Solving the Mystery of Missing Cookies in Next.js 14: A Step-by-Step Guide

Are you frustrated with cookies not being set in your Next.js 14 application, despite deploying it on Vercel and using an Express API? You’re not alone! In this article, we’ll dive into the world of cookies and explore the reasons behind this issue. We’ll also provide a comprehensive, step-by-step guide to help you troubleshoot and resolve this problem.

Understanding Cookies in Next.js 14

In Next.js 14, cookies are an essential part of authenticating and authorizing users. When a user requests a page, the server sends a response that includes a Set-Cookie header, which sets a cookie in the user’s browser. This cookie is then sent back to the server with each subsequent request, allowing the server to identify the user and provide personalized content.

However, with the introduction of Next.js 14, the way cookies are handled has changed. In this version, Next.js uses the getServerSideProps method to pre-render pages on the server. This means that cookies are no longer set automatically by the server.

The Problem: Cookies are not being set

When you deploy your Next.js 14 application on Vercel and use an Express API, you might encounter an issue where cookies are not being set in the browser. This can lead to authentication and authorization problems, causing users to be logged out or unable to access protected content.

The main reason for this issue is that Vercel, by default, doesn’t allow cookies to be set from the server-side. This is a security feature to prevent attacks from malicious servers. However, this also means that your Next.js 14 application can’t set cookies by default.

Solution 1: Enabling Cookies in Vercel

The first step to resolving this issue is to enable cookies in Vercel. You can do this by adding a configuration file to your project.

// vercel.json
{
  "version": 2,
  "headers": [
    {
      "source": "/api/(.*)",
      "headers": [{"key": "Set-Cookie", "value": "(.*)"}]
    }
  ]
}

This configuration file tells Vercel to allow cookies to be set from the server-side for API routes.

Solution 2: Setting Cookies in Express API

Once you’ve enabled cookies in Vercel, you need to set cookies in your Express API. You can do this by using the res.cookie() method in your API routes.

// api/cookies.js
import express from 'express';
const app = express();

app.get('/set-cookie', (req, res) => {
  res.cookie('token', 'my-secret-token', {
    httpOnly: true,
    secure: true,
    sameSite: 'strict',
  });
  res.status(200).send('Cookie set!');
});

In this example, we’re setting a cookie named token with the value my-secret-token. We’re also setting the httpOnly, secure, and sameSite options to ensure the cookie is secure and only accessible from the server-side.

Solution 3: Using getServerSideProps with Cookies

In Next.js 14, you need to use the getServerSideProps method to pre-render pages on the server. When using this method, you need to set cookies manually using the res.cookie() method.

// pages/_app.js
import { GetServerSideProps } from 'next';
import cookies from 'next/cookies';

export const getServerSideProps = async ({ req, res }) => {
  const token = 'my-secret-token';
  res.cookie('token', token, {
    httpOnly: true,
    secure: true,
    sameSite: 'strict',
  });
  return { props: {} };
};

In this example, we’re setting the token cookie using the res.cookie() method in the getServerSideProps method.

Solution 4: Using a Custom Hook for Cookies

If you want to set cookies in a more elegant way, you can create a custom hook that wraps the res.cookie() method.

// hooks/useCookies.js
import { useState, useEffect } from 'react';
import cookies from 'next/cookies';

const useCookies = (cookieName, defaultValue) => {
  const [cookie, setCookie] = useState(defaultValue);

  useEffect(() => {
    const { req, res } = cookies();
    if (!cookie) {
      res.cookie(cookieName, defaultValue, {
        httpOnly: true,
        secure: true,
        sameSite: 'strict',
      });
    }
  }, [cookie, cookieName, defaultValue]);

  return [cookie, setCookie];
};

export default useCookies;

This custom hook provides a convenient way to set and get cookies in your Next.js 14 application.

Conclusion

Cookies are an essential part of modern web applications, and setting them correctly is crucial for authentication and authorization. By following the steps outlined in this article, you should be able to resolve the issue of cookies not being set in your Next.js 14 application deployed on Vercel and using an Express API.

Remember to enable cookies in Vercel, set cookies in your Express API using the res.cookie() method, use the getServerSideProps method with cookies, and consider using a custom hook for cookies. With these solutions, you’ll be able to authenticate and authorize users securely and efficiently.

Troubleshooting Tips

If you’re still experiencing issues with cookies not being set, here are some troubleshooting tips to keep in mind:

• Make sure you’ve enabled cookies in Vercel and set the correct configuration.
• Verify that you’re setting cookies correctly in your Express API using the res.cookie() method.
• Check that you’re using the correct domain and path for your cookies.
• Ensure that you’re not overriding the Set-Cookie header in your Vercel configuration or Express API.
• Inspect the request and response headers in your browser’s developer tools to ensure that cookies are being sent correctly.

Solution	Description
Enable Cookies in Vercel	Configure Vercel to allow cookies to be set from the server-side.
Set Cookies in Express API	Use the res.cookie() method to set cookies in your Express API.
Use getServerSideProps with Cookies	Set cookies manually using the res.cookie() method in the getServerSideProps method.
Use a Custom Hook for Cookies	Create a custom hook that wraps the res.cookie() method for a more elegant way to set cookies.

By following these solutions and troubleshooting tips, you should be able to resolve the issue of cookies not being set in your Next.js 14 application deployed on Vercel and using an Express API.Here are 5 Questions and Answers about “Cookies are not being set in Nextjs 14 from Express Api Deployed on Vercel” in a creative voice and tone:

Frequently Asked Question

Got stuck with cookies not being set in your Nextjs 14 application using Express API deployed on Vercel? Don’t worry, we’ve got you covered!