直击痛点！一文带你搞定AWS S3大文件上传

如何将 AWS S3 文件上传集成到 JavaScript

引言

在数据爆炸的时代，我们经常需要上传视频、图像、音频等大文件。传统的文件上传方式往往效率低下且容易出错。AWS S3 作为一款对象存储服务，提供了高效、可靠的文件上传解决方案。本文将详细介绍如何将 AWS S3 大文件上传相关的 API 集成为 JavaScript 文件，涵盖多文件并行上传、文件分片上传、断点续传、文件分片合成、上传暂停、取消上传、文件上传进度条显示等功能。

一、多文件并行上传

多文件并行上传是指同时上传多个文件。这种方式可以大大提高上传效率，尤其是在上传大量小文件时。在 JavaScript 中，可以使用以下代码实现多文件并行上传：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const files = ['file1.txt', 'file2.txt', 'file3.txt'];

files.forEach((file) => {
  s3.upload({
    Bucket: 'my-bucket',
    Key: file,
    Body: fs.createReadStream(file),
  }, (err, data) => {
    if (err) {
      console.error(err);
    } else {
      console.log(`File ${file} uploaded successfully`);
    }
  });
});

二、文件分片上传

文件分片上传是指将大文件分成多个小块，然后分别上传这些小块。这种方式可以避免因为网络波动导致的上传失败。在 JavaScript 中，可以使用以下代码实现文件分片上传：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const file = 'large-file.txt';
const chunkSize = 10 * 1024 * 1024; // 10MB

const fileStream = fs.createReadStream(file);
const chunks = [];

fileStream.on('data', (chunk) => {
  chunks.push(chunk);
});

fileStream.on('end', () => {
  const numChunks = Math.ceil(fileStream.bytesRead / chunkSize);

  for (let i = 0; i < numChunks; i++) {
    const startByte = i * chunkSize;
    const endByte = Math.min(startByte + chunkSize, fileStream.bytesRead);
    const chunk = Buffer.concat(chunks.slice(i, i + 1));

    s3.upload({
      Bucket: 'my-bucket',
      Key: file,
      Body: chunk,
      PartNumber: i + 1,
    }, (err, data) => {
      if (err) {
        console.error(err);
      } else {
        console.log(`Part ${i + 1} of file ${file} uploaded successfully`);
      }
    });
  }
});

三、断点续传

断点续传是指在上传过程中出现网络中断时，能够从断点处继续上传。在 JavaScript 中，可以使用以下代码实现断点续传：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const file = 'large-file.txt';
const chunkSize = 10 * 1024 * 1024; // 10MB

const fileStream = fs.createReadStream(file);
const chunks = [];

fileStream.on('data', (chunk) => {
  chunks.push(chunk);
});

fileStream.on('end', () => {
  const numChunks = Math.ceil(fileStream.bytesRead / chunkSize);

  for (let i = 0; i < numChunks; i++) {
    const startByte = i * chunkSize;
    const endByte = Math.min(startByte + chunkSize, fileStream.bytesRead);
    const chunk = Buffer.concat(chunks.slice(i, i + 1));

    s3.upload({
      Bucket: 'my-bucket',
      Key: file,
      Body: chunk,
      PartNumber: i + 1,
      UploadId: 'my-upload-id', // Use the same UploadId for all parts
    }, (err, data) => {
      if (err) {
        console.error(err);
      } else {
        console.log(`Part ${i + 1} of file ${file} uploaded successfully`);
      }
    });
  }
});

四、文件分片合成

文件分片合成是指将上传的多个分片合并成一个完整的文件。在 JavaScript 中，可以使用以下代码实现文件分片合成：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const file = 'large-file.txt';
const numChunks = 10; // Number of chunks

const s3Client = new S3();

const params = {
  Bucket: 'my-bucket',
  Key: file,
  UploadId: 'my-upload-id', // Use the same UploadId for all parts
  Parts: [] // Array of Part objects
};

for (let i = 0; i < numChunks; i++) {
  params.Parts.push({
    PartNumber: i + 1,
    ETag: 'etag-' + i
  });
}

s3Client.completeMultipartUpload(params, (err, data) => {
  if (err) {
    console.error(err);
  } else {
    console.log(`File ${file} uploaded successfully`);
  }
});

五、上传暂停和取消

上传暂停和取消是指在上传过程中可以暂停或取消上传。在 JavaScript 中，可以使用以下代码实现上传暂停和取消：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const file = 'large-file.txt';
const chunkSize = 10 * 1024 * 1024; // 10MB

const fileStream = fs.createReadStream(file);
const chunks = [];

fileStream.on('data', (chunk) => {
  chunks.push(chunk);
});

fileStream.on('end', () => {
  const numChunks = Math.ceil(fileStream.bytesRead / chunkSize);

  for (let i = 0; i < numChunks; i++) {
    const startByte = i * chunkSize;
    const endByte = Math.min(startByte + chunkSize, fileStream.bytesRead);
    const chunk = Buffer.concat(chunks.slice(i, i + 1));

    s3.upload({
      Bucket: 'my-bucket',
      Key: file,
      Body: chunk,
      PartNumber: i + 1,
      UploadId: 'my-upload-id', // Use the same UploadId for all parts
    }, (err, data) => {
      if (err) {
        console.error(err);
      } else {
        console.log(`Part ${i + 1} of file ${file} uploaded successfully`);
      }
    });
  }
});

// Pause the upload
s3.abortMultipartUpload({
  Bucket: 'my-bucket',
  Key: file,
  UploadId: 'my-upload-id',
}, (err, data) => {
  if (err) {
    console.error(err);
  } else {
    console.log(`Upload of file ${file} paused successfully`);
  }
});

// Cancel the upload
s3.abortMultipartUpload({
  Bucket: 'my-bucket',
  Key: file,
  UploadId: 'my-upload-id',
}, (err, data) => {
  if (err) {
    console.error(err);
  } else {
    console.log(`Upload of file ${file} cancelled successfully`);
  }
});

六、文件上传进度条

文件上传进度条是指在上传过程中显示上传进度。在 JavaScript 中，可以使用以下代码实现文件上传进度条：

const S3 = require('aws-sdk/clients/s3');
const s3 = new S3();

const file = 'large-file.txt';
const chunkSize = 10 * 1024 * 1024; // 10MB

const fileStream = fs.createReadStream(file);
const chunks = [];

fileStream.on('data', (chunk) => {
  chunks.push(chunk);
});

fileStream.on('end', () => {
  const numChunks = Math.ceil(fileStream.bytesRead / chunkSize);

  const progressBar = document.createElement('progress');