Torch Object Storage
Torch Object Storage
Torch Object Storage
Document
What's New
Announcements
Billing
Billable items
Billing method
Getting Started
User Guide
Working with buckets
Basic configurations
Managing lifecycle
Back-to-origin rules
Event notification
Intelligent Tiering
Permissions
Domain management
Fault tolerance and disaster recovery
Cross-region replication
Same-region replication
Data redundancy
Image processing
ObjectSet
Working with objects
Managing folders
Monitoring and alerting
Metric monitoring
Access control
Bucket policies
Common configuration scenarios
Authorizing IAM users of the current account
Authorizing other accounts
Managing access via tools and SDKs
Managing public read access
Data security
Access points
Multi-region access points (MRAP)
Single-region access points (SRAP)
Converged access points (CAP)
DevMind
TOS accelerator
SenseFlow
TOS Agent
Data processing
Basic concepts
Image processing
Media processing
Document preview
Task processing
Data subscription
Flow control management
Quality of Service (QoS) policies
Hierarchical namespace (HNS)
User guide
Tool reference
Best practices
TOS Vectors
User guide
API reference
Vector bucket
Vector index
SDK reference
Python-Vectors
Vector bucket
Vector index
Java-Vectors
Vector bucket
Vector index
Node.js-Vectors
Vector bucket
Vector index
Tool Guide
tosutil
Common commands
Upload, download, and copy objects
Share objects
Auxiliary commands
Common examples
TOS Browser
FSX
FSX best practices
TOS PyTorch Connector
tosfsspec
API Reference
Signature Mechanism
The header contains a signature
Bucket
Basic Bucket Operations
Bucket Lifecycle
Access Monitor
Bucket ACL
Bucket CORS
Bucket Policy
Back-to-origin Rules
Bucket Replication
Versioning
Static Website
Event Notification
Custom Domain
Server-side encryption
Transfer Acceleration
Data Processing
Image processing
Media processing
Video transcoding
Audio transcoding
video to GIF
Document preview
File decompression
Log Storage
Retention Policy
Requester pays
TLS version
Object
Basic Object Operations
Object ACL
Fetch Object
Symbolic Link
WORM object
Multipart Upload
SDK Reference
Java
Pre-signing Mechanism
Bucket Interface
Basic Bucket Interface
Manage Bucket Configuration
Object Interface
Upload Object
Download Object
Upload and Download Speed Limit
Copy Object
List Object
Data Processing
Image Processing
Video Processing
Audio Processing
Log Configuration
Hierarchical Namespace
Bucket base interface
Introduction to Typical Scenes
Python
Data processing
Pre-signature mechanism
Bucket interface
Basic bucket interface
Manage bucket configuration
Object interface
Upload object
Download object
Copy object
List objects
Introduction to typical scenes
C
Object Interface
Upload object
C++
Pre-signature Mechanism
Bucket Interface
Basic Bucket Interface
Manage Bucket Configuration
Object Interface
Upload Object
Download Object
Copy Object
List Objects
Data Processing
Go
Object Interface
Upload Object
Download Object
Copy Object
List Objects
Manage Objects
Bucket Interface
Manage Bucket Configuration
Data Processing
Log Configuration
Introduction to Typical Scenes
Pre-signature Mechanism
Node.js
Pre-signature Mechanism
Bucket Interface
Basic Bucket Interface
Manage Bucket Configuration
Object Interface
Upload object
Download object
Copy object
List objects
Data Processing
Image Processing
Introduction to Typical Scenes
Browser.js
Pre-signature Mechanism
Upload Object
Download Object
Copy Object
List Objects
Manage Objects
Data Processing
.NET
Bucket Interface
Object Interface
Upload Object
Download Object
List Objects
Introduction to Typical Scenes
PHP
Bucket Interface
Object Interface
Download Object
Data Processing
Exception Handling
Android
Bucket Interface
Object Interface
Upload Object
Download Object
Exception Handling
iOS
Bucket Interface
Object Interface
Upload Object
Download Object
Harmony
Pre-signature Mechanism
