@eggjs/multipart

中文文档
5.1.0发布于 2026/10/07MITTypeScriptES Module构建来源已验证近 30 天下载 4746

Multipart plugin for egg

原始使用文档
文档目录15 节
  1. Whitelist of file extensions
  2. fileSize
  3. Custom Config
  4. Examples
  5. file mode: the easy way
  6. Enable file mode on config
  7. Upload One File
  8. Upload Multiple Files
  9. stream mode: the hard way
  10. Use with for await...of
  11. Upload One File (DEPRECATED)
  12. Upload Multiple Files (DEPRECATED)
  13. Support file and stream mode in the same time
  14. License
  15. Contributors

@eggjs/multipart

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Use co-busboy to upload file by streaming and process it without save to disk(using the stream mode).

Just use ctx.multipart() to got file stream, then pass to image processing module such as gm or upload to cloud storage such as oss.

Whitelist of file extensions

For security, if uploading file extension is not in white list, will response as 400 Bad request.

Default Whitelist:

const whitelist = [
  // images
  '.jpg',
  '.jpeg', // image/jpeg
  '.png', // image/png, image/x-png
  '.gif', // image/gif
  '.bmp', // image/bmp
  '.wbmp', // image/vnd.wap.wbmp
  '.webp',
  '.tif',
  '.psd',
  // text
  '.svg',
  '.js',
  '.jsx',
  '.json',
  '.css',
  '.less',
  '.html',
  '.htm',
  '.xml',
  // tar
  '.zip',
  '.gz',
  '.tgz',
  '.gzip',
  // video
  '.mp3',
  '.mp4',
  '.avi',
];

fileSize

The default fileSize that multipart can accept is 10mb. if you upload a large file, you should specify this config.

// config/config.default.js
exports.multipart = {
  fileSize: '50mb',
};

Custom Config

Developer can custom additional file extensions:

// config/config.default.js
exports.multipart = {
  // will append to whilelist
  fileExtensions: ['.foo', '.apk'],
};

Can also override built-in whitelist, such as only allow png:

// config/config.default.js
exports.multipart = {
  whitelist: ['.png'],
};

Or by function:

exports.multipart = {
  whitelist: (filename) => ['.png'].includes(path.extname(filename) || ''),
};

Note: if define whitelist, then fileExtensions will be ignored.

Examples

More examples please follow:

file mode: the easy way

If you don't know the Node.js Stream work, maybe you should use the file mode to get started.

The usage very similar to bodyParser.

  • ctx.request.body: Get all the multipart fields and values, except file.
  • ctx.request.files: Contains all file from the multipart request, it's an Array object.

WARNING: you should remove the temporary upload files after you use it, the async ctx.cleanupRequestFiles() method will be very helpful.

Enable file mode on config

You need to set config.multipart.mode = 'file' to enable file mode:

// config/config.default.js
exports.multipart = {
  mode: 'file',
};

After file mode enable, egg will remove the old temporary files(don't include today's files) on 04:30 AM every day by default.

config.multipart = {
  mode: 'file',
  tmpdir: path.join(os.tmpdir(), 'egg-multipart-tmp', appInfo.name),
  cleanSchedule: {
    // run tmpdir clean job on every day 04:30 am
    // cron style see https://github.com/eggjs/egg-schedule#cron-style-scheduling
    cron: '0 30 4 * * *',
    disable: false,
  },
};

Default will use the last field which has same name, if need the all fields value, please set allowArrayField in config.

// config/config.default.js
exports.multipart = {
  mode: 'file',
  allowArrayField: true,
};

Upload One File

<form method="POST" action="/upload?_csrf={{ ctx.csrf | safe }}" enctype="multipart/form-data">
  title: <input name="title" /> file: <input name="file" type="file" />
  <button type="submit">Upload</button>
</form>

Controller which hanlder POST /upload:

// app/controller/upload.js
const Controller = require('egg').Controller;
const fs = require('mz/fs');

module.exports = class extends Controller {
  async upload() {
    const { ctx } = this;
    const file = ctx.request.files[0];
    const name = 'egg-multipart-test/' + path.basename(file.filename);
    let result;
    try {
      // process file or upload to cloud storage
      result = await ctx.oss.put(name, file.filepath);
    } finally {
      // remove tmp files and don't block the request's response
      // cleanupRequestFiles won't throw error even remove file io error happen
      ctx.cleanupRequestFiles();
      // remove tmp files before send response
      // await ctx.cleanupRequestFiles();
    }

    ctx.body = {
      url: result.url,
      // get all field values
      requestBody: ctx.request.body,
    };
  }
};

