How to list objects using the Harmony SDK - Object Storage Service: Central de Documentação do Alibaba Cloud

Este tópico descreve como listar todos os objetos em um bucket usando o SDK do Object Storage Service (OSS) para Harmony.

Notas de uso

Para obter informações sobre as regiões e os endpoints compatíveis com o OSS, consulte Regions and endpoints.
Para listar objetos, é necessário ter a permissão oss:ListObjects. Para mais informações, consulte Attach a custom policy to a RAM user.

Código de exemplo

O código de exemplo a seguir mostra como chamar a operação ListObjectsV2 para listar objetos em um bucket:

import Client, { RequestError } from '@aliyun/oss';

// Create an OSSClient instance.
const client = new Client({
  // Specify the AccessKey ID obtained from Security Token Service (STS).
  accessKeyId: 'yourAccessKeyId',
  // Specify the AccessKey secret obtained from STS.
  accessKeySecret: 'yourAccessKeySecret',
  // Specify the security token obtained from STS.
  securityToken: 'yourSecurityToken',
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou.
  region: 'oss-cn-hangzhou',
});

/**
 * List objects in a bucket. 
 * Use the listObjectsV2 method to list objects in the bucket and the metadata of the objects. 
 */
const listObjectsV2 = async () => {
  try {
    // Use the listObjectsV2 method to list objects in the bucket and the metadata of the objects.
    const res = await client.listObjectsV2({
      bucket: 'yourBucketName', // Specify the name of the bucket.
    });

    // Display the objects and their metadata.
    console.log(JSON.stringify(res));
  } catch (err) {
    // Capture the exceptions during the request.
    if (err instanceof RequestError) {
      // If known types of errors exist, display information, such as the error code, error message, request ID, HTTP status code, and EC.
      console.log('code: ', err.code); // The error code.
      console.log('message: ', err.message); // The error message.
      console.log('requestId: ', err.requestId); // The request ID.
      console.log('status: ', err.status); // The HTTP status code.
      console.log('ec: ', err.ec); // The EC.
    } else {
      // Display other unknown types of errors.
      console.log('unknown error: ', err);
    }
  }
};

// Call the listObjectsV2 function to list objects in the bucket.
listObjectsV2();

Cenários comuns

Listar objetos com um prefixo específico

import Client, { RequestError } from '@aliyun/oss';

// Create an OSSClient instance.
const client = new Client({
  // Specify the AccessKey ID of the RAM user.
  accessKeyId: 'yourAccessKeyId',
  // Specify the AccessKey secret of the RAM user.
  accessKeySecret: 'yourAccessKeySecret',
  // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to oss-cn-hangzhou.
  region: 'oss-cn-hangzhou',
});

/**
 * List objects whose names contain a specific prefix in the bucket. 
 * Use the listObjectsV2 method and specify the prefix parameter to filter objects. 
 */
const listObjectsV2WithPrefix = async () => {
  try {
    // Use the listObjectsV2 method to list objects whose names contain a specific prefix in the bucket.
    const res = await client.listObjectsV2({
      bucket: 'yourBucketName', // Specify the name of the bucket.
      prefix: 'objectNamePrefix', // Specify the prefix contained in the names of the objects.
    });

    // Display the objects and their metadata.
    console.log(JSON.stringify(res));
  } catch (err) {
    // Capture exceptions during the request.
    if (err instanceof RequestError) {
      console.log('code: ', err.code); // The error code.
      console.log('message: ', err.message); // The error message.
      console.log('requestId: ', err.requestId); // The request ID.
      console.log('status: ', err.status); // The HTTP status code.
      console.log('ec: ', err.ec); // The EC.
    } else {
      console.log('unknown error: ', err);
    }
  }
};

// Call the listObjectsV2WithPrefix function to list objects whose names contain the specified prefix in the bucket.
listObjectsV2WithPrefix();

Listar objetos por delimitador

import Client, { RequestError } from '@aliyun/oss';

// Create an OSS client instance.
const client = new Client({
  // Replace this with the AccessKey ID of your RAM user.
  accessKeyId: 'yourAccessKeyId',
  // Replace this with the AccessKey secret of your RAM user.
  accessKeySecret: 'yourAccessKeySecret',
  // Specify the region where the bucket is located. For example, the region for China (Hangzhou) is 'oss-cn-hangzhou'.
  region: 'oss-cn-hangzhou',
});