Bucket Interface
Object Interface
Upload Object
Download Object
List Objects v2
Introduction to Typical Scenarios
Rust
Pre-signing mechanism
Bucket interface
Basic bucket operations
Lifecycle rules
Bucket ACLs
Cross-origin resource sharing
Bucket inventory
Back-to-origin rules
Bucket replication
Static website hosting
Event notification
Custom domain
Server-side encryption
Object interface
Basic operation
Access control
Error Codes
01-SERVICE_ERROR
02-AUTH
03-ACCESS_CONTROL
04-QOS
05-REQUEST
06-BUCKET
07-LIFECYCLE
08-ACL
09-CORS
10-POLICY
11-MIRROR
12-REPLICATION
13-WEBSITE
14-NOTIFICATION
15-ENCRYPT
16-CUSTOMDOMAIN
17-OBJECT
18-TAG
19-MULTIPART
20-STORAGE_CLASS
21-CALLBACK
22-DATA_PROCESS
23-BATCH
24-STORAGE_LENS
25-INVENTORY
26-DIRECTORY_BUCKET
FAQ
Best Practices
AIGC-Doubao LLMs
Accessing TOS with third-party tools
Granting temporary access
Data migration
Data processing
Checking data integrity
Performance optimization
- Documentation
Torch Object StorageSDK Reference.NETObject InterfaceUpload ObjectMultipart Upload (.NET SDK)
Copy page
Download PDFUpload Object
Multipart Upload (.NET SDK)
Copy pageDownload PDFMultipart Upload (.NET SDK)
If you need to upload large objects, it is recommended to divide them into multiple data blocks (parts) and upload each separately. Finally, invoke the merge parts operation to combine the uploaded data blocks into a single object.
Notes
- Before initiating multipart upload, you must ensure that your account has the tos:PutObject permission. For detailed instructions, please refer to the Permission Configuration Guide.
- To cancel a multipart upload task, you must have the tos:AbortMultipartUpload permission. For detailed instructions, please refer to the Permission Configuration Guide.
- When uploading an object, the object name must comply with the naming conventions. For more information, please refer to Object Naming Conventions.
- TOS is a distributed object storage product designed for massive data storage. Its internal partitions store object index data. To horizontally scale the maximum throughput for uploading and downloading objects, and to reduce the probability of partitions becoming hotspots, please avoid using lexicographically incremental object naming. For more information, see Performance Optimization.
- If an object with the same name already exists in the bucket, the new object will overwrite the existing one. When bucket versioning is enabled, the original object is retained, and a new version number is generated to identify the newly uploaded object.
Multipart Upload Procedure
Multipart upload using the TOS .NET SDK consists of the following three steps.
- Initialize Multipart Upload Task
- Invoking the createMultipartUpload interface returns a globally unique uploadId created by TOS.
- Upload Chunk
- Call the uploadPart interface to upload data chunks.
tip
- For the same multipart upload task (identified by uploadId), the part number (partNumber) indicates the relative position of the part within the entire object. If data is uploaded multiple times using the same shard number, TOS will overwrite the existing data, and only the data from the most recent upload will be retained.
- The uploadPart API returns the MD5 value of the part data, which can be obtained through the ETag field. When merging parts, you must specify the information for all uploaded parts in the current multipart upload task, including the part number and ETag value.
- Complete Multipart Upload
- After all parts have been uploaded, call the completeMultipartUpload API to merge all parts into a complete object.
Sample Code
Complete Process of Multipart Upload
The following code demonstrates the complete process of uploading a local file using multipart upload, while specifying the ACL as Private, setting the storage type to Infrequent Access Storage, and adding custom metadata during the upload.
