1. Requirements: Upload a large file [video] and process it with Nodejs;
2. The front-end uses resumable to slice and upload the video, and the back-end uses formidable to useBufferdeal with

Problems encountered [Use a text as an example to upload]:

1. 后端写入成功后，无法打开文件【自动添加POST中相关的值】

X.Code part

1.app.js

app.post('/upload', function(req, res){ var form = new formidable.IncomingForm(); //后缀名 form.keepExtensions = true; //保存路径 form.uploadDir = './'; form.parse(req, function(err, fields, files) { //console.log(util.inspect({fields: fields, files: files})); }); var dd=[],ll=0; form.handlePart=function(part) { var dd=[],ll=0; //Buffer加入数组 part.on('data', function(data) { if (data.length == 0) { return; } dd.push(data); ll+=data.length; }); part.on('end', function() { //获取文件名 var p = './' + req.query.resumableFilename; fs.open(p, 'a', function (err, fd) { if (err) { throw err; } var writeBuffer = dd, offset = 0, len = writeBuffer.length, filePostion = null; //写人Buffer fs.write(fd, Buffer.concat(dd, ll), 0, ll, filePostion, function(){ }) }); }); } });

2.Charles packet capture data

POST /upload?resumableChunkNumber=1&resumableChunkSize=1048576&resumableCurrentChunkSize=393&resumableTotalSize=393&resumableType=text%2Frtf&resumableIdentifier=393-rtf&resumableFilename=%E6%96%87%E6%9C%AC.rtf&resumableRelativePath=%E6%96%87%E6%9C%AC.rtf&resumableTotalChunks=1 HTTP/1.1 Host: 127.0.0.1:4000 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="file"; filename="文本.rtf" Content-Type: application/octet-stream ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableChunkNumber" 1 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableChunkSize" 1048576 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableCurrentChunkSize" 393 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableTotalSize" 393 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableType" text/rtf ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableIdentifier" 393-rtf ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableFilename" 文本.rtf ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableRelativePath" 文本.rtf ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="resumableTotalChunks" 1 ------WebKitFormBoundaryeLW6trgJbBaZlvgP Content-Disposition: form-data; name="file"; filename="文本.rtf" Content-Type: application/octet-stream {\rtf1\ansi\ansicpg936\cocoartf1504 {\fonttbl\f0\fnil\fcharset134 PingFangSC-Regular;} {\colortbl;\red255\green255\blue255;} {\*\expandedcolortbl;\csgray\c100000;} \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0 \pard\tx566\tx1133\tx1700\tx2267\tx2834\tx3401\tx3968\tx4535\tx5102\tx5669\tx6236\tx6803\pardirnatural\partightenfactor0 \f0\fs24 \cf0 \'c4\'e3\'ba\'c3} ------WebKitFormBoundaryeLW6trgJbBaZlvgP--

3. Data obtained by the server

Write the content of the file

11048576393393text/rtf393-rtf文本.rtf文本.rtf1{\rtf1\ansi\ansicpg936\cocoartf1504 {\fonttbl\f0\fnil\fcharset134 PingFangSC-Regular;} {\colortbl;\red255\green255\blue255;} {\*\expandedcolortbl;\csgray\c100000;} \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0 \pard\tx566\tx1133\tx1700\tx2267\tx2834\tx3401\tx3968\tx4535\tx5102\tx5669\tx6236\tx6803\pardirnatural\partightenfactor0 \f0\fs24 \cf0 \'c4\'e3\'ba\'c3}

4.The problem

The first part of the file saved on the server side has more data than the data submitted by the front end.The following content`Please enter the code

11048576393393text/rtf393-rtf文本.rtf文本.rtf1

This content is the splicing

of the values corresponding to the URL parameters inPOST, which is the judgment and segmentation of the boundary in the http protocol.
If you manually delete this part of the characters, the file can be opened

problem lies in

1. How to prevent it from automatically adding this attribute?
2. Is it possible to follow this writing method when uploading large videos?

If you have any ideas, please give me some advice, thank you very much