClient;
        static AmazonStorageGatewayConfig sgConfig;

        static void Main(string[] args)
        {
            // Create an EC2 client.
            ec2Config = new AmazonEC2Config();
            ec2Config.ServiceURL = "https://ec2." + AwsRegion + ".amazonaws.com";
            ec2Client = new AmazonEC2Client(AwsAccessKey, AwsSecretKey, ec2Config);

            // Create a Storage Gateway client.
            sgConfig = new AmazonStorageGatewayConfig();
            sgConfig.ServiceURL = "https://storagegateway." + AwsRegion + ".amazonaws.com";
            sgClient = new AmazonStorageGatewayClient(AwsAccessKey, AwsSecretKey, sgConfig);

            List<VolumeInfo> StorageGatewayVolumes = ListVolumesForGateway();
            List<Snapshot> StorageGatewaySnapshots = ListSnapshotsForVolumes(StorageGatewayVolumes, 
                                                     daysBack);
            DeleteSnapshots(StorageGatewaySnapshots);
        }

        /*
         * List all volumes for your gateway
         * returns: A list of VolumeInfos, or null.
         */
        private static List<VolumeInfo> ListVolumesForGateway()
        {
            ListVolumesResponse response = new ListVolumesResponse();
            try
            {
                ListVolumesRequest request = new ListVolumesRequest();
                request.GatewayARN = GatewayARN;
                response = sgClient.ListVolumes(request);

                foreach (VolumeInfo vi in response.VolumeInfos)
                {
                    Console.WriteLine(OutputVolumeInfo(vi));
                }
            }
            catch (AmazonStorageGatewayException ex)
            {
                Console.WriteLine(ex.Message);
            }
            return response.VolumeInfos;
        }

        /*
         * Gets the list of snapshots that match the requested volumes
         * and cutoff period.
         */
        private static List<Snapshot> ListSnapshotsForVolumes(List<VolumeInfo> volumes, int snapshotAge)
        {
            List<Snapshot> SelectedSnapshots = new List<Snapshot>();
            try
            {
                foreach (VolumeInfo vi in volumes)
                {
                    String volumeARN = vi.VolumeARN;
                    String volumeID = volumeARN.Substring(volumeARN.LastIndexOf("/") + 1).ToLower();

                    DescribeSnapshotsRequest describeSnapshotsRequest = new DescribeSnapshotsRequest();

                    Filter ownerFilter = new Filter();
                    List<String> ownerValues = new List<String>();
                    ownerValues.Add(OwnerID);
                    ownerFilter.Name = "owner-id";
                    ownerFilter.Values = ownerValues;
                    describeSnapshotsRequest.Filters.Add(ownerFilter);

                    Filter statusFilter = new Filter();
                    List<String> statusValues = new List<String>();
                    statusValues.Add(SnapshotStatus);
                    statusFilter.Name = "status";
                    statusFilter.Values = statusValues;
                    describeSnapshotsRequest.Filters.Add(statusFilter);

                    Filter volumeFilter = new Filter();
                    List<String> volumeValues = new List<String>();
                    volumeValues.Add(volumeID);
                    volumeFilter.Name = "volume-id";
                    volumeFilter.Values = volumeValues;
                    describeSnapshotsRequest.Filters.Add(volumeFilter);

                    DescribeSnapshotsResponse describeSnapshotsResponse = 
                      ec2Client.DescribeSnapshots(describeSnapshotsRequest);

                    List<Snapshot> snapshots = describeSnapshotsResponse.Snapshots;
                    Console.WriteLine("volume-id = " + volumeID);
                    foreach (Snapshot s in snapshots)
                    {
                        if (IsSnapshotPastRetentionPeriod(snapshotAge, s.StartTime))
                        {
                            Console.WriteLine(s.SnapshotId + ", " + s.VolumeId + ", 
                               " + s.StartTime + ", " + s.Description);
                            SelectedSnapshots.Add(s);
                        }
                    }
                }
            }
            catch (AmazonEC2Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            return SelectedSnapshots;
        }

        /*
         * Deletes a list of snapshots.
         */
        private static void DeleteSnapshots(List<Snapshot> snapshots)
        {
            try
            {
                foreach (Snapshot s in snapshots)
                {

