Object Storage Service:Manage symbolic links using OSS SDK for Node.js

Prerequisites

Before you begin, make sure that you have:

• An OSS bucket

• Environment variables OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET set with valid access credentials

• Read permissions on the symbolic link to query it

Create a symbolic link

The following example creates a symbolic link named symlinkobject.txt that points to exampleobject.txt.

const OSS = require('ali-oss');

const client = new OSS({
  // Bucket region. For example, oss-cn-hangzhou for China (Hangzhou).
  region: 'yourRegion',
  // Access credentials loaded from environment variables.
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  bucket: 'examplebucket',
});

// Optional headers. Uncomment the headers object and pass it as the third
// argument to putSymlink to apply storage class, ACL, or overwrite settings.
//
// const headers = {
//   'x-oss-storage-class': 'Standard',  // Storage class of the symbolic link object.
//   'x-oss-object-acl': 'private',      // Access control list (ACL) of the object.
//   'x-oss-forbid-overwrite': 'true',   // Set to 'true' to prevent overwriting an existing object with the same name.
// };

async function createSymlink() {
  try {
    const result = await client.putSymlink(
      'symlinkobject.txt',   // Name of the symbolic link to create.
      'exampleobject.txt'    // Name of the target object the symbolic link points to.
      // , { headers }       // Uncomment to apply optional headers defined above.
    );
    console.log(result);
  } catch (err) {
    console.error('Failed to create symbolic link:', err.name, err.message);
  }
}

createSymlink();

Query the object a symbolic link points to

Read permissions on the symbolic link are required to query it. The following example retrieves the target object name for symlinkobject.txt.

const OSS = require('ali-oss');

const client = new OSS({
  // Bucket region. For example, oss-cn-hangzhou for China (Hangzhou).
  region: 'yourRegion',
  // Access credentials loaded from environment variables.
  accessKeyId: process.env.OSS_ACCESS_KEY_ID,
  accessKeySecret: process.env.OSS_ACCESS_KEY_SECRET,
  authorizationV4: true,
  bucket: 'examplebucket',
});

// Query the target object name that the symbolic link points to.
client.getSymlink('symlinkobject.txt').then(r => console.log(r));

References

• PutSymlink — API operation for creating a symbolic link

• GetSymlink — API operation for querying a symbolic link