使用開發套件執行 Amazon S3 物件的多部分複本 AWS - AWS SDK 程式碼範例

AWS 文件 AWS SDK 範例 GitHub 存放庫中提供了更多 SDK 範例。

本文為英文版的機器翻譯版本，如內容有任何歧義或不一致之處，概以英文版為準。

使用開發套件執行 Amazon S3 物件的多部分複本 AWS

下列程式碼範例示範如何執行 Amazon S3 物件的分段複製。

.NET
AWS SDK for .NET
注意

還有更多關於 GitHub。尋找完整範例，並了解如何在AWS 設定和執行程式碼範例儲存庫。

    using System;
    using System.Collections.Generic;
    using System.Threading.Tasks;
    using Amazon.S3;
    using Amazon.S3.Model;

    /// <summary>
    /// This example shows how to perform a multi-part copy from one Amazon
    /// Simple Storage Service (Amazon S3) bucket to another.
    /// </summary>
    public class MPUapiCopyObj
    {
        private const string SourceBucket = "doc-example-bucket1";
        private const string TargetBucket = "doc-example-bucket2";
        private const string SourceObjectKey = "example.mov";
        private const string TargetObjectKey = "copied_video_file.mov";

        /// <summary>
        /// This method starts the multi-part upload.
        /// </summary>
        public static async Task Main()
        {
            var s3Client = new AmazonS3Client();
            Console.WriteLine("Copying object...");
            await MPUCopyObjectAsync(s3Client);
        }

        /// <summary>
        /// This method uses the passed client object to perform a multipart
        /// copy operation.
        /// </summary>
        /// <param name="client">An Amazon S3 client object that will be used
        /// to perform the copy.</param>
        public static async Task MPUCopyObjectAsync(AmazonS3Client client)
        {
            // Create a list to store the copy part responses.
            var copyResponses = new List<CopyPartResponse>();

            // Setup information required to initiate the multipart upload.
            var initiateRequest = new InitiateMultipartUploadRequest
            {
                BucketName = TargetBucket,
                Key = TargetObjectKey,
            };

            // Initiate the upload.
            InitiateMultipartUploadResponse initResponse =
                await client.InitiateMultipartUploadAsync(initiateRequest);

            // Save the upload ID.
            string uploadId = initResponse.UploadId;

            try
            {
                // Get the size of the object.
                var metadataRequest = new GetObjectMetadataRequest
                {
                    BucketName = SourceBucket,
                    Key = SourceObjectKey,
                };

                GetObjectMetadataResponse metadataResponse =
                    await client.GetObjectMetadataAsync(metadataRequest);
                var objectSize = metadataResponse.ContentLength; // Length in bytes.

                // Copy the parts.
                var partSize = 5 * (long)Math.Pow(2, 20); // Part size is 5 MB.

                long bytePosition = 0;
                for (int i = 1; bytePosition < objectSize; i++)
                {
                    var copyRequest = new CopyPartRequest
                    {
                        DestinationBucket = TargetBucket,
                        DestinationKey = TargetObjectKey,
                        SourceBucket = SourceBucket,
                        SourceKey = SourceObjectKey,
                        UploadId = uploadId,
                        FirstByte = bytePosition,
                        LastByte = bytePosition + partSize - 1 >= objectSize ? objectSize - 1 : bytePosition + partSize - 1,
                        PartNumber = i,
                    };

                    copyResponses.Add(await client.CopyPartAsync(copyRequest));

                    bytePosition += partSize;
                }

                // Set up to complete the copy.
                var completeRequest = new CompleteMultipartUploadRequest
                {
                    BucketName = TargetBucket,
                    Key = TargetObjectKey,
                    UploadId = initResponse.UploadId,
                };
                completeRequest.AddPartETags(copyResponses);

                // Complete the copy.
                CompleteMultipartUploadResponse completeUploadResponse =
                    await client.CompleteMultipartUploadAsync(completeRequest);
            }
            catch (AmazonS3Exception e)
            {
                Console.WriteLine($"Error encountered on server. Message:'{e.Message}' when writing an object");
            }
            catch (Exception e)
            {
                Console.WriteLine($"Unknown encountered on server. Message:'{e.Message}' when writing an object");
            }
        }
    }