using System;
using System.Collections.Generic;
using System.IO;
using TOS;
using TOS.Error;
using TOS.Model;
namespace ConsoleApp
{
internal class Program
{
private static void Main(string[] args)
{
var ak = Environment.GetEnvironmentVariable("TOS_ACCESS_KEY");
var sk = Environment.GetEnvironmentVariable("TOS_SECRET_KEY");
var endpoint = "https://tos-cn-beijing.volces.com";
var region = "cn-beijing";
var bucketName = "*** Provide your bucket name ***";
var objectKey = "example_dir/example.txt";
var localFileName = "/usr/local/test.txt";
var client = TosClientBuilder.Builder().SetAk(ak).SetSk(sk).SetEndpoint(endpoint).SetRegion(region).Build();
var uploadID = "";
try
{
var createMultipartUploadInput = new CreateMultipartUploadInput
{
Bucket = bucketName,
Key = objectKey,
ACL = ACLType.ACLPrivate,
StorageClass = StorageClassType.StorageClassIa,
Meta = new Dictionary<string, string> { { "key", "value" } }
};
var createMultipartUploadOutput = client.CreateMultipartUpload(createMultipartUploadInput);
uploadID = createMultipartUploadOutput.UploadID;
Console.WriteLine("CreateMultipartUpload succeeded, request id {0}",
createMultipartUploadOutput.RequestID);
Console.WriteLine("CreateMultipartUpload succeeded, upload id {0}", uploadID);
}
catch (TosServerException ex)
{
Console.WriteLine("CreateMultipartUpload failed, request id {0}", ex.RequestID);
Console.WriteLine("CreateMultipartUpload failed, status code {0}", ex.StatusCode);
Console.WriteLine("CreateMultipartUpload failed, response error code {0}", ex.Code);
Console.WriteLine("CreateMultipartUpload failed, response error message {0}", ex.Message);
}
catch (TosClientException ex)
{
Console.WriteLine("CreateMultipartUpload failed, error message {0}", ex.Message);
}
catch (Exception ex)
{
Console.WriteLine("CreateMultipartUpload failed, {0}", ex.Message);
}
long partSize = 20 * 1024 * 1024;
var fi = new FileInfo(localFileName);
var fileSize = fi.Length;
var partCount = fileSize / partSize;
if (fileSize % partSize != 0) partCount++;
var parts = new UploadedPart[partCount];
try
{
using (var fileStream = File.Open(localFileName, FileMode.Open, FileAccess.Read))
{
for (var i = 0; i < partCount; i++)
{
var offset = partSize * i;
fileStream.Seek(offset, 0);
var contentSize = partSize < fileSize - offset ? partSize : fileSize - offset;
var UploadPartInput = new UploadPartInput
{
Bucket = bucketName,
Key = objectKey,
UploadID = uploadID,
PartNumber = i + 1,
Content = fileStream,
ContentLength = contentSize
};
var uploadPartOutput = client.UploadPart(UploadPartInput);
parts[i] = new UploadedPart { PartNumber = i + 1, ETag = uploadPartOutput.ETag };
Console.WriteLine("UploadPart succeeded, request id {0}", uploadPartOutput.RequestID);
}
}
}
catch (TosServerException ex)
{
Console.WriteLine("UploadPart failed, request id {0}", ex.RequestID);
Console.WriteLine("UploadPart failed, status code {0}", ex.StatusCode);
Console.WriteLine("UploadPart failed, response error code {0}", ex.Code);
Console.WriteLine("UploadPart failed, response error message {0}", ex.Message);
}
catch (TosClientException ex)
{
Console.WriteLine("UploadPart failed, error message {0}", ex.Message);
}
catch (Exception ex)
{
Console.WriteLine("UploadPart failed, {0}", ex.Message);
}
try
{
var completeMultipartUploadInput = new CompleteMultipartUploadInput
{
Bucket = bucketName,
Key = objectKey,
UploadID = uploadID,
Parts = parts
};
var completeMultipartUploadOutput = client.CompleteMultipartUpload(completeMultipartUploadInput);
Console.WriteLine("CompleteMultipartUpload succeeded, request id {0}",
completeMultipartUploadOutput.RequestID);
}
catch (TosServerException ex)
{
Console.WriteLine("CompleteMultipartUpload failed, request id {0}", ex.RequestID);
Console.WriteLine("CompleteMultipartUpload failed, status code {0}", ex.StatusCode);
Console.WriteLine("CompleteMultipartUpload failed, response error code {0}", ex.Code);
Console.WriteLine("CompleteMultipartUpload failed, response error message {0}", ex.Message);
}
catch (TosClientException ex)
{
Console.WriteLine("CompleteMultipartUpload failed, error message {0}", ex.Message);
}
catch (Exception ex)
{
Console.WriteLine("CompleteMultipartUpload failed, {0}", ex.Message);
}
}
}
}
List Uploaded Parts
The following code is used to list the information about uploaded parts of a specified object within a storage bucket.
