上传回调是指客户端在请求时携带回调（Callback）参数，服务端在上传完成后，发送同步的 POST 回调请求到 CallBack 中指定的第三方应用服务器，在服务器确认接受并返回结果后，才将所有结果返回给客户端。
关于上传回调的详细介绍，请参见上传回调。

示例代码 #

普通上传实现上传回调 #

// 导入 SDK, 当 TOS Node.JS SDK 版本小于 2.5.2 请把下方 TosClient 改成 TOS 导入
import { TosClient, TosClientError, TosServerError } from '@volcengine/tos-sdk';

// 创建客户端
const client = new TosClient({
  accessKeyId: process.env['TOS_ACCESS_KEY'],
  accessKeySecret: process.env['TOS_SECRET_KEY'],
  region: "Provide your region", // 填写 Bucket 所在地域。以华北2（北京)为例，则 "Provide your region" 填写为 cn-beijing。
  endpoint: "Provide your endpoint", // 填写域名地址
});

function handleError(error) {
  if (error instanceof TosClientError) {
    console.log('Client Err Msg:', error.message);
    console.log('Client Err Stack:', error.stack);
  } else if (error instanceof TosServerError) {
    console.log('Request ID:', error.requestId);
    console.log('Response Status Code:', error.statusCode);
    console.log('Response Header:', error.headers);
    console.log('Response Err Code:', error.code);
    console.log('Response Err Msg:', error.message);
  } else {
    console.log('unexpected exception, message: ', error);
  }
}

const bucketName = 'node-sdk-test-bucket';
async function main() {
  try {
    const callbackUrl = '*** Provide your callback url ***';
    const objectKey = '*** Provide your object key ***';

    // 设置上传回调参数
    // 可以根据需求设置 callback 参数
    const callback = `
    {
      "callbackUrl" : "${callbackUrl}", 
      "callbackBody" : ${'"{\\"bucket\\": ${bucket}, \\"object\\": ${object}, \\"key1\\": ${x:key1}}"'}, 
      "callbackBodyType" : "application/json"                
    }`;  // callback 的值需要进行 base64 编码
    // 配置相关变量参数
    const callbackVar = `
    {
      "x:key1" : "ceshi"
    }`;// callbackVar 的值需要进行 base64 编码
    const { requestId: putObjectRequestId } = await client.putObject({
      bucket: bucketName,
      key: objectKey,
      body: Buffer.from('object content'),
      callback: Buffer.from(callback).toString('base64'),
      callbackVar: Buffer.from(callbackVar).toString('base64'),
    });
    console.log('putObject Request ID: ', putObjectRequestId);
  } catch (error) {
    handleError(error);
  }
}

main();

分片上传实现上传回调 #

// 导入 SDK, 当 TOS Node.JS SDK 版本小于 2.5.2 请把下方 TosClient 改成 TOS 导入
import { TosClient, TosClientError, TosServerError } from '@volcengine/tos-sdk';
import fsp from 'fs/promises';

// 创建客户端
const client = new TosClient({
  accessKeyId: process.env['TOS_ACCESS_KEY'],
  accessKeySecret: process.env['TOS_SECRET_KEY'],
  region: "Provide your region", // 填写 Bucket 所在地域。以华北2（北京)为例，则 "Provide your region" 填写为 cn-beijing。
  endpoint: "Provide your endpoint", // 填写域名地址
});

function handleError(error) {
  if (error instanceof TosClientError) {
    console.log('Client Err Msg:', error.message);
    console.log('Client Err Stack:', error.stack);
  } else if (error instanceof TosServerError) {
    console.log('Request ID:', error.requestId);
    console.log('Response Status Code:', error.statusCode);
    console.log('Response Header:', error.headers);
    console.log('Response Err Code:', error.code);
    console.log('Response Err Msg:', error.message);
  } else {
    console.log('unexpected exception, message: ', error);
  }
}

async function main() {
  try {
    const bucketName = 'node-sdk-test-bucket';
    // 本地 example_dir 文件夹下的 multipartExample 文件
    const filePath = './example_dir/multipartExample';
    const callbackUrl = '*** Provide your callback url ***';
    const objectKey = '*** Provide your object key ***';

    // 设置上传回调参数
    // 可以根据需求设置 callback 参数
    const callback = `
    {
      "callbackUrl" : "${callbackUrl}", 
      "callbackBody" : ${'"{\\"bucket\\": ${bucket}, \\"object\\": ${object}, \\"key1\\": ${x:key1}}"'}, 
      "callbackBodyType" : "application/json"                
    }`; // callback 的值需要进行 base64 编码
    // 配置相关变量参数
    const callbackVar = `
    {
      "x:key1" : "ceshi"
    }`; // callbackVar 的值需要进行 base64 编码
    // 获取上传任务 ID
    const {
      data: { UploadId },
    } = await client.createMultipartUpload({
      bucket: bucketName,
      key: objectKey,
    });
    console.log('UploadId', UploadId);

    // 获取本地文件信息并准备进行分片
    const stats = await fsp.stat(filePath);
    // 文件总大小
    const totalSize = stats.size;

    let offset = 0;
    let partNumber = 1;
    const partsInfo = [];
    // 上传时指定分片大小
    const partSize = 5 * 1024 * 1024;

    while (offset < totalSize) {
      const uploadResult = await client.uploadPartFromFile({
        bucket: bucketName,
        key: objectKey,
        filePath,
        partNumber,
        uploadId: UploadId,
        offset,
        partSize,
      });
      const eTag = uploadResult.data.ETag;
      console.log(`partNumber${partNumber} Etag:`, eTag);
      partsInfo.push({
        partNumber,
        eTag,
      });
      partNumber++;
      offset += partSize;
    }

    console.log('parts information', partsInfo);

    // 完成分片上传
    const { data, requestId: completeMultipartUploadRequestId } = await client.completeMultipartUpload({
      bucket: bucketName,
      key: objectKey,
      uploadId: UploadId,
      parts: partsInfo,
      callback: Buffer.from(callback).toString('base64'),
      callbackVar: Buffer.from(callbackVar).toString('base64'),
    });

    console.log('completeMultipartUpload Request ID: ', completeMultipartUploadRequestId);
    console.log('result data:', data);
  } catch (error) {
    handleError(error);
  }
}

main();

#