Next.js

In this guide you will learn how to use the hanko-elements web components to add authentication and a user profile to your Next.js application.

Install dependencies

Install the @teamhanko/hanko-elements package:

npm

npm install @teamhanko/hanko-elements

Yarn

yarn add @teamhanko/hanko-elements

Add <hanko-auth> component

To provide a login interface in your app, use the <hanko-auth> web component. To do so, first import the register function from @teamhanko/hanko-elements in your Next.js component. Then call register to register the <hanko-auth> element with the browser's CustomElementRegistry and use the <hanko-auth> element in your JSX.

info

When adding the <hanko-auth> element to your JSX you must provide the URL of the Hanko API via the api attribute. If you are using Hanko Cloud, you can find the API URL on your project dashboard. If you are self-hosting you need to provide the URL of your running Hanko backend.

HankoAuth.jsx

import { register } from "@teamhanko/hanko-elements";

const hankoApi = "<YOUR_API_URL>";

export default function HankoAuth() {
  useEffect(() => {
    // register the component
    // see: https://github.com/teamhanko/hanko/blob/main/frontend/elements/README.md#script
    register({ shadow: true })
      .catch((error) => {
        // handle error
      });
  }, []);

  return (
    <hanko-auth api={hankoApi} />
  );
}

The call to register attempts to register the <hanko-auth> element with the browser's CustomElementRegistry through a call to window.customElements.define(). Next.js pre-renders pages on the server but the browser window is not available during pre-rendering, so the custom element registration would fail.

A solution for this is to use Next's dynamic import feature to dynamically load the component on the client-side and disable server rendering for it:

index.js

import dynamic from "next/dynamic";

export default function Home() {
  const HankoAuth = dynamic(
    // replace with path to your component using the <hanko-auth> element
    () => import('../components/HankoAuth'),
    { ssr: false },
  )
  return (
    <Suspense fallback={"Loading ..."}>
      <HankoAuth/>
    </Suspense>
  )
}

Define login callbacks

The <hanko-auth> element dispatches a custom hankoAuthSuccess event on successful login. React to this event in order to, for example, redirect your users to protected pages in your application, e.g. a user profile page.

To do so, apply an event listener with an appropriate redirect callback:

HankoAuth.jsx

import React, { useEffect, useCallback } from "react";
import { useRouter } from "next/router";
import { register } from "@teamhanko/hanko-elements";

const hankoApi = "<YOUR_API_URL>";

export default function HankoAuth() {
  const router = useRouter();

  const redirectAfterLogin = useCallback(() => {
    // successfully logged in, redirect to a page in your application
    router.replace("...");
  }, [router]);

  useEffect(() => {
    document.addEventListener("hankoAuthSuccess", redirectAfterLogin);
    return () =>
      document.removeEventListener("hankoAuthSuccess", redirectAfterLogin);
  }, [redirectAfterLogin]);

  useEffect(() => {
    // register the component
    // see: https://github.com/teamhanko/hanko/blob/main/frontend/elements/README.md#script
    register({ shadow: true })
      .catch((error) => {
        // handle error
      });
  }, []);

  return (
    <hanko-auth api={hankoApi} />
  );
}

Add <hanko-profile> component

To provide a page where users can manage their email addresses, password and passkeys, use the <hanko-profile> web component. Just as with the <hanko-auth> component, import the register function from @teamhanko/hanko-elements in your Next.js component. Then call register to register the <hanko-profile> element with the browser's CustomElementRegistry and use the element in your JSX.

info

When adding the <hanko-profile> element to your template you must provide the URL of the Hanko API via the api attribute. If you are using Hanko Cloud, you can find the API URL on your project dashboard. If you are self-hosting you need to provide the URL of your running Hanko backend.

HankoProfile.jsx

import { useEffect } from "react";
import { register } from "@teamhanko/hanko-elements";

const hankoApi = "<YOUR_API_URL>";

export default function HankoProfile() {
  useEffect(() => {
    // register the component
    // see: https://github.com/teamhanko/hanko/blob/main/frontend/elements/README.md#script
    register({ shadow: true })
      .catch((error) => {
        // handle error
      });
  }, []);

  return (
    <hanko-profile api={hankoApi} />
  );
};

Customize component styles

The styles of the hanko-auth and hanko-profile elements can be customized using CSS variables and parts. See our guide on customization here.

Authenticate backend requests

If you want to authenticate requests in your own backend, please view our backend guide.