就像Michelle Tilley说的，但是要有适当的控制流:

var http = require('http');
var fs = require('fs');

var download = function(url, dest, cb) {
  var file = fs.createWriteStream(dest);
  http.get(url, function(response) {
    response.pipe(file);
    file.on('finish', function() {
      file.close(cb);
    });
  });
}

如果不等待finish事件，幼稚的脚本可能最终得到一个不完整的文件。

编辑:感谢@Augusto Roman指出cb应该传递到文件。Close，没有显式调用。

也许node.js已经改变了，但似乎其他解决方案(使用node v8.1.2)有一些问题:

You don't need to call file.close() in the finish event. Per default the fs.createWriteStream is set to autoClose: https://nodejs.org/api/fs.html#fs_fs_createwritestream_path_options file.close() should be called on error. Maybe this is not needed when the file is deleted (unlink()), but normally it is: https://nodejs.org/api/stream.html#stream_readable_pipe_destination_options Temp file is not deleted on statusCode !== 200 fs.unlink() without a callback is deprecated (outputs warning) If dest file exists; it is overridden

下面是一个修改后的解决方案(使用ES6和promises)，它可以处理这些问题。

const http = require("http");
const fs = require("fs");

function download(url, dest) {
    return new Promise((resolve, reject) => {
        const file = fs.createWriteStream(dest, { flags: "wx" });

        const request = http.get(url, response => {
            if (response.statusCode === 200) {
                response.pipe(file);
            } else {
                file.close();
                fs.unlink(dest, () => {}); // Delete temp file
                reject(`Server responded with ${response.statusCode}: ${response.statusMessage}`);
            }
        });

        request.on("error", err => {
            file.close();
            fs.unlink(dest, () => {}); // Delete temp file
            reject(err.message);
        });

        file.on("finish", () => {
            resolve();
        });

        file.on("error", err => {
            file.close();

            if (err.code === "EEXIST") {
                reject("File already exists");
            } else {
                fs.unlink(dest, () => {}); // Delete temp file
                reject(err.message);
            }
        });
    });
}

对于那些寻找es6风格的基于承诺的方式的人来说，我猜它会是这样的:

var http = require('http');
var fs = require('fs');

function pDownload(url, dest){
  var file = fs.createWriteStream(dest);
  return new Promise((resolve, reject) => {
    var responseSent = false; // flag to make sure that response is sent only once.
    http.get(url, response => {
      response.pipe(file);
      file.on('finish', () =>{
        file.close(() => {
          if(responseSent)  return;
          responseSent = true;
          resolve();
        });
      });
    }).on('error', err => {
        if(responseSent)  return;
        responseSent = true;
        reject(err);
    });
  });
}

//example
pDownload(url, fileLocation)
  .then( ()=> console.log('downloaded file no issues...'))
  .catch( e => console.error('error while downloading', e));

这里还有另一种方法来处理它没有第三方依赖，也搜索重定向:

        var download = function(url, dest, cb) {
            var file = fs.createWriteStream(dest);
            https.get(url, function(response) {
                if ([301,302].indexOf(response.statusCode) !== -1) {
                    body = [];
                    download(response.headers.location, dest, cb);
                  }
              response.pipe(file);
              file.on('finish', function() {
                file.close(cb);  // close() is async, call cb after close completes.
              });
            });
          }

您可以创建一个HTTP GET请求，并将其响应管道到可写文件流:

const http = require('http'); // or 'https' for https:// URLs
const fs = require('fs');

const file = fs.createWriteStream("file.jpg");
const request = http.get("http://i3.ytimg.com/vi/J---aiyznGQ/mqdefault.jpg", function(response) {
   response.pipe(file);

   // after download completed close filestream
   file.on("finish", () => {
       file.close();
       console.log("Download Completed");
   });
});

如果您希望支持在命令行上收集信息(比如指定目标文件或目录或URL)，可以使用类似Commander的工具。

更详细的解释在https://sebhastian.com/nodejs-download-file/

现代版本(ES6, Promise, Node 12。X +)适用于https/http。它还支持重定向302和301。我决定不使用第三方库，因为它可以很容易地使用标准Node.js库。

// download.js
import fs from 'fs'
import https from 'https'
import http from 'http'
import { basename } from 'path'
import { URL } from 'url'

const TIMEOUT = 10000

function download (url, dest) {
  const uri = new URL(url)
  if (!dest) {
    dest = basename(uri.pathname)
  }
  const pkg = url.toLowerCase().startsWith('https:') ? https : http

  return new Promise((resolve, reject) => {
    const request = pkg.get(uri.href).on('response', (res) => {
      if (res.statusCode === 200) {
        const file = fs.createWriteStream(dest, { flags: 'wx' })
        res
          .on('end', () => {
            file.end()
            // console.log(`${uri.pathname} downloaded to: ${path}`)
            resolve()
          })
          .on('error', (err) => {
            file.destroy()
            fs.unlink(dest, () => reject(err))
          }).pipe(file)
      } else if (res.statusCode === 302 || res.statusCode === 301) {
        // Recursively follow redirects, only a 200 will resolve.
        download(res.headers.location, dest).then(() => resolve())
      } else {
        reject(new Error(`Download request failed, response status: ${res.statusCode} ${res.statusMessage}`))
      }
    })
    request.setTimeout(TIMEOUT, function () {
      request.abort()
      reject(new Error(`Request timeout after ${TIMEOUT / 1000.0}s`))
    })
  })
}

export default download

感谢安德烈·特卡琴科，我修改了他的要点

将其包含在另一个文件中并使用

const download = require('./download.js')
const url = 'https://raw.githubusercontent.com/replace-this-with-your-remote-file'
console.log('Downloading ' + url)

async function run() {
  console.log('Downloading file')
  try {
    await download(url, 'server')
    console.log('Download done')
  } catch (e) {
    console.log('Download failed')
    console.log(e.message)
  }
}

run()