javascript - Download a file using Nightmare - Stack Overflow

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I am using Nightmare to create a automated downloader for today's newspaper. I managed to login and go the the specified page. However I could not find out how to download a file with Nightmare.

var Nightmare = require('nightmare');
new Nightmare()
  .goto('://digitaleeditie.nrc.nl/welkom')
    .type('input[name="username"]', 'Username')
    .type('input[name="password"]','Password')
    .click('button[type="submit"]')
    .wait()
    .goto('.html')
    .wait()
    .click('a[href="/digitaleeditie/helekrant/epub/nrc_20141124.epub"]')
    .wait()

    .url(function(url) {
        console.log(url)
    })
    .run(function (err, nightmare) {
      if (err) return console.log(err);
      console.log('Done!');
    });

I tried to download the file by clicking on the download button. However this seems not to work.

I am using Nightmare to create a automated downloader for today's newspaper. I managed to login and go the the specified page. However I could not find out how to download a file with Nightmare.

var Nightmare = require('nightmare');
new Nightmare()
  .goto('https://login.nrc.nl/login?service=http://digitaleeditie.nrc.nl/welkom')
    .type('input[name="username"]', 'Username')
    .type('input[name="password"]','Password')
    .click('button[type="submit"]')
    .wait()
    .goto('http://digitaleeditie.nrc.nl/digitaleeditie/NH/2014/10/20141124___/downloads.html')
    .wait()
    .click('a[href="/digitaleeditie/helekrant/epub/nrc_20141124.epub"]')
    .wait()

    .url(function(url) {
        console.log(url)
    })
    .run(function (err, nightmare) {
      if (err) return console.log(err);
      console.log('Done!');
    });

I tried to download the file by clicking on the download button. However this seems not to work.

• javascript
• download
• phantomjs
• nightmare

Share Improve this question Follow edited Nov 24, 2014 at 21:23 Artjom B. 61.9k2525 gold badges134134 silver badges229229 bronze badges asked Nov 24, 2014 at 16:32 Fokke DekkerFokke Dekker 12611 silver badge66 bronze badges

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4 Answers 4

Sorted by: Reset to default 5

PhantomJS (and CasperJS and Nightmare) don't trigger a download (dialog) when you click on something that should be downloaded. So, it is necessary to download it yourself. If you can find out the URL of the file, then it can be easily downloaded using an XMLHttpRequest from the page context.

So you need to exchange

.click('a[href="/digitaleeditie/helekrant/epub/nrc_20141124.epub"]')

for

.evaluate(function ev(){
    var el = document.querySelector("[href*='nrc_20141124.epub']");
    var xhr = new XMLHttpRequest();
    xhr.open("GET", el.href, false);
    xhr.overrideMimeType("text/plain; charset=x-user-defined");
    xhr.send();
    return xhr.responseText;
}, function cb(data){
    var fs = require("fs");
    fs.writeFileSync("book.epub", data, "binary");
})

You can also use the newer way of requesting binary data.

.evaluate(function ev(){
    var el = document.querySelector("[href*='.pdf']");
    var xhr = new XMLHttpRequest();
    xhr.open("GET", el.href, false);
    xhr.responseType = "arraybuffer";
    xhr.send();

    var bytes = [];
    var array = new Uint8Array(xhr.response);
    for (var i = 0; i < array.length; i++) {
        bytes[i] = array[i];
    }
    return bytes;
}, function cb(data){
    var fs = require("fs");
    fs.writeFileSync("book.epub", new Buffer(data), "binary");
})

Both of the ways are described on MDN. Here is a sample script which shows a proof of concept.

There is a Nightmare download plugin. You can download the file just with this code below:

var Nightmare = require('nightmare');
require('nightmare-download-manager')(Nightmare);
var nightmare = Nightmare();
nightmare.on('download', function(state, downloadItem){
  if(state == 'started'){
    nightmare.emit('download', '/some/path/file.zip', downloadItem);
  }
});

nightmare
  .downloadManager()
  .goto('https://github./segmentio/nightmare')
  .click('a[href="/segmentio/nightmare/archive/master.zip"]')
  .waitDownloadsComplete()
  .then(() => {
    console.log('done');
  });

I got my downloads super easy using the request module, as described here.

var Nightmare = require('nightmare');
var fs = require('fs');
var request = require('request');

new Nightmare()
  .goto('https://login.nrc.nl/login?service=http://digitaleeditie.nrc.nl/welkom')
  .insert('input[name="username"]', 'Username')
  .insert('input[name="password"]','Password')
  .click('button[type="submit"]')
  .wait()
  .goto('http://digitaleeditie.nrc.nl/digitaleeditie/NH/2014/10/20141124___/downloads.html')
  .wait()
  .then(function () {
    download('http://digitaleeditie.nrc.nl/digitaleeditie/helekrant/epub/nrc_20141124.epub', 'myBook.epub', function () {
      console.log('done');
    });
  })
  .catch(function (err) {
    console.log(err);
  })

function download(uri, filename, callback) {
  request.head(uri, function () {
    request(uri).pipe(fs.createWriteStream(filename)).on('close', callback);
  });
}

Run npm i request in order to use request.

Nightmare will download it properly if you click on the download link.

const Nightmare         = require('nightmare');
const show              = ( process.argv[2].includes("true") ) ? true : false;
const nightmare         = Nightmare( { show: show } );

nightmare
    .goto("https://github./segmentio/nightmare")
    .click('a[href="/segmentio/nightmare/archive/master.zip"]')
    .end(() => "Done!")
    .then((value) => console.log(value));

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