How to Add Secure, Hassle-Free Authentication to Your Vue Apps with Auth0

Are you building a Vue application that requires user login and authentication? Implementing your own authentication system from scratch can be time-consuming and prone to security vulnerabilities if not done carefully. Fortunately, you can save a lot of development time and headache by integrating a trusted authentication provider like Auth0 into your Vue app.

In this in-depth guide, I‘ll walk you through the process of setting up Auth0 and adding authentication to a Vue application step-by-step. By the end, you‘ll have a fully functioning login and logout flow, with no compromise on security. Let‘s jump in!

Why Use Auth0 with Vue?

Before we get to the hands-on part, let‘s quickly review what Vue and Auth0 are and the benefits of using them together.

Vue is a popular progressive JavaScript framework for building user interfaces. Its component-based architecture and declarative rendering model make it easy to develop modern, reactive front-end applications. Vue is known for being lightweight, easy to learn, and having great performance.

Auth0 is a flexible, drop-in solution for adding authentication and authorization to applications. It provides a universal authentication and authorization platform that secures web, mobile and legacy applications. Auth0 makes it easy to implement even complex use cases and offers a wide range of features, including:

• Support for multiple authentication methods, like username/password, social providers, enterprise federation, and passwordless
• User management, with easy administrative tools and customizable user profiles
• Advanced security features like multi-factor authentication, anomaly detection, and encryption
• Extensive documentation, quickstarts, and libraries for easy integration
• Scalable, reliable cloud infrastructure with 99.99% uptime guarantees

Together, Vue and Auth0 are a perfect match for building secure single-page applications. Auth0 takes the complexity out of implementing authentication and lets you focus on your core application, while Vue makes it easy to create dynamic, engaging user experiences.

Some specific benefits of using Auth0 with Vue:

• Saves a huge amount of development time and allows you to launch faster
• Reduces security risks and liability by relying on a battle-tested, actively maintained authentication system
• Provides a more polished, professional login experience for your users out-of-the-box
• Offers pre-built components and excellent documentation for integrating with Vue
• Gives you greater flexibility to adapt to changing requirements over time

Sold on using Auth0 and ready to integrate it into your Vue app? Read on for step-by-step instructions!

Setting Up an Auth0 Account and Application

The first step is signing up for a free Auth0 account if you don‘t have one already.

1. Go to https://auth0.com/signup and create an account. You can sign up with an email/password or using your Google or Github account.

2. Once logged in, go to the Applications section of the dashboard and click "Create Application".

3. Choose a name for your application, select "Single Page Web Applications", and click Create.

4. Go to the "Settings" tab. You‘ll need to add your Vue app‘s URL to the following fields:

• Allowed Callback URLs
• Allowed Logout URLs
• Allowed Web Origins

If you‘re just testing locally, you can use http://localhost:PORT (PORT is typically 8080 for Vue apps, or whatever you have configured). In production, you‘ll need to update these with your deployed app‘s URL.

5. While you‘re in Settings, make note of your Domain and Client ID values. You‘ll use these to configure the Auth0 SDK in your Vue app.

6. Scroll down and click "Save Changes". Your Auth0 application is now set up and ready to be integrated with Vue.

Creating a Vue Application

If you don‘t already have a Vue app, let‘s quickly scaffold a new one using the Vue CLI. Make sure you have Node.js and npm installed first.

1. Install the Vue CLI globally:

npm install -g @vue/cli

2. Create a new Vue project:

vue create my-app

Choose "Manually select features" and be sure to select "Router" if you want to use Vue Router for navigation. I also recommend using "Babel" and "Linter / Formatter" for a better development experience.

3. Change into your new app directory and run the development server:

cd my-app
npm run serve

4. Open http://localhost:8080 and ensure your default Vue app loads. With the skeleton app working, we‘re ready to integrate Auth0!

Integrating Auth0 into Your Vue Application

Now for the fun part – actually adding Auth0 authentication to the Vue app. We‘ll use the official auth0-spa-js library to make this as painless as possible.

