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 Line sign-in experience (user authentication) with Ruby and Logto.

Prerequisites

• A running Logto instance. Check out the introduction page to get started.
• Basic knowledge of Ruby.
• A usable Line 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 Traditional web application, simply follow these steps:

1. 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.
2. In the opening modal, click the "Traditional web" section or filter all the available "Traditional web" frameworks using the quick filter checkboxes on the left. Click the "Ruby" framework card to start creating your application.
3. 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 Ruby with Logto

ヒント:

• The following demonstration is built on Ruby 3.3.3.
• The sample project is available in the GitHub repository.

Installation

Install Logto SDK via bundler:

bundle add logto

Or whatever your preferred method of adding gems is.

注記:

The following demonstration is for Ruby on Rails. However, you can apply the same steps to other Ruby frameworks.

Initialize Logto client

In the file where you want to initialize the Logto client (e.g. a base controller or a middleware), add the following code:

require "logto/client"

@client = LogtoClient.new(
  config: LogtoClient::Config.new(
    endpoint: "https://your-logto-endpoint.com",
    app_id: "your-logto-app-id",
    app_secret: "your-logto-app-secret"
  ),
  navigate: ->(uri) { a_redirect_method(uri) },
  storage: LogtoClient::SessionStorage.new(the_session_object)
)
end

For instance, in a Rails controller, the code might look like this:

app/controllers/sample_controller.rb

require "logto/client"

class SampleController < ApplicationController
  before_action :initialize_logto_client

  private

  def initialize_logto_client
    @client = LogtoClient.new(
      config: LogtoClient::Config.new(
        # ...your configuration
      ),
      # Allow the client to redirect to other hosts (i.e. your Logto tenant)
      navigate: ->(uri) { redirect_to(uri, allow_other_host: true) },
      # Controller has access to the session object
      storage: LogtoClient::SessionStorage.new(session)
    )
  end
end

Configure redirect URIs

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:

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

Regarding redirect-based sign-in

1. This authentication process follows the OpenID Connect (OIDC) protocol, and Logto enforces strict security measures to protect user sign-in.
2. 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.

---

注記:

In the following code snippets, we assume your app is running on http://localhost:3000/.

Configure redirect URIs

Switch to the application details page of Logto Console. Add a redirect URI http://localhost:3000/callback.

Just like signing in, users should be redirected to Logto for signing out of the shared session. Once finished, it would be great to redirect the user back to your website. For example, add http://localhost:3000/ as the post sign-out redirect URI section.

Then click "Save" to save the changes.

Handle the callback

Since the redirect URI has been set to http://localhost:3000/callback, it needs to be handled it in our application. In a Rails controller, you can add the following code:

app/controllers/sample_controller.rb

class SampleController < ApplicationController
  def callback
    @client.handle_sign_in_callback(url: request.original_url)
  end
end

And configure the route in config/routes.rb:

config/routes.rb

Rails.application.routes.draw do
  get "/callback", to: "sample#callback"
end

Invoke sign-in and sign-out

There are various ways to invoke sign-in and sign-out in your application. For example, you can implement two routes in your Rails application:

app/controllers/sample_controller.rb

class SampleController < ApplicationController
  def sign_in
    @client.sign_in(redirect_uri: request.base_url + "/callback")
  end

  def sign_out
    @client.sign_out(post_logout_redirect_uri: request.base_url)
  end

  # ...
end

config/routes.rb

Rails.application.routes.draw do
  get "/sign_in", to: "sample#sign_in"
  get "/sign_out", to: "sample#sign_out"

  # ...
end

Then you can create buttons or links in your views to trigger these actions. For example:

app/views/sample/index.html.erb

<% if @client.is_authenticated? %>
  <a href="<%= sign_out_path %>">Sign out</a>
<% else %>
  <a href="<%= sign_in_path %>">Sign in</a>
<% end %>

Checkpoint: Test your application

Now, you can test your application:

1. Run your application, you will see the sign-in button.
2. Click the sign-in button, the SDK will init the sign-in process and redirect you to the Logto sign-in page.
3. After you signed in, you will be redirected back to your application and see the sign-out button.
4. Click the sign-out button to clear token storage and sign out.

Add Line connector

To enable quick sign-in and improve user conversion, connect with Ruby 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:

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

注記:

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

Set up Line OAuth app

Setup a Line channel

Go to the Line Developers and sign in with your Line business account. If you don’t have an account, you can register for one.

Then, go to this link to create a channel.

Step 1: Fill in the Channel Details.

Complete the form and create the channel.

Step 2: Setup callback URLs.

Go to channel details page and find "LINE login" tab and edit the "Callback URL" field.

In our case, this will be ${your_logto_endpoint}/callback/${connector_id}. e.g. https://foo.logto.app/callback/${connector_id}. The connector_id can be found on the top bar of the Logto Admin Console connector details page.

Configure your connector

In your Logto connector configuration, fill out the following fields with the values obtained from your App's "Auth" tab, "Application credentials" section:

• clientId: Your App's Channel ID.
• clientSecret: Your App's Channel Secret.

scope is a space-delimited list of OIDC scopes. If not provided, the default scope is openid profile.

Config types

Name	Type
clientId	string
clientSecret	string
scope	string

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 Line connector should be available now.

Enable Line connector in Sign-in Experience

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

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

Testing and Validation

Return to your Ruby app. You should now be able to sign in with Line. Enjoy!

Further readings

End-user flows: Logto provides a out-of-the-box authentication flows including MFA and enterprise SSO, along with powerful APIs for flexible implementation of account settings, security verification, and multi-tenant experience.

Authorization: Authorization defines the actions a user can do or resources they can access after being authenticated. Explore how to protect your API for native and single-page applications and implement Role-based Access Control (RBAC).

Organizations: Particularly effective in multi-tenant SaaS and B2B apps, the organization feature enable tenant creation, member management, organization-level RBAC, and just-in-time-provisioning.

Customer IAM series Our serial blog posts about Customer (or Consumer) Identity and Access Management, from 101 to advanced topics and beyond.