set-cookie

Set a cookie using the same API on both the client and the server.
The set-cookie module exports a function, setCookie. It takes two required arguments and one optional argument:

setCookie(cookieName, cookieValue, options);

cookieName

String

The name of the cookie.

cookieValue

String

The value of the cookie.

options (optional)

Object

Options, such as path, expires, domain. Under the hood, set-cookie uses the cookie module to serialize the cookie metadata into a string. Check out that project for the full list of options.
There is also one special option, res, which must be passed in when using set-cookie from Node. It is an instance of http.ServerResponse, which can come from a simple http server or can be a Connect or Express response.

Node

In Node, you must pass res as an option in the third argument.

var setCookie = require('set-cookie');

// In, for example, an Express middleware.
app.use(function(req, res, next) {
  setCookie('myCookie', 'the value of the cookie', {
    domain: '.example.org',
    res: res
  });
  next();
});

This would set the following HTTP header:

Set-Cookie: myCookie=the%20value%20of%20the%20cookie; Domain=.example.org

Browser

You can use a tool like Browserify to package up set-cookie, which uses the CommonJS module format, for use by a browser.

var setCookie = require('set-cookie');

setCookie('myCookie', 'the value of the cookie', {
  domain: '.example.org'
});

This would mutate document.cookie behind the scenes:

document.cookie = 'myCookie=the%20value%20of%20the%20cookie; Domain=.example.org'

MIT