1. Install the auth0-spa-js library using npm:

npm install @auth0/auth0-spa-js

2. Create an authentication service to handle all of the Auth0 interaction. Create a new file src/auth/index.js and add the following code:

import createAuth0Client from ‘@auth0/auth0-spa-js‘;
import { computed, reactive, onMounted, watchEffect } from ‘vue‘;

let client;
const state = reactive({
  loading: true,
  isAuthenticated: false,
  user: {},
  popupOpen: false,
  error: null,
});

async function loginWithPopup() {
  state.popupOpen = true;

  try {
    await client.loginWithPopup();
  } catch (e) {
    console.error(e);
  } finally {
    state.popupOpen = false;
  }

  state.user = await client.getUser();
  state.isAuthenticated = true;
}

async function handleRedirectCallback() {
  state.loading = true;

  try {
    await client.handleRedirectCallback();
    state.user = await client.getUser();
    state.isAuthenticated = true;
  } catch (e) {
    state.error = e;
  } finally {
    state.loading = false;
  }
}

function loginWithRedirect(o) {
  return client.loginWithRedirect(o);
}

function getIdTokenClaims(o) {
  return client.getIdTokenClaims(o);
}

function getTokenSilently(o) {
  return client.getTokenSilently(o);
}

function getTokenWithPopup(o) {
  return client.getTokenWithPopup(o);
}

function logout(o) {
  return client.logout(o);
}

const authPlugin = {
  isAuthenticated: computed(() => state.isAuthenticated),
  loading: computed(() => state.loading),
  user: computed(() => state.user),
  getIdTokenClaims,
  getTokenSilently,
  getTokenWithPopup,
  handleRedirectCallback,
  loginWithRedirect,
  loginWithPopup,
  logout,
};

async function init(options) {
  client = await createAuth0Client({
    ...options,
  });

  try {
    // If the user is returning to the app after authentication
    if (
      window.location.search.includes(‘code=‘) &&
      window.location.search.includes(‘state=‘)
    ) {
      // handle the redirect and retrieve tokens
      const { appState } = await client.handleRedirectCallback();

      // Notify subscribers that the redirect callback has happened
      state.error = null;
    }
  } catch (e) {
    state.error = e;
  } finally {
    // Initialize app state
    state.isAuthenticated = await client.isAuthenticated();
    state.user = await client.getUser();
    state.loading = false;
  }

  return {
    install: (app) => {
      app.provide(‘Auth‘, authPlugin);
    },
  };
}

export default init;

This service uses the Auth0 SDK to provide methods for logging in, logging out, and getting user info and tokens. It exposes this functionality to your Vue components via a plugin.

3. Configure the Auth0 plugin. Create a new file auth_config.js in your project root:

export const domain = "<YOUR AUTH0 DOMAIN>";
export const clientId = "<YOUR AUTH0 CLIENT ID>";

Replace <YOUR AUTH0 DOMAIN> and <YOUR AUTH0 CLIENT ID> with the values from your Auth0 application settings.

Then update src/main.js to import and use the plugin:

import { createApp } from ‘vue‘;
import App from ‘./App.vue‘;
import router from ‘./router‘;
import Auth from ‘./auth‘;
import { domain, clientId } from ‘../auth_config‘;

const app = createApp(App);

app.use(Auth, {
  domain,
  clientId,
  redirect_uri: window.location.origin,
});

app.use(router);

app.mount(‘#app‘);

4. Add login and logout buttons. Open up src/App.vue and add the following to the template section:

<template>
  <div id="nav">
    <router-link to="/">Home</router-link> |
    <router-link v-if="isAuthenticated" to="/profile">Profile</router-link> |
    <button v-if="!isAuthenticated" @click="login">Log in</button>
    <button v-if="isAuthenticated" @click="logout">Log out</button>
  </div>
  <router-view />
</template>

And add the following to the script section:

<script>
export default {
  inject: [‘Auth‘],
  computed: {
    isAuthenticated() {
      return this.Auth.isAuthenticated;
    },
  },
  methods: {
    login() {
      this.Auth.loginWithRedirect();
    },
    logout() {
      this.Auth.logout();
    },
  }
}
</script>

Now you should see a login button if the user is logged out and a logout button if they are logged in. Clicking login will take you to Auth0‘s Universal Login page to enter credentials.

