首页 > 解决方案 > express 中的 multer-s3 上传速度非常慢

问题描述

在我的 express 应用程序中通过 multer-s3 将文件上传到 S3 速度非常慢(200kb 需要 10 秒,延迟与文件大小有关)。问题是 multer-s3 但有人可以告诉如何进一步调试库中发生的事情吗?不再支持将 onFileUploadStart 等传递给 multer。我不知道如何在 multer-s3 正在做什么以及在哪个阶段引起延迟。

问题不在于 AWS S3,因为从 CLI 上传速度非常快,也不是 multer,因为上传到本地磁盘也很快。任何直接的 S3 javascript 操作也可以按预期快速运行。

尝试关闭 multer 的内容自动输入功能,但效果不大。

var upload = multer({
  storage: multerS3({
    s3: s3,
    bucket: bucketName,
    acl: 'public-read',
    contentType: multerS3.AUTO_CONTENT_TYPE,
    metadata: function (req, file, cb) {
      cb(null, {fieldName: file.fieldname});
    },
    key: function (req, file, cb) {
      cb(null, Date.now().toString() + "-" + file.originalname);
    }
  },)
})

router.post('/', upload.array('files'), function(req, res, next) {
  console.log('Successfully uploaded ' + req.files.length + ' files!');
});

Want to have sub-second latency as I do with direct AWS CLI upload or using multer to store to local disk, takes 10 seconds to minute or more on sub-MB files.

标签: node.jsexpressmultermulter-s3

解决方案


获得洞察力的一种方法是在响应套接字上代理 write 函数,并检查它是如何被调用的:

var upload = multer({
  storage: multerS3({
    s3: s3,
    bucket: bucketName,
    acl: 'public-read',
    contentType: multerS3.AUTO_CONTENT_TYPE,
    metadata: function (req, file, cb) {
      cb(null, {fieldName: file.fieldname});
    },
    key: function (req, file, cb) {
      cb(null, Date.now().toString() + "-" + file.originalname);
    }
  },)
})

router.post('/'
(req, res, next) => { // debug middleware
  const write = res.socket.write;
  res.socket.write = (function(...args) {
    // inspect args, look at the time between invocations of write
    // also check the size of the chunks being passed to write
    return write(...args)
  }).bind(res.socket);
  next();
}
, upload.array('files'), function(req, res, next) {
  console.log('Successfully uploaded ' + req.files.length + ' files!');
});

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