Working With Cookies in Popular Web Frameworks

Cookies are a primary mechanism for maintaining state and identifying users in web applications. Being able to set, unset and check for cookies is an essential skill for web developers. In this article we'll cover how to set and unset cookies using PHP, Node.js, Laravel, Express and Flask.

In web frameworks and languages, there are functions or methods to set a cookie with an expiration time. This stores the cookie data in the user's browser.

<?php

setcookie(
    "cookie_name", 
    "cookie_value", 
    time() + 86400 // expires in 1 day
);  

?>
<?php

Cookie::queue(
    'cookie_name', 
    'cookie_value', 
    $minutes
);

// OR

request()->cookie(
    'cookie_name', 
    'cookie_value', 
    $minutes
);

?>
var express = require('express');
var cookieParser = require('cookie-parser');

app.use(cookieParser());
var app = express();

app.get('/', function(req, res){
    res.cookie(
        "cookie_name", 
        "cookie_value", 
        { maxAge: 86400000 } // 1 day
    ).send('');
 });

response.set_cookie(
    "cookie_name", 
    "cookie_value", 
    max_age=86400 # 1 day
)

Get all cookies

<?php

print_r($_COOKIE);

?>
<?php

request()->cookie(); 

?>
console.log('Cookies: ', req.cookies);
request.cookies

<?php

$_COOKIE['cookie_name'];

?>
<?php

request()->cookie('cookie_name'); 

?>
req.cookies['cookie_name'];
request.cookies.get('cookie_name')

To unset a cookie, we simply set it again but with an expiration time in the past. This instructs the browser to delete that cookie.

<?php

setcookie(
    "cookie_name", 
    "", 
    time() - 3600 // expires 1 hour ago
);  

// OR 

setcookie('cookie_name');

// OR 

unset($_COOKIE['cookie_name']);

?>
<?php

Cookie::queue(
    'cookie_name', 
    'null', 
    $minutes
);

?>
res.clearCookie('cookie_name');
response.set_cookie(
    "cookie_name", 
    "", 
    max_age=0
)


More Readings!