5. Protect routes. If you want to restrict certain routes to only authenticated users, you can do so using Vue Router‘s navigation guards.

// router/index.js
import { createRouter, createWebHistory } from ‘vue-router‘;

const routes = [
  {
    path: ‘/‘,
    name: ‘Home‘,
    component: Home,
  },
  {
    path: ‘/profile‘,
    name: ‘Profile‘,
    component: Profile,
    meta: {
      requiresAuth: true,
    },
  },
];

const router = createRouter({
  history: createWebHistory(process.env.BASE_URL),
  routes,
});

// Navigation guard
router.beforeEach((to, from, next) => {
  const { isAuthenticated } = router.app.$auth;
  if (to.meta.requiresAuth && !isAuthenticated.value) {
    return next(‘/‘);
  }
  return next();
});

export default router;

6. Access ID token. Once the user is authenticated, you will likely need to access their ID token to call protected API endpoints. Here‘s an example of how you could retrieve it before making an API call:

try {
  const token = await this.Auth.getTokenSilently();
  const response = await fetch(‘/api/protected-route‘, {
    headers: {
      Authorization: `Bearer ${token}`,
    },
  });
  const data = await response.json();
  // Do something with data
} catch (e) {
  // Handle errors
}

Testing and Debugging Authentication

As you implement authentication, it‘s important to test different scenarios to ensure your application behaves as expected. Here are some key flows to test:

• Logging in with valid and invalid credentials
• Signing up as a new user
• Accessing protected routes while authenticated and unauthenticated
• Refreshing tokens and ensuring sessions persist
• Logging out and ensuring the auth state updates across the app

Auth0 provides detailed logs which can help you debug any issues. Check the "Logs" section of the Auth0 dashboard to see events like successful and failed logins, signups, etc.

You can also use Vue Devtools to inspect the authentication state of your application in real-time as you test different scenarios.

Additional Auth0 Features to Explore

This guide covered the basics of implementing authentication in a Vue app with Auth0. But Auth0 offers many more features that could enhance your application. Here are a few to consider as you build out your app:

• Social login – Allow users to authenticate with Google, Facebook, Twitter, Github, and more
• Multi-factor authentication – Enhance security by requiring additional factors like SMS or push notification during login
• User management – Easily manage user profiles, metadata, and roles from the Auth0 dashboard
• Single sign-on – Enable users to authenticate once and access multiple applications
• Passwordless authentication – Let users log in with just an email link or one-time code

Integrating these features is out of scope for this guide, but Auth0 provides excellent documentation and guides for each use case. Definitely check out their docs for more inspiration!

Conclusion

We covered a lot of ground in this guide! You learned why you might want to use Auth0 for authentication in a Vue app, how to configure Auth0 and integrate it with a new or existing Vue app, and best practices for managing the authentication state and flow.

Auth0 really does make authentication in Vue a breeze compared to implementing it from scratch. By leveraging their battle-tested platform and excellent documentation and SDKs, you can focus on building your core application and leave the complexities of authentication to the experts.

I hope this in-depth tutorial gave you the knowledge and inspiration to add Auth0 to your own Vue projects. To dive even deeper, check out these additional resources:

• The official Auth0 Vue Quickstart: https://auth0.com/docs/quickstart/spa/vuejs
• Auth0 Vue SDK Documentation: https://auth0.github.io/auth0-vue/
• More Vue tutorials and guides: https://vuejs.org/resources/themes.html

Happy coding, and feel free to reach out if you have any questions! You can find more of my writing and projects at mywebsite.com.