Help Center> Object Storage Service> BrowserJS> Object Upload> Performing a Multipart Copy
Updated on 2024-04-26 GMT+08:00

Performing a Multipart Copy

If you have any questions during development, post them on the Issues page of GitHub. For details about parameters and usage of each API, see the API Reference.

As a special case of multipart upload, multipart copy implements multipart upload by copying the whole or partial object in a bucket. You can call ObsClient.copyPart to copy parts. 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. For details, see https://support.huaweicloud.com/intl/en-us/usermanual-ca/ca_01_0003.html.
    access_key_id: process.env.AccessKeyID,
    secret_access_key: process.env.SecretAccessKey,
    // Replace the example endpoint with the actual one in your case.
    server: 'https://obs.ap-southeast-1.myhuaweicloud.com'
});

var destBucketName = 'destbucketname';
var destObjectKey = 'destobjectname';
var sourceBucketName = 'sourcebucketname';
var sourceObjectKey = 'sourceobjectname';

obsClient.CopyPart({
       Bucket : destBucketName,
       Key : destObjectKey,
       // Set the part number, which ranges from 1 to 10000.
       PartNumber : 1,
       // Set the upload ID.
       UploadId : 'upload id from initiateMultipartUpload',
       // Set the source object to be copied.
       CopySource : sourceBucketName + '/' + sourceObjectKey,
       // Set the to-be-copied range of the source object.
       CopySourceRange : 'bytes=0-100'
}, function(err, result) {
       if (err) {
              console.log('Error-->' + err);
       } else {
              console.log('Status-->' + result.CommonMsg.Status);
              if (result.CommonMsg.Status < 300 && result.InterfaceResult) {
                     console.log('RequestId-->' + result.InterfaceResult.RequestId);
                     console.log('LastModified-->' + result.InterfaceResult.LastModified);
                     console.log('ETag-->' + result.InterfaceResult.ETag);
              }
       }
});

Use the PartNumber parameter to specify the part number, the UploadId parameter to specify the globally unique ID for the multipart upload, the CopySource parameter to specify the information about the source object, and the CopySourceRange parameter to specify the copy range.