Javascript to "export" all cookies?

Question

There is a cool Firefox extension which lets you export all cookies to a Netscape HTTP Cookies File, cookies.txt, which you can then use with wget (et.al.)

Here is an example cookies.txt file for the happycog.com site:

# Netscape HTTP Cookie File
# http://www.netscape.com/newsref/std/cookie_spec.html
# This is a generated file!  Do not edit.

cognition.happycog.com  FALSE   /   FALSE   1345696044  exp_last_visit  998800044
cognition.happycog.com  FALSE   /   FALSE   1345696044  exp_last_activity   1314160044

How can I build the same style "cookies export" with Javascript? Granted it would only be able to read cookies for the current domain. That would be just fine.

Additional Details:

I realize that cookies can't be exported to the file system with pure javascript. I'd be happy with them being exported to a textarea, or with document.write. I just want to know how I can get them in the same format where I can basically copy and paste them to a cookies.txt file. The challenge here is to do it with javascript, though, and not to use an addon.

Answer 1

var cookieData = document.cookie.split(';').map(function(c) {
  var i = c.indexOf('=');
  return [c.substring(0, i), c.substring(i + 1)];
});

copy(JSON.stringify(JSON.stringify(cookieData)));

This will export your cookies into an array of key/value pairs (eg. [ [key1, val1], [key2, val2], ...]), and then copy it to your clipboard. It will not retain any expiration date info because that's impossible to extract via Javascript.

---

To import the cookies back, you'd run the following code:

var cookieData = JSON.parse(/*Paste cookie data string from clipboard*/);
cookieData.forEach(function (arr) {
  document.cookie = arr[0] + '=' + arr[1];
});