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リクエストでNode.jsのダウンロードの進行状況を取得する

Node module requestを使用してアプリケーションファイルをダウンロードするアップデーターを作成しています。使用方法chunk.length残りのファイルサイズを推定するには？コードの一部を次に示します。

var file_url = 'http://foo.com/bar.Zip';
var out = fs.createWriteStream('baz.Zip');

var req = request({
    method: 'GET',
    uri: file_url
});

req.pipe(out);

req.on('data', function (chunk) {
    console.log(chunk.length);
});

req.on('end', function() {
    //Do something
});
node.jsdownloadrequestprogress
24
Jack Guy

これにより、必要な合計が得られます。

req.on( 'response', function ( data ) {
    console.log( data.headers[ 'content-length' ] );
} );

コンテンツの長さは9404541

24
fakewaffle
function download(url, callback, encoding){
        var request = http.get(url, function(response) {
            if (encoding){
                response.setEncoding(encoding);
            }
            var len = parseInt(response.headers['content-length'], 10);
            var body = "";
            var cur = 0;
            var obj = document.getElementById('js-progress');
            var total = len / 1048576; //1048576 - bytes in  1Megabyte

            response.on("data", function(chunk) {
                body += chunk;
                cur += chunk.length;
                obj.innerHTML = "Downloading " + (100.0 * cur / len).toFixed(2) + "% " + (cur / 1048576).toFixed(2) + " mb\r" + ".<br/> Total size: " + total.toFixed(2) + " mb";
            });

            response.on("end", function() {
                callback(body);
                obj.innerHTML = "Downloading complete";
            });

            request.on("error", function(e){
                console.log("Error: " + e.message);
            });

        });
    };
17
Anja Ishmukhametova

Cool node-request-progress モジュールを使用すると、es2015で次のようなことができます。

import { createWriteStream } from 'fs'
import request from 'request'
import progress from 'request-progress'

progress(request('http://foo.com/bar.Zip'))
 .on('progress', state => {

   console.log(state)

   /*
   {
       percentage: 0.5,        // Overall percentage (between 0 to 1)
       speed: 554732,          // The download speed in bytes/sec
       size: {
         total: 90044871,      // The total payload size in bytes
         transferred: 27610959 // The transferred payload size in bytes
       },
       time: {
         elapsed: 36.235,      // The total elapsed seconds since the start (3 decimals)
         remaining: 81.403     // The remaining seconds to finish (3 decimals)
       }
   }
   */

  })
  .on('error', err => console.log(err))
  .on('end', () => {})
  .pipe(createWriteStream('bar.Zip'))
6
Balthazar

「リクエスト」モジュールを使用しており、追加のモジュールを使用せずにダウンロード率を表示する場合は、次のコードを使用できます。

function getInstallerFile (installerfileURL) {

    // Variable to save downloading progress
    var received_bytes = 0;
    var total_bytes = 0;

    var outStream = fs.createWriteStream(INSTALLER_FILE);

    request
        .get(installerfileURL)
            .on('error', function(err) {
                console.log(err);
            })
            .on('response', function(data) {
                total_bytes = parseInt(data.headers['content-length']);
            })
            .on('data', function(chunk) {
                received_bytes += chunk.length;
                showDownloadingProgress(received_bytes, total_bytes);
            })
            .pipe(outStream);
};

function showDownloadingProgress(received, total) {
    var percentage = ((received * 100) / total).toFixed(2);
    process.stdout.write((platform == 'win32') ? "\033[0G": "\r");
    process.stdout.write(percentage + "% | " + received + " bytes downloaded out of " + total + " bytes.");
}
3
Rohit Pandey

必要なことだけを行うモジュールを作成しました： status-bar 。

var bar = statusBar.create ({ total: res.headers["content-length"] })
    .on ("render", function (stats){
      websockets.send (stats);
    })

req.pipe (bar);
3
Gabriel Llamas

誰かが他のライブラリを使用せずに進行状況を知りたいだけでリクエストしたい場合は、次のメソッドを使用できます：

function downloadFile(file_url , targetPath){
    // Save variable to know progress
    var received_bytes = 0;
    var total_bytes = 0;

    var req = request({
        method: 'GET',
        uri: file_url
    });

    var out = fs.createWriteStream(targetPath);
    req.pipe(out);

    req.on('response', function ( data ) {
        // Change the total bytes value to get progress later.
        total_bytes = parseInt(data.headers['content-length' ]);
    });

    req.on('data', function(chunk) {
        // Update the received bytes
        received_bytes += chunk.length;

        showProgress(received_bytes, total_bytes);
    });

    req.on('end', function() {
        alert("File succesfully downloaded");
    });
}

function showProgress(received,total){
    var percentage = (received * 100) / total;
    console.log(percentage + "% | " + received + " bytes out of " + total + " bytes.");
    // 50% | 50000 bytes received out of 100000 bytes.
}

downloadFile("https://static.pexels.com/photos/36487/above-adventure-aerial-air.jpg","c:/path/to/local-image.jpg");

received_bytes変数は、送信されたすべてのチャンク長の合計を保存し、total_bytes、進行状況が取得されます。

2
Carlos Delgado