How to use cookie inside `getServerSideProps` method in Next.js?

Question

I have to send current language on endpoint. But getting language from Cookie returns undefined inside getServerSideProps.

export async function getServerSideProps(context) {
    const lang = await Cookie.get('next-i18next')
    const res = await fetch(`endpoint/${lang}`)
    const data = await res.json()

    return {
        props: { data },
    }
}

export default Index;

What is the proper way to get cookie inside getServerSideProps?

Answer 1

You can get the cookies from the req.headers inside getServerSideProps:

export async function getServerSideProps(context) {
  const cookies = context.req.headers.cookie;
  return {
    props: {},
  };
}

You could then use the cookie npm package to parse them:

import * as cookie from 'cookie'

export async function getServerSideProps(context) {
  const parsedCookies = cookie.parse(context.req.headers.cookie);
  return { props: {} }
}