Updated on 2025-09-22 GMT+08:00

Rewriting Response Headers

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.

When downloading an object, you can rewrite some HTTP/HTTPS response headers. The following table lists rewritable response headers.

Parameter

Description

ResponseContentType

Rewrites Content-Type in HTTP/HTTPS responses.

ResponseContentLanguage

Rewrites Content-Language in HTTP/HTTPS responses.

ResponseExpires

Rewrites Expires in HTTP/HTTPS responses.

ResponseCacheControl

Rewrites Cache-Control in HTTP/HTTPS responses.

ResponseContentDisposition

Rewrites Content-Disposition in HTTP/HTTPS responses.

NOTICE:

If you set SaveByType to file, rewriting Content-Disposition is not allowed. You need to use a temporary URL to download the file and rewrite Content-Disposition.

ResponseContentEncoding

Rewrites Content-Encoding in HTTP/HTTPS responses.

Rewriting the ContentType Response Header

The following code shows how to rewrite the ContentType response header:
// Create an instance of ObsClient.
var obsClient = new ObsClient({
    // Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK before storing them in the configuration file or environment variables. In this example, the AK and SK are stored in environment variables for identity authentication. Before running the code in 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'
});

obsClient.getObject({
       Bucket : 'bucketname',
       Key : 'objectname',
       ResponseContentType : 'image/jpeg'
}, 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 rewritten response headers.
                  console.log(result.InterfaceResult.ContentType);
              }
       }
});

Rewriting the ContentDisposition Response Header

The following code shows how to rewrite the ContentDisposition response header when SaveByType is set to file:
// Create an instance of ObsClient.
var obsClient = new ObsClient({
    // Hard-coded or plaintext AK and SK are risky. For security purposes, encrypt your AK and SK before storing them in the configuration file or environment variables. In this example, the AK and SK are stored in environment variables. Before running the code in 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 res = obsClient.createSignedUrlSync({
    Method: 'GET',
    Bucket: 'bucketName',
    Key: 'objectKey',
    Expires: 3600,
    QueryParams: {'response-content-disposition' : 'attachment; filename=name'}
});

console.log(res.SignedUrl)