Upload Multiple Files

<form method="POST" action="/upload?_csrf={{ ctx.csrf | safe }}" enctype="multipart/form-data">
  title: <input name="title" /> file1: <input name="file1" type="file" /> file2: <input name="file2" type="file" />
  <button type="submit">Upload</button>
</form>

Controller which hanlder POST /upload:

// app/controller/upload.js
const Controller = require('egg').Controller;
const fs = require('mz/fs');

module.exports = class extends Controller {
  async upload() {
    const { ctx } = this;
    console.log(ctx.request.body);
    console.log('got %d files', ctx.request.files.length);
    for (const file of ctx.request.files) {
      console.log('field: ' + file.fieldname);
      console.log('filename: ' + file.filename);
      console.log('encoding: ' + file.encoding);
      console.log('mime: ' + file.mime);
      console.log('tmp filepath: ' + file.filepath);
      let result;
      try {
        // process file or upload to cloud storage
        result = await ctx.oss.put('egg-multipart-test/' + file.filename, file.filepath);
      } finally {
        // remove tmp files and don't block the request's response
        // cleanupRequestFiles won't throw error even remove file io error happen
        ctx.cleanupRequestFiles([file]);
      }
      console.log(result);
    }
  }
};

stream mode: the hard way

If you're well-known about know the Node.js Stream work, you should use the stream mode.

Use with for await...of

<form method="POST" action="/upload?_csrf={{ ctx.csrf | safe }}" enctype="multipart/form-data">
  title: <input name="title" /> file1: <input name="file1" type="file" /> file2: <input name="file2" type="file" />
  <button type="submit">Upload</button>
</form>

Controller which hanlder POST /upload:

// app/controller/upload.js
const { Controller } = require('egg');
const fs = require('fs');
const stream = require('stream');
const util = require('util');
const { randomUUID } = require('crypto');
const pipeline = util.promisify(stream.pipeline);

module.exports = class UploadController extends Controller {
  async upload() {
    const parts = this.ctx.multipart();
    const fields = {};
    const files = {};

    for await (const part of parts) {
      if (Array.isArray(part)) {
        // fields
        console.log('field: ' + part[0]);
        console.log('value: ' + part[1]);
      } else {
        // otherwise, it's a stream
        const { filename, fieldname, encoding, mime } = part;

        console.log('field: ' + fieldname);
        console.log('filename: ' + filename);
        console.log('encoding: ' + encoding);
        console.log('mime: ' + mime);

        // how to handler?
        // 1. save to tmpdir with pipeline
        // 2. or send to oss
        // 3. or just consume it with another for await

        // WARNING: You should almost never use the origin filename as it could contain malicious input.
        const targetPath = path.join(os.tmpdir(), randomUUID() + path.extname(filename));
        await pipeline(part, createWriteStream(targetPath)); // use `pipeline` not `pipe`
      }
    }

    this.ctx.body = 'ok';
  }
};

Upload One File (DEPRECATED)

You can got upload stream by ctx.getFileStream*().

<form method="POST" action="/upload?_csrf={{ ctx.csrf | safe }}" enctype="multipart/form-data">
  title: <input name="title" /> file: <input name="file" type="file" />
  <button type="submit">Upload</button>
</form>

Controller which handler POST /upload:

// app/controller/upload.js
const path = require('node:path');
const { sendToWormhole } = require('stream-wormhole');
const { Controller } = require('egg');

module.exports = class extends Controller {
  async upload() {
    const { ctx } = this;
    // file not exists will response 400 error
    const stream = await ctx.getFileStream();
    const name = 'egg-multipart-test/' + path.basename(stream.filename);
    // process file or upload to cloud storage
    const result = await ctx.oss.put(name, stream);

    ctx.body = {
      url: result.url,
      // process form fields by `stream.fields`
      fields: stream.fields,
    };
  }

  async uploadNotRequiredFile() {
    const { ctx } = this;
    // file not required
    const stream = await ctx.getFileStream({ requireFile: false });
    let result;
    if (stream.filename) {
      const name = 'egg-multipart-test/' + path.basename(stream.filename);
      // process file or upload to cloud storage
      const result = await ctx.oss.put(name, stream);
    } else {
      // must consume the empty stream
      await sendToWormhole(stream);
    }

    ctx.body = {
      url: result && result.url,
      // process form fields by `stream.fields`
      fields: stream.fields,
    };
  }
};

Upload Multiple Files (DEPRECATED)

