Initialization - Object Storage Service - Alibaba Cloud Documentation Center

OssClient serves as the OSS .NET client to manage OSS resources such as buckets and objects.

Create an OssClient instance

Note To create an OssClient instance, you must specify an endpoint. For more information about endpoints, see Regions and endpoints.

You can use one of the following methods to create an OssClient instance:

Use an endpoint to create an OssClient instance

The following code provides an example on how to create an OssClient instance based on an OSS endpoint:

using Aliyun.OSS;
// The AccessKey pair of an Alibaba Cloud account has permissions on all API operations. Using these credentials to perform operations in OSS is a high-risk operation. We recommend that you use a RAM user to call API operations or perform routine O&M. To create a RAM user, log on to the RAM console. 
const string accessKeyId = "yourAccessKeyId";
const string accessKeySecret = "yourAccessKeySecret";
// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
const string endpoint = "https://oss-cn-hangzhou.aliyuncs.com";

// Create an OssClient instance. 
var ossClient = new OssClient(endpoint, accessKeyId, accessKeySecret);

Use a custom domain name to create an OssClient instance

The following code provides an example on how to create an OssClient instance by using a custom domain name:

Important ossClient.listBuckets is unavailable if a custom domain name is used.

using Aliyun.OSS;
using Aliyun.OSS.Common;
// The AccessKey pair of an Alibaba Cloud account has permissions on all API operations. Using these credentials to perform operations in OSS is a high-risk operation. We recommend that you use a RAM user to call API operations or perform routine O&M. To create a RAM user, log on to the RAM console. 
const string accessKeyId = "yourAccessKeyId";
const string accessKeySecret = "yourAccessKeySecret";
// Specify the custom domain name. 
const string endpoint = "yourDomain";

// Create a ClientConfiguration instance. Modify parameters as required. 
var conf = new ClientConfiguration();

// Specify that a CNAME can be used as an endpoint to create the OssClient instance. A CNAME record specifies the mapping relationship between a custom domain name and a bucket. 
conf.IsCname = true;

// Create an OSSClient instance. 
var client = new OssClient(endpoint, accessKeyId, accessKeySecret, conf);

Use STS to create an OssClient instance

The following code provides an example on how to create an OssClient instance based on Security Token Service (STS):

using Aliyun.OSS;
// Specify the temporary AccessKey pair obtained from STS. 
const string accessKeyId = "yourAccessKeyId";
const string accessKeySecret = "yourAccessKeySecret";
// Specify the security token obtained from STS. 
const string  securityToken = "yourSecurityToken";
// Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
const string endpoint = "https://oss-cn-hangzhou.aliyuncs.com";

// Create an OssClient instance. 
var ossClient = new OssClient(endpoint, accessKeyId, accessKeySecret, securityToken);

Configure an OssClient instance

ClientConfiguration is a configuration class of OssClient. You can use ClientConfiguration to configure parameters such as host proxies, connection timeouts, and the maximum number of connections. You can configure the following parameters.


Parameter	Description	Default value
ConnectionLimit	The maximum number of concurrent connections.	512
MaxErrorRetry	The maximum number of retry attempts in the case of a request error.	3
ConnectionTimeout	The timeout period for connections. Unit: milliseconds.	-1 (no timeout)
EnalbeMD5Check	Specifies whether to enable MD5 verification when you upload or download objects. true false Important The system performance may be compromised if MD5 verification is enabled.	false
IsCname	Specifies whether a CNAME can be used as an endpoint to create the OssClient instance. CNAME is used to bind a custom domain name to a bucket.	false
ProgressUpdateInterval	The update interval of the progress bar. Unit: bytes.	8096
ProxyHost	The address of the proxy server. Example: `example.aliyundoc.com`.	None
ProxyPort	The port of the proxy server. Example: `3128` or `8080`.	None
ProxyUserName	The account used to log on to the proxy server. This parameter is optional.	None
ProxyPassword	The password used to log on to the proxy server. This parameter is optional.	None

The following code provides an example on how to configure an OssClient instance:

using Aliyun.OSS;
using Aliyun.OSS.Common;

var conf = new ClientConfiguration();
// Specify the maximum number of concurrent connections. 
ClientConfiguration.ConnectionLimit = 512;
// Specify the maximum number of retry attempts in the case of a request error. 
conf.MaxErrorRetry = 3;
// Specify the timeout period for connections. 
conf.ConnectionTimeout = 300;
// Enable MD5 verification. 
conf.EnalbeMD5Check = true;
// Specify the proxy server. 
conf.ProxyHost = "example.aliyundoc.com";
// Specify the port of the proxy server. 
conf.ProxyPort = 3128;
// Specify the username used to access the proxy network. 
conf.ProxyUserName = "user";
// Specify the password used to access the proxy network. 
conf.ProxyPassword = "password";

var client = new OssClient(endpoint, accessKeyId, accessKeySecret, conf);