如何将缓冲区拆分为块

Question

我已尝试解决此问题，但无济于事。我正在将文件上传到服务器。所以，我正在使用 fs.readfilesync(file location path) 来读取文件。当我 console.log 结果我得到一个缓冲区。我的目标是尝试将此缓冲区拆分为 10mbs 大小，因为如果有人上传 100mb 文件，我需要使用公式 100mb / 10mb 拆分该文件。这样我就可以一次获得可以发送到服务器的特定块。所以我的挑战是，我如何将此缓冲区细分为 chunks 。到目前为止，这是我尝试过但一点也不积极的：

缓冲区

缓冲区(1011712) [6, 6, 237, 245, 216, 29, 70, 229, 189, 49, 239, 231, 254, 116, 183, 29, 68, 79, 67, 85, 77, 69, 78, 84, 1, 112, 15, 0, 0, 16, 0, 0, 0, 4, 0, 0, 0, 3, 0, 0, 0, 141, 68, 59, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...]

  var fileToUpload = fs.readFileSync(folderPath)
                var len = fileToUpload.byteLength
                var fileToUploadBuf = new Uint16Array(fileToUpload)

                for (let i = 0; i < len;) {
                    var chunk = fileToUploadBuf.slice(i, 'how do I get bytes size')
                    if (chunk.length) {
                        console.log('the lenght of chunk is', chunk)
                        i += chunk.length
                    }
                }

Answer 1

我认为这不可能，我认为您需要将文件作为流发送给您的服务器

MDN Transfer-Encoding

这里附上了一个将文件流式传输到 S3 存储的服务器的示例 Node.Js

包.json

{
    "name": "custom-server",
    "dependencies": {
        "express": "4.13.3",
        "request": "2.64.0",
        "multiparty": "4.1.2",
        "form-data": "1.0.0-rc3"
    }
}

索引.js

var app = require("express")();
var multiparty = require("multiparty");

app.post("/submit", function(httpRequest, httpResponse, next){

    var form = new multiparty.Form();

    form.on("part", function(part){
        if(part.filename)
        {
            var FormData = require("form-data");
            var request = require("request")
            var form = new FormData();

            form.append("thumbnail", part, {filename: part.filename,contentType: part["content-type"]});

            var r = request.post("http://localhost:7070/store", { "headers": {"transfer-encoding": "chunked"} }, function(err, res, body){
                httpResponse.send(res);
            });
           
            r._form = form
        }
    })

    form.on("error", function(error){
        console.log(error);
    })

    form.parse(httpRequest);   
   
});

app.get("/", function(httpRequest, httpResponse, next){
    httpResponse.send("<form action='http://localhost:9090/submit' method='post' enctype='multipart/form-data'><input type='file' name='thumbnail' /><input type='submit' value='Submit' /></form>");
});

app.listen(9090);