node.js - KoaJS 如何从多部分表单数据中获取文件？

Question

当我发布多部分表单时，

<form name="acount_manage"  action="/update" enctype="multipart/form-data" method="post">
    <input type="file" name="file">
</form>

它抛出:

Error: Unsupported content-type: multipart/form-data
at Object.<anonymous> (e:\...\node_modules\co-body\lib\any.js:51:15)

任何.js:

/**
 * Module dependencies.
 */

var json = require('./json');
var form = require('./form');
var text = require('./text');

var JSON_CONTENT_TYPES = [
  'application/json',
  'application/json-patch+json',
  'application/vnd.api+json',
  'application/csp-report',
  'application/ld+json'

];

/**
 * Return a a thunk which parses form and json requests
 * depending on the Content-Type.
 *
 * Pass a node request or an object with `.req`,
 * such as a koa Context.
 *
 * @param {Request} req
 * @param {Options} [opts]
 * @return {Function}
 * @api public
 */

module.exports = function(req, opts){
  req = req.req || req;

  // parse Content-Type
  var type = req.headers['content-type'] || '';
  type = type.split(';')[0];

  // json
  if (~JSON_CONTENT_TYPES.indexOf(type)) return json(req, opts);

  // form
  if ('application/x-www-form-urlencoded' == type) return form(req, opts);

  // text
  if ('text/plain' == type) return text(req, opts);

  // invalid
  return function(done){
    var message = type ? 'Unsupported content-type: ' + type : 'Missing content-type';
    var err = new Error(message);
    err.status = 415;
    done(err);
  };
};

然后，我改了代码

if ('application/x-www-form-urlencoded' == type) return form(req, opts);

到

if ('application/x-www-form-urlencoded' == type || 'multipart/form-data'==type) return form(req, opts);

没有错误，但我无法获取请求的数据:

debug(this.request.files.file);

结果未定义。

我正在使用 KoaJs。

Answer 1

对于 koa 2，尝试 async-busboy将请求正文解析为 co-busboy不适用于基于 promise 的异步。

文档中的示例:

import asyncBusboy from 'async-busboy';

// Koa 2 middleware
async function(ctx, next) {
  const {files, fields} = await asyncBusboy(ctx.req);

  // Make some validation on the fields before upload to S3
  if ( checkFiles(fields) ) {
    files.map(uploadFilesToS3)
  } else {
    return 'error';
  }
}