How to build Discord sign-in with Capacitor JS

For our new friends:

Logto is an Auth0 alternative designed for modern apps and SaaS products. It offers both Cloud and Open-source services to help you quickly launch your identity and management (IAM) system. Enjoy authentication, authorization, and multi-tenant management all in one.

We recommend starting with a free development tenant on Logto Cloud. This allows you to explore all the features easily.

In this article, we will go through the steps to quickly build the Discord sign-in experience (user authentication) with Capacitor JS and Logto.

Prerequisites

A running Logto instance. Check out the introduction page to get started.
Basic knowledge of Capacitor JS.
A usable Discord account.

Create an application in Logto

Logto is based on OpenID Connect (OIDC) authentication and OAuth 2.0 authorization. It supports federated identity management across multiple applications, commonly called Single Sign-On (SSO).

To create your Native app application, simply follow these steps:

Open the Logto Console. In the "Get started" section, click the "View all" link to open the application frameworks list. Alternatively, you can navigate to Logto Console > Applications, and click the "Create application" button.
In the opening modal, click the "Native app" section or filter all the available "Native app" frameworks using the quick filter checkboxes on the left. Click the "Capacitor JS" framework card to start creating your application.
Enter the application name, e.g., "Bookstore," and click "Create application".

🎉 Ta-da! You just created your first application in Logto. You'll see a congrats page which includes a detailed integration guide. Follow the guide to see what the experience will be in your application.

Integrate Capacitor JS with Logto

astuce:

The following demonstration is built on Capacitor JS 5.0.6.

Installation

Install Logto SDK and peer dependencies via your favorite package manager:

npm
Yarn
pnpm

npm i @logto/capacitor
npm i @capacitor/browser @capacitor/app @capacitor/preferences

yarn add @logto/capacitor
yarn add @capacitor/browser @capacitor/app @capacitor/preferences

pnpm add @logto/capacitor
pnpm add @capacitor/browser @capacitor/app @capacitor/preferences

The @logto/capacitor package is the SDK for Logto. The remaining packages are its peer dependencies.

Init Logto client

Add the following code to your Capacitor project:

import LogtoClient, { type LogtoConfig } from '@logto/capacitor';

const logtoConfig: LogtoConfig = {
  endpoint: '<your-logto-endpoint>',
  appId: '<your-application-id>',
};

const logtoClient = new LogtoClient(config);

Before we dive into the details, here's a quick overview of the end-user experience. The sign-in process can be simplified as follows:

Your app invokes the sign-in method.
The user is redirected to the Logto sign-in page. For native apps, the system browser is opened.
The user signs in and is redirected back to your app (configured as the redirect URI).

This authentication process follows the OpenID Connect (OIDC) protocol, and Logto enforces strict security measures to protect user sign-in.
If you have multiple apps, you can use the same identity provider (Logto). Once the user signs in to one app, Logto will automatically complete the sign-in process when the user accesses another app.

To learn more about the rationale and benefits of redirect-based sign-in, see Logto sign-in experience explained.

Now, let's configure the redirect URI. The redirect URI is used to redirect the user back to your application after the authentication flow.

Ensure that the URI redirects to the Capacitor app, for example, com.example.app://callback. The value may vary depending on your Capacitor app configuration. For more details, see Capacitor Deep Links.

Then, add the following code to the onClick handler of the sign-in button:

const onClick = async () => {
  await logtoClient.signIn('com.example.app://callback');
  console.log(await logtoClient.isAuthenticated()); // true
  console.log(await logtoClient.getIdTokenClaims()); // { sub: '...', ... }
};

Implement sign-out

Since Capacitor leverages the Safari View Controller on iOS and Chrome Custom Tabs on Android, the authentication state can be persisted for a while. However, sometimes the user may want to sign out of the application immediately. In this case, we can use the signOut method to sign out the user:

const onClick = async () => {
  await logtoClient.signOut();
  console.log(await logtoClient.isAuthenticated()); // false
};

The signOut method has an optional parameter for the post sign-out redirect URI. If it's not provided, the user will be redirected to the Logto sign-out page.

The user needs to click "Done" to close the web view and return to the Capacitor app. If you want to automatically redirect the user back to the Capacitor app, you can provide the post sign-out redirect URI, for instance, com.example.app://callback/sign-out.

Ensure that the post sign-out redirect URI can redirect to the Capacitor app. Then add the following code to the onClick handler of the sign-out button:

const onClick = async () => {
  await logtoClient.signOut('com.example.app://callback/sign-out');
};

Checkpoint: Trigger the authentication flow

Run the Capacitor app and click the sign-in button. A browser window will open, redirecting to the Logto sign-in page.

If the user closes the browser window without completing the authentication flow, the Capacitor app will receive a LogtoClientError.

Add Discord connector

To enable quick sign-in and improve user conversion, connect with Capacitor JS as an identity provider. The Logto social connector helps you establish this connection in minutes by allowing several parameter inputs.

To add a social connector, simply follow these steps:

Navigate to Console > Connectors > Social Connectors.
Click "Add social connector" and select "Discord".
Follow the README guide and complete required fields and customize settings.

remarque:

If you are following the in-place Connector guide, you can skip the next section.

Set up Discord OAuth app

Register a developer application

Visit Discord Developer Portal and sign in with your Discord account.
Click the New Application button to create an application, choose a name for it (Ex: LogtoAuth), tick the box and click Create.
Go to OAuth2 page and click Reset Secret
Take note of the CLIENT ID and CLIENT SECRET fields
Add the valid redirects (Ex: http://auth.mycompany.io/callback/${connector_id}). The connector_id can be found on the top bar of the Logto Admin Console connector details page.

Configure Logto

Config types

Name	Type
clientId	string
clientSecret	string
scope	string

clientId

clientId is the CLIENT ID field we saved earlier. (You can find it in the Oauth2 Page in Discord Developer Portal.)

clientSecret

clientSecret is the CLIENT SECRET we saved earlier. (If you've lost it you need to click Reset Secret.)

scope

scope is the permissions granted by the user's authorization. The default value is identify email. You can see the full list of scopes here.

Save your configuration

Double check you have filled out necessary values in the Logto connector configuration area. Click "Save and Done" (or "Save changes") and the Discord connector should be available now.

Once you create a social connector successfully, you can enable it as a "Continue with Discord" button in Sign-in Experience.

Navigate to Console > Sign-in experience > Sign-up and sign-in.
(Optional) Choose "Not applicable" for sign-up identifier if you need social login only.
Add configured Discord connector to the "Social sign-in" section.

Testing and Validation

Return to your Capacitor JS app. You should now be able to sign in with Discord. Enjoy!

Create an application in Logto​

Integrate Capacitor JS with Logto​

Installation​

Init Logto client​

Implement sign-in​

Regarding redirect-based sign-in​

Implement sign-out​

Checkpoint: Trigger the authentication flow​

Add Discord connector​

Set up Discord OAuth app​

Register a developer application​

Configure Logto​

Config types​

clientId​

clientSecret​

scope​

Save your configuration​

Enable Discord connector in Sign-in Experience​

Testing and Validation​

Further readings​