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 KOOK sign-in experience (user authentication) with iOS (Swift) and Logto.

Prerequisites

• A running Logto instance. Check out the introduction page to get started.
• Basic knowledge of iOS (Swift).
• A usable KOOK 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:

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 "Native app" section or filter all the available "Native app" frameworks using the quick filter checkboxes on the left. Click the "iOS (Swift)" 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 iOS (Swift) with Logto

Add Logto SDK as a dependency

Use the following URL to add Logto SDK as a dependency in Swift Package Manager.

https://github.com/logto-io/swift.git

Since Xcode 11, you can directly import a Swift package w/o any additional tool.

We do not support Carthage and CocoaPods at the time due to some technical issues.

Carthage

Carthage needs a xcodeproj file to build, but swift package generate-xcodeproj will report a failure since we are using binary targets for native social plugins. We will try to find a workaround later.

CocoaPods

CocoaPods does not support local dependency and monorepo, thus it's hard to create a .podspec for this repo.

Init LogtoClient

Initialize the client by creating a LogtoClient instance with a LogtoConfig object.

ContentView.swift

import Logto
import LogtoClient

let config = try? LogtoConfig(
  endpoint: "<your-logto-endpoint>", // E.g. http://localhost:3001
  appId: "<your-app-id>"
)
let client = LogtoClient(useConfig: config)

info:

By default, we store credentials like ID Token and Refresh Token in the Keychain. Thus the user doesn't need to sign in again when he returns.

To turn off this behavior, set usingPersistStorage to false:

let config = try? LogtoConfig(
  // ...
  usingPersistStorage: false
)

Sign in

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.

---

Configure redirect URI

Let's switch to the Application details page of Logto Console. Add a Redirect URI io.logto://callback and click "Save changes".

info:

The Redirect URI in iOS SDK is only for internal use. There's NO NEED to add a