How can I replicate the functionality of a wget with node.js?

Question

Is it possible to essentially run a wget from within a node.js app? I'd like to have a script that crawls a site, and downloads a specific file, but the href of the link that goes the file changes fairly often. So, I figured the easiest way to go about doing it would be to find the href of the link, then just perform a wget on it.

Thanks!

See the node.js documentation for [`child_process.exec(cmd)`](http://nodejs.org/docs/latest/api/all.html#all_child_process_exec_command_options_callback). — maerics, Mar 02 '12 at 22:25
All current answers are too complicated. There is a simple solution with a file stream. https://stackoverflow.com/questions/11944932/how-to-download-a-file-with-node-js-without-using-third-party-libraries — Dzenly, Apr 02 '19 at 17:04

score 20 · Answer 1 · answered Mar 03 '12 at 01:09

20

For future reference though, I would recommend request, which makes it this easy to fetch that file:

var request = require("request");

request(url, function(err, res, body) {
  // Do funky stuff with body
});

answered Mar 03 '12 at 01:09

Linus Thiel

37,636
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101

score 16 · Answer 2 · answered Mar 03 '12 at 05:50

16

While it might be a little more verbose than some third-party stuff, Node's core HTTP module provides for an HTTP client you could use for this:

var http = require('http');
var options = {
    host: 'www.site2scrape.com',
    port: 80,
    path: '/page/scrape_me.html'
  };
var req = http.get(options, function(response) {
  // handle the response
  var res_data = '';
  response.on('data', function(chunk) {
    res_data += chunk;
  });
  response.on('end', function() {
    console.log(res_data);
  });
});
req.on('error', function(err) {
  console.log("Request error: " + err.message);
});

answered Mar 03 '12 at 05:50

Wes Johnson

3,023
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2

I like that this answer utilizes only the core Node library. Good work – nic Jan 08 '14 at 08:31
If you're looking for even less work, without adding a dependency, using the built-in `url` module's `parse` method will yield an object that you can use instead of building `options`. (Assuming you have a string URI already to pass to it). – Tersosauros Nov 20 '16 at 05:59

score 8 · Accepted Answer · answered Mar 02 '12 at 22:27

You can run an external command using child_processes:

http://nodejs.org/docs/latest/api/child_process.html#child_process_child_process_exec_command_options_callback

var util = require('util'),
    exec = require('child_process').exec,
    child,
    url = 'url to file';

child = exec('wget ' + url,
  function (error, stdout, stderr) {
    console.log('stdout: ' + stdout);
    console.log('stderr: ' + stderr);
    if (error !== null) {
      console.log('exec error: ' + error);
    }
});

This answers the question, but why would you do that when you can use request? — dovidweisz, May 23 '14 at 13:57

score 2 · Answer 4 · answered Feb 08 '13 at 09:38

2

You can use node-wget. Works in cases where 'wget' is not possible

answered Feb 08 '13 at 09:38

Stan Onyime

21
1

score 1 · Answer 5 · answered Mar 02 '12 at 22:27

U can just use wget.

var exec = require('child_process').exec;

child = exec("/path/to/wget http://some.domain/some.file", function (error, stdout, stderr) {
if (error !== null) {
  console.log("ERROR: " + error);
}
else {
  console.log("YEAH IT WORKED");
}
});

How can I replicate the functionality of a wget with node.js?

5 Answers5

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