using System;
using TOS;
using TOS.Error;
using TOS.Model;
namespace ConsoleApp
{
internal class Program
{
private static void Main(string[] args)
{
var ak = Environment.GetEnvironmentVariable("TOS_ACCESS_KEY");
var sk = Environment.GetEnvironmentVariable("TOS_SECRET_KEY");
var endpoint = "https://tos-cn-beijing.volces.com";
var region = "cn-beijing";
var bucketName = "*** Provide your bucket name ***";
var objectKey = "*** Provide your object key ***";
var uploadID = "*** Provide upload ID ***";
var client = TosClientBuilder.Builder().SetAk(ak).SetSk(sk).SetEndpoint(endpoint).SetRegion(region).Build();
try
{
var truncated = true;
var marker = 0;
while (truncated)
{
var createMultipartUploadInput = new ListPartsInput
{
Bucket = bucketName,
Key = objectKey,
UploadID = uploadID,
PartNumberMarker = marker
};
var listPartsOutput = client.ListParts(createMultipartUploadInput);
truncated = listPartsOutput.IsTruncated;
marker = listPartsOutput.NextPartNumberMarker;
Console.WriteLine("ListParts succeeded, request id {0}", listPartsOutput.RequestID);
Console.WriteLine("ListParts succeeded, upload id {0}", uploadID);
foreach (var part in listPartsOutput.Parts)
{
Console.WriteLine("ListParts succeeded, part number {0}", part.PartNumber);
Console.WriteLine("ListParts succeeded, part Etag {0}", part.ETag);
Console.WriteLine("ListParts succeeded, part size {0}", part.Size);
}
}
}
catch (TosServerException ex)
{
Console.WriteLine("ListParts failed, request id {0}", ex.RequestID);
Console.WriteLine("ListParts failed, status code {0}", ex.StatusCode);
Console.WriteLine("ListParts failed, response error code {0}", ex.Code);
Console.WriteLine("ListParts failed, response error message {0}", ex.Message);
}
catch (TosClientException ex)
{
Console.WriteLine("ListParts failed, error message {0}", ex.Message);
}
catch (Exception ex)
{
Console.WriteLine("ListParts failed, {0}", ex.Message);
}
}
}
}
Cancel Multipart Upload Task
You can cancel a multipart upload task using the AbortMultipartUpload API. After a multipart upload task is canceled, TOS will delete the already uploaded part data. You will no longer be able to perform any operations on this multipart upload task.
The following code is used to cancel a multipart upload task.
using System;
using TOS;
using TOS.Error;
using TOS.Model;
namespace ConsoleApp
{
internal class Program
{
private static void Main(string[] args)
{
var ak = Environment.GetEnvironmentVariable("TOS_ACCESS_KEY");
var sk = Environment.GetEnvironmentVariable("TOS_SECRET_KEY");
var endpoint = "https://tos-cn-beijing.volces.com";
var region = "cn-beijing";
var bucketName = "*** Provide your bucket name ***";
var objectKey = "*** Provide your object key ***";
var uploadID = "*** Provide upload ID ***";
var client = TosClientBuilder.Builder().SetAk(ak).SetSk(sk).SetEndpoint(endpoint).SetRegion(region).Build();
try
{
var abortMultipartUploadInput = new AbortMultipartUploadInput()
{
Bucket = bucketName,
Key = objectKey,
UploadID = uploadID,
};
var abortMultipartUploadOutput = client.AbortMultipartUpload(abortMultipartUploadInput);
Console.WriteLine("AbortMultipartUpload succeeded, request id {0}", abortMultipartUploadOutput.RequestID);
}
catch (TosServerException ex)
{
Console.WriteLine("AbortMultipartUpload failed, request id {0}", ex.RequestID);
Console.WriteLine("AbortMultipartUpload failed, status code {0}", ex.StatusCode);
Console.WriteLine("AbortMultipartUpload failed, response error code {0}", ex.Code);
Console.WriteLine("AbortMultipartUpload failed, response error message {0}", ex.Message);
}
catch (TosClientException ex)
{
Console.WriteLine("AbortMultipartUpload failed, error message {0}", ex.Message);
}
catch (Exception ex)
{
Console.WriteLine("AbortMultipartUpload failed, {0}", ex.Message);
}
}
}
}
Related documentation
- For a detailed introduction to the API interface for creating multipart upload tasks, see CreateMultipartUpload.
- For a detailed introduction to the UploadPart API, please refer to UploadPart.
- For a detailed introduction to the API for merging parts, see CompleteMultipartUpload.
- For a detailed introduction to the API interface for aborting multipart upload tasks, please refer to AbortMultipartUpload.
Last updated: 2025.09.23 11:28:05
All rights reserved © Beijing Volcano Engine Technology Co., Ltd2024
