wget的Node.js执行

Question

I'm trying to download a lot of files using nodejs and the exec command, simplified like this:

var cmd = 'wget -O output.csv URL';
var child = exec(cmd, function(err) {
  console.log('DONE');
});

However, the callback is triggered before the file was actually downloaded through wget , leading to a file that contains garbage like ' 0O 6D 1n ]v # '. Shouldn't the callback be triggered once wget is done? When running the same command on the command line it takes rougly 5 seconds, since the file has several MB.

Btw: I'm not using the request module since it's slower and I ran into emitter listener issues ( EventEmitter memory leak detected. 11 listeners added ).

Thanks!

Answer 1

This will involve some debugging.

Can you please try running your script as:

var cmd = 'wget -O output.csv URL';
var child = exec(
  cmd,
  function (error, stdout, stderr) {
    console.log('stdout: ' + stdout);
    console.log('stderr: ' + stderr);
    if (error !== null) {
      console.log('exec error: ' + error);
    }
  }
);

It would be interesting to see what stdout and stderr say.

Right, you provided me your stderr which said:

http://productdata.zanox.com/exportservice/v1/rest/22791753C32335607.csv?ticket=BC4B91472561713FD43BA766542E9240AFDD01B95B123E40B2C0375E3A68C142

This URL the command line gets is missing everything after the ampersand ( & character). This indicates a problem with escaping.

To get around this try replacing \\& with \\\\\\& .