Next.js: document is not defined

Question

I am trying to create a payment form where people can pay but I keep getting this error.

document is not defined

I'm using Next.js. Please see my code below:

import React from "react";
import {Elements, StripeProvider} from 'react-stripe-elements';
import CheckoutForm from '../../components/Payment/CheckoutForm';
import { useRouter } from 'next/router';


var stripe_load = () => {
    var aScript = document.createElement('script');
    aScript.type = 'text/javascript';
    aScript.src = " https://js.stripe.com/v3/";

    document.head.appendChild(aScript);
    aScript.onload = () => {

    };
};

function Payment({host}) {
    const key = host.includes('localhost') ? 'test' : 't';

    stripe_load();

    const router = useRouter();

    return (
        <div className="Payment Main">
            <StripeProvider apiKey={key}>
                <Elements>
                    <CheckoutForm planid={router.query.id}/>
                </Elements>
            </StripeProvider>
            <br/>
            <br/>
            <p>Powered by Stripe</p>
        </div>
    );
};


Payment.getInitialProps = async ctx => {
    return { host: ctx.req.headers.host }
};

export default Payment

Answer 1

I think, in server rendering mode, the document is undefined. You should be able to use it inside class lifecycle methods or useEffect

import React, {useEffect} from "react";
import {Elements, StripeProvider} from 'react-stripe-elements';
import CheckoutForm from '../../components/Payment/CheckoutForm';
import { useRouter } from 'next/router';


var stripe_load = () => {
    var aScript = document.createElement('script');
    aScript.type = 'text/javascript';
    aScript.src = " https://js.stripe.com/v3/";

    document.head.appendChild(aScript);
    aScript.onload = () => {

    };
};

function Payment({host}) {
    const key = host.includes('localhost') ? 'test' : 't';

    useEffect(() => {
      var aScript = document.createElement('script');
       aScript.type = 'text/javascript';
       aScript.src = " https://js.stripe.com/v3/";

       document.head.appendChild(aScript);
       aScript.onload = () => {

       };
    }, [])
    //stripe_load();

    const router = useRouter();

    return (
        <div className="Payment Main">
            <StripeProvider apiKey={key}>
                <Elements>
                    <CheckoutForm planid={router.query.id}/>
                </Elements>
            </StripeProvider>
            <br/>
            <br/>
            <p>Powered by Stripe</p>
        </div>
    );
};


Payment.getInitialProps = async ctx => {
    return { host: ctx.req.headers.host }
};

export default Payment

Answer 2

You need to wrap your document using validator process.browser, because this document is belong to client side, and the error occured when nextjs render in server side.

var stripe_load = () => {
    if (process.browser) {
        var aScript = document.createElement('script');
        aScript.type = 'text/javascript';
        aScript.src = " https://js.stripe.com/v3/";

        document.head.appendChild(aScript);
        aScript.onload = () => {

        };
    }
};

Answer 3

For example, when the module includes a library that only works in the browser. Some times dynamic import can solve this issue.

Take a look at the following example:

import dynamic from 'next/dynamic'

const DynamicComponentWithNoSSR = dynamic(
  () => import('../components/hello3'),
  { ssr: false }
)

function Home() {
  return (
    <div>
      <Header />
      <DynamicComponentWithNoSSR />
      <p>HOME PAGE is here!</p>
    </div>
  )
}

export default Home

Answer 4

for me, this error occurs from lots of mistakes: first, you have to use

if (typeof window !== "undefined") {

for every window. and document. and especially for localStorage. functions (my self forgot to use this if clause for localStorage.getItem and the error didn't fix)

another problem was the import of the line below which was totally wrong!:

import {router} from "next/client";