/**
 * List objects in a bucket and use a separator.
 * Use the listObjectsV2 method and specify the delimiter parameter to simulate a folder structure.
 */
const listObjectsV2WithDelimiter = async () => {
  try {
    // Call the listObjectsV2 method to list objects in the specified bucket and use a separator to simulate a folder structure.
    const res = await client.listObjectsV2({
      bucket: 'yourBucketName', // The bucket name. Replace this with the name of the bucket that you use.
      delimiter: '/', // The separator. This is typically used to simulate a folder structure.
    });

    // Print the listed objects and their metadata.
    console.log(JSON.stringify(res));
  } catch (err) {
    // Catch exceptions that occur during the request.
    if (err instanceof RequestError) {
      console.log('code: ', err.code); // Error code
      console.log('message: ', err.message); // Error message
      console.log('requestId: ', err.requestId); // Request ID
      console.log('status: ', err.status); // HTTP status code
      console.log('ec: ', err.ec); // Error code
    } else {
      console.log('unknown error: ', err);
    }
  }
};

// Call the listObjectsV2WithDelimiter function to list objects using a separator.
listObjectsV2WithDelimiter();

Listar todos os objetos por página

import Client, { RequestError } from '@aliyun/oss';

// Create an OSS client instance.
const client = new Client({
  // Replace with the AccessKey ID of your RAM user.
  accessKeyId: 'yourAccessKeyId',
  // Replace with the AccessKey secret of your RAM user.
  accessKeySecret: 'yourAccessKeySecret',
  // Set the region where the bucket is located. For example, for a bucket in the China (Hangzhou) region, set the region to 'oss-cn-hangzhou'.
  region: 'oss-cn-hangzhou',
});

/**
 * List objects in a bucket page by page.
 * Use the listObjectsV2 method with the continuationToken parameter to list objects page by page.
 */
const listObjectsV2WithContinuationToken = async () => {
  try {
    let continuationToken: string | undefined; // The pagination token. It is initially empty.
    let isTruncated = true; // Indicates whether there are more objects to list.

    // Loop through and list objects until no more objects are left.
    while (isTruncated) {
      const res = await client.listObjectsV2({
        bucket: 'yourBucketName', // The bucket name. Replace with the name of your bucket.
        continuationToken, // The pagination token used to retrieve the next page of results.
      });

      // Print the objects on the current page and their metadata.
      console.log(JSON.stringify(res));

      // Update the pagination status.
      isTruncated = res.data.isTruncated; // Indicates whether there are more objects.
      continuationToken = res.data.nextContinuationToken; // The pagination token for the next page.
    }
  } catch (err) {
    // Catch exceptions that occur during the request.
    if (err instanceof RequestError) {
      console.log('code: ', err.code); // The error code.
      console.log('message: ', err.message); // The error message.
      console.log('requestId: ', err.requestId); // The request ID.
      console.log('status: ', err.status); // The HTTP status code.
      console.log('ec: ', err.ec); // The error code.
    } else {
      console.log('unknown error: ', err);
    }
  }
};

// Call the listObjectsV2WithContinuationToken function to list objects page by page.
listObjectsV2WithContinuationToken();

Listar objetos e obter informações do proprietário

import Client, { RequestError } from '@aliyun/oss';

// Create an OSS client instance.
const client = new Client({
  // Replace with the AccessKey ID of the RAM user.
  accessKeyId: 'yourAccessKeyId',
  // Replace with the AccessKey secret of the RAM user.
  accessKeySecret: 'yourAccessKeySecret',
  // Specify the region where the bucket is located. For example, the region for China (Hangzhou) is 'oss-cn-hangzhou'.
  region: 'oss-cn-hangzhou',
});

/**
 * Lists objects in a bucket and gets their owner information.
 * Use the listObjectsV2 method and set the fetchOwner parameter to get the owner information.
 */
const listObjectsV2WithFetchOwner = async () => {
  try {
    // Call the listObjectsV2 method to list objects in the specified bucket and get their owner information.
    const res = await client.listObjectsV2({
      bucket: 'yourBucketName', // The bucket name. Replace with the name of your bucket.
      fetchOwner: true, // Specifies whether to get the owner information of the objects.
    });

    // Print the listed objects and their metadata.
    console.log(JSON.stringify(res));
  } catch (err) {
    // Catch exceptions that occur during the request.
    if (err instanceof RequestError) {
      console.log('code: ', err.code); // Error code.
      console.log('message: ', err.message); // Error message.
      console.log('requestId: ', err.requestId); // Request ID.
      console.log('status: ', err.status); // HTTP status code.
      console.log('ec: ', err.ec); // Error code.
    } else {
      console.log('unknown error: ', err);
    }
  }
};

// Call the listObjectsV2WithFetchOwner function to list objects and get their owner information.
listObjectsV2WithFetchOwner();