<form method="POST" action="/upload?_csrf={{ ctx.csrf | safe }}" enctype="multipart/form-data">
  title: <input name="title" /> file1: <input name="file1" type="file" /> file2: <input name="file2" type="file" />
  <button type="submit">Upload</button>
</form>

Controller which hanlder POST /upload:

// app/controller/upload.js
const Controller = require('egg').Controller;

module.exports = class extends Controller {
  async upload() {
    const { ctx } = this;
    const parts = ctx.multipart();
    let part;
    while ((part = await parts()) != null) {
      if (part.length) {
        // arrays are busboy fields
        console.log('field: ' + part[0]);
        console.log('value: ' + part[1]);
        console.log('valueTruncated: ' + part[2]);
        console.log('fieldnameTruncated: ' + part[3]);
      } else {
        if (!part.filename) {
          // user click `upload` before choose a file,
          // `part` will be file stream, but `part.filename` is empty
          // must handler this, such as log error.
          continue;
        }
        // otherwise, it's a stream
        console.log('field: ' + part.fieldname);
        console.log('filename: ' + part.filename);
        console.log('encoding: ' + part.encoding);
        console.log('mime: ' + part.mime);
        const result = await ctx.oss.put('egg-multipart-test/' + part.filename, part);
        console.log(result);
      }
    }
    console.log('and we are done parsing the form!');
  }
};

Support file and stream mode in the same time

If the default mode is stream, use the fileModeMatch options to match the request urls switch to file mode.

config.multipart = {
  mode: 'stream',
  // let POST /upload_file request use the file mode, other requests use the stream mode.
  fileModeMatch: /^\/upload_file$/,
  // or glob
  // fileModeMatch: '/upload_file',
};

NOTICE: fileModeMatch options only work on stream mode.

License

MIT

Contributors

Contributors

Made with contributors-img.

版本与发布记录

@eggjs/multipart 共发布 52 个版本,首次发布于 2025/02/03;过去 12 个月发布了 33 个版本。最新版本附带 npm provenance 构建来源证明,可追溯到公开的 CI 构建记录。

版本发布日期距今
5.1.0latest2026/10/071 个月前
5.0.22026/10/061 个月前
5.0.2-rc.1rc2026/10/061 个月前
5.0.2-rc.02026/09/231 个月前
5.0.2-beta.27beta2026/09/201 个月前
5.0.2-beta.262026/08/073 个月前

关于 @eggjs/multipart 的常见问题

@eggjs/multipart 是什么?

Multipart plugin for egg

如何安装 @eggjs/multipart?

在项目目录运行 npm install @eggjs/multipart,或使用 pnpm add / yarn add / bun add。它还需要宿主项目提供 peer 依赖:egg(4.2.0)。npm 7 及以上与 pnpm 8 及以上默认会自动安装必需的 peer 依赖,Yarn 需要手动安装。

@eggjs/multipart 支持 TypeScript 吗?

支持。包内自带 TypeScript 类型声明(package.json 声明了 types 入口),安装后即可获得类型提示,无需再安装 @types 包。

@eggjs/multipart 支持 ESM 还是 CommonJS?

以 ES Module 形式发布,推荐使用 import 引入。在 CommonJS 项目中,Node.js 20.19+ / 22.12+ 可以直接 require() 不含顶层 await 的 ES Module,更早的版本需要改用动态 import()。

@eggjs/multipart 需要什么版本的 Node.js?

package.json 的 engines 字段要求 Node.js >= 22.18.0。版本不符时 npm 默认只给出警告,开启 engine-strict 后会拒绝安装。

@eggjs/multipart 可以商用吗?

@eggjs/multipart 使用 MIT 许可。宽松许可:允许商业使用、修改和再分发,通常只需在分发时保留原版权与许可声明。以上为概括,不构成法律意见,请以许可原文为准。

@eggjs/multipart 的下载量有多少?

根据 npm 官方下载统计,@eggjs/multipart 在 2026/10/13 – 2026/11/11 这 30 天内被下载 4,746 次,日均约 158 次。下载量会把 CI 构建、镜像同步和作为其他包依赖的安装一并计入,适合横向比较热度,不能直接等同于使用人数。

@eggjs/multipart 还在维护吗?

最新版本 5.1.0 发布于 2026/10/07(1 个月前);至今共发布 52 个版本,其中过去 12 个月发布了 33 个;首次发布于 2025/02/03。发布频率只是参考信号:功能稳定的工具可能很少需要更新,建议结合源码仓库的 issue 和提交记录判断。