nfriedly
set-cookie-parser
ℹ️ Note for current users: I'm considering some changes for the next major version and would appreciate your feedback: https://github.com/nfriedly/set-cookie-parser/discussions/68
Parses set-cookie headers into JavaScript objects
Accepts a single set-cookie header value, an array of set-cookie header values, a Node.js response object, or a fetch() Response object that may have 0 or more set-cookie headers.
Also accepts an optional options object. Defaults:
{
decodeValues: true, // Calls decodeURIComponent on each value - default: true
map: false, // Return an object instead of an array - default: false
silent: false, // Suppress the warning that is logged when called on a request instead of a response - default: false
}Returns either an array of cookie objects or a map of name => cookie object with {map: true}. Each cookie object will have, at a minimum name and value properties, and may have additional properties depending on the set-cookie header:
name- cookie name (string)value- cookie value (string)path- URL path to limit the scope to (string or undefined)domain- domain to expand the scope to (string or undefined, may begin with "." to indicate the named domain or any subdomain of it)expires- absolute expiration date for the cookie (Date object or undefined)maxAge- relative expiration time of the cookie in seconds from when the client receives it (integer or undefined)- Note: when using with express's res.cookie() method, multiply
maxAgeby 1000 to convert to milliseconds.
- Note: when using with express's res.cookie() method, multiply
secure- indicates cookie should only be sent over HTTPs (true or undefined)httpOnly- indicates cookie should not be accessible to client-side JavaScript (true or undefined)sameSite- indicates if cookie should be included in cross-site requests (more info) (string or undefined)- Note: valid values are
"Strict","Lax", and"None", but set-cookie-parser coppies the value verbatim and does not perform any validation.
- Note: valid values are
partitioned- indicates cookie should be scoped to the combination of 3rd party domain + top page domain (more info) (true or undefined)
(The output format is loosely based on the input format of https://www.npmjs.com/package/cookie)
Install
$ npm install --save set-cookie-parserUsage
Get array of cookie objects
var http = require('http');
var setCookie = require('set-cookie-parser');
http.get('http://example.com', function(res) {
var cookies = setCookie.parse(res, {
decodeValues: true // default: true
});
cookies.forEach(console.log);
}Example output:
[
{
name: 'bam',
value: 'baz'
},
{
name: 'foo',
value: 'bar',
path: '/',
expires: new Date('Tue Jul 01 2025 06:01:11 GMT-0400 (EDT)'),
maxAge: 1000,
domain: '.example.com',
secure: true,
httpOnly: true,
sameSite: 'lax'
}
]Get map of cookie objects
var http = require('http');
var setCookie = require('set-cookie-parser');
http.get('http://example.com', function(res) {
var cookies = setCookie.parse(res, {
decodeValues: true, // default: true
map: true // default: false
});
var desiredCookie = cookies['session'];
console.log(desiredCookie);
});Example output:
{
bam: {
name: 'bam',
value: 'baz'
},
foo: {
name: 'foo',
value: 'bar',
path: '/',
expires: new Date('Tue Jul 01 2025 06:01:11 GMT-0400 (EDT)'),
maxAge: 1000,
domain: '.example.com',
secure: true,
httpOnly: true,
sameSite: 'lax'
}
}Creating a new, modified set-cookie header
This library can be used in conjunction with the cookie library to modify and replace set-cookie headers:
const libCookie = require('cookie');
const setCookie = require('set-cookie-parser');
function modifySetCookie(res){
// parse the set-cookie headers with this library
let cookies = setCookie.parse(res);
// modify the cookies here
// ...
// create new set-cookie headers using the cookie library
res.headers['set-cookie'] = cookies.map(function(cookie) {
return libCookie.serialize(cookie.name, cookie.value, cookie);
});
}See a real-world example of this in unblocker
Usage in React Native (and with some other fetch implementations)
React Native follows the Fetch spec more closely and combines all of the Set-Cookie header values into a single string.
The splitCookiesString method reverses this.
var setCookie = require('set-cookie-parser');
var response = fetch(/*...*/);
// This is mainly for React Native; Node.js does not combine set-cookie headers.
var combinedCookieHeader = response.headers.get('Set-Cookie');
var splitCookieHeaders = setCookie.splitCookiesString(combinedCookieHeader)
var cookies = setCookie.parse(splitCookieHeaders);
console.log(cookies); // should be an array of cookiesThis behavior may become a default part of parse in the next major release, but requires the extra step for now.
Note that the fetch() spec now includes a getSetCookie() method that provides un-combined Set-Cookie headers. This library will automatically use that method if it is present.
API
parse(input, [options])
Parses cookies from a string, array of strings, or a http response object.
Always returns an array, regardless of input format. (Unless the map option is set, in which case it always returns an object.)
parseString(individualSetCookieHeader, [options])
Parses a single set-cookie header value string. Options default is {decodeValues: true}. Used under-the-hood by parse().
Returns an object.
splitCookiesString(combinedSetCookieHeader)
It's uncommon, but the HTTP spec does allow for multiple of the same header to have their values combined (comma-separated) into a single header.
This method splits apart a combined header without choking on commas that appear within a cookie's value (or expiration date).
Returns an array of strings that may be passed to parse().
References
License
MIT © Nathan Friedly