                    DeleteSnapshotRequest deleteSnapshotRequest = new DeleteSnapshotRequest(s.SnapshotId);
                    DeleteSnapshotResponse response = ec2Client.DeleteSnapshot(deleteSnapshotRequest);
                    Console.WriteLine("Volume: " +
                              s.VolumeId +
                              " => Snapshot: " +
                              s.SnapshotId +
                              " Response: "
                              + response.HttpStatusCode.ToString());
                }
            }
            catch (AmazonEC2Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }

        /*
         * Checks if the snapshot creation date is past the retention period.
         */
        private static Boolean IsSnapshotPastRetentionPeriod(int daysBack, DateTime snapshotDate)
        {
            DateTime cutoffDate = DateTime.Now.Add(new TimeSpan(-daysBack, 0, 0, 0));
            return (DateTime.Compare(snapshotDate, cutoffDate) < 0) ? true : false;
        }

        /*
         * Displays information related to a volume.
         */
        private static String OutputVolumeInfo(VolumeInfo vi)
        {
            String volumeInfo = String.Format(
                "Volume Info:\n" +
                "  ARN: {0}\n" +
                "  Type: {1}\n",
                vi.VolumeARN,
                vi.VolumeType);
            return volumeInfo;
        }
    }
}

下列指 PowerShell 令碼範例會列出閘道每個磁碟區的快照，以及快照開始時間是在指定日期之前還是之後。它會使用 Storage Gateway 和 Amazon EC2 的 AWS Tools for Windows PowerShell 指令程式。Amazon EC2 API 包含使用快照的操作。

您需要更新指令碼，並提供閘道 Amazon Resource Name (ARN) 和您要儲存快照的天數。會刪除此截止時間之前所建立的快照。您也需要指定布林值 viewOnly，指出要檢視要刪除的快照，還是實際執行快照刪除。首先，僅使用檢視選項來執行程式碼 (即，將 viewOnly 設定為 true)，以查看程式碼所刪除的內容。

<#
.DESCRIPTION
    Delete snapshots of a specified volume that match given criteria.
    
.NOTES
    PREREQUISITES:
    1) AWS Tools for Windows PowerShell from https://aws.amazon.com/powershell/
    2) Credentials and AWS Region stored in session using Initialize-AWSDefault.
    For more info see, https://docs.aws.amazon.com/powershell/latest/userguide/specifying-your-aws-credentials.html 

.EXAMPLE
    powershell.exe .\SG_DeleteSnapshots.ps1  
#>

# Criteria to use to filter the results returned.
$daysBack = 18
$gatewayARN = "*** provide gateway ARN ***"
$viewOnly = $true;

#ListVolumes
$volumesResult = Get-SGVolume -GatewayARN $gatewayARN
$volumes = $volumesResult.VolumeInfos
Write-Output("`nVolume List")
foreach ($volumes in $volumesResult)
  { Write-Output("`nVolume Info:")
    Write-Output("ARN:  " + $volumes.VolumeARN)
    write-Output("Type: " + $volumes.VolumeType)
  }

Write-Output("`nWhich snapshots meet the criteria?")
foreach ($volume in $volumesResult)
  { 
    $volumeARN = $volume.VolumeARN
    
    $volumeId = ($volumeARN-split"/")[3].ToLower()
  
    $filter = New-Object Amazon.EC2.Model.Filter
    $filter.Name = "volume-id"
    $filter.Value.Add($volumeId)
    
    $snapshots = get-EC2Snapshot -Filter $filter    
    Write-Output("`nFor volume-id = " + $volumeId)
    foreach ($s in $snapshots)
    {
       $d = ([DateTime]::Now).AddDays(-$daysBack)
       $meetsCriteria = $false
       if ([DateTime]::Compare($d, $s.StartTime) -gt 0)
       {
            $meetsCriteria = $true
       }
       
       $sb = $s.SnapshotId + ", " + $s.StartTime + ", meets criteria for delete? " + $meetsCriteria
       if (!$viewOnly -AND $meetsCriteria) 
       {
           $resp = Remove-EC2Snapshot -SnapshotId $s.SnapshotId
           #Can get RequestId from response for troubleshooting.
           $sb = $sb + ", deleted? yes"
       }
       else {
           $sb = $sb + ", deleted? no"
       }
       Write-Output($sb) 
    }
  }