Updated on 2026-01-16 GMT+08:00

Downloading a Cold Object

Before you can download a Cold object, you must restore it. Cold objects can be restored in either of the following ways.

Option

Description

Value in OBS BrowserJS SDK

Expedited restore

Data can be restored within 1 to 5 minutes.

ObsClient.enums.RestoreTierExpedited

Standard restore

Data can be restored within 3 to 5 hours. This is the default option.

ObsClient.enums.RestoreTierStandard

To prolong the validity period of the Cold data restored, you can repeatedly restore the data, but you will be billed for each restoration. After a second restore, the validity period of Standard object copies will be prolonged, and you need to pay for storing these copies during the prolonged period.

You can call ObsClient.restoreObject to restore a Cold object. Sample code is as follows:

// Create an instance of ObsClient.
var obsClient = new ObsClient({
    // Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables AccessKeyID and SecretAccessKey.
    // The front-end code does not have the process environment variable, so you need to use a module bundler like webpack to define the process variable.
    // Obtain an AK/SK pair on the management console.
    access_key_id: process.env.AccessKeyID,
    secret_access_key: process.env.SecretAccessKey,
    server: 'https://your-endpoint'
});

// Restore an object in the Cold storage class.
obsClient.restoreObject({
       Bucket : 'bucketname',
       Key : 'objectname',
       Days : 1,
       Tier : obsClient.enums.RestoreTierExpedited
}, function (err, result) {
       if(err){
              console.error('Error-->' + err);
       }else{
              console.log('Status-->' + result.CommonMsg.Status);
              
// Wait for the object to be restored.
              setTimeout(function () {
                     
                     // Download the object and obtain the object content.
                     obsClient.getObject({
                           Bucket : 'bucketname',
                           Key : 'objectname'
                     }, function (err, result) {
                            if(err){              
                               console.error('Error-->' + err);       
                            }else{              
                               console.log('Status-->' + result.CommonMsg.Status); 
                               if(result.CommonMsg.Status < 300 && result.InterfaceResult){     
                                   // Obtain the object content.
                                   console.log('Object Content:');                            
                                   console.log(result.InterfaceResult.Content);   
                               }    
                            }
                     });
              }, 6 * 60 * 1000);
       }
});
  • The object specified in ObsClient.restoreObject must be in the OBS Cold storage class. Otherwise, an error will be reported when you call this API.
  • Use the Days parameter to specify the retention period (from 1 to 30 days) of the restored objects and the Tier parameter to specify the time spent on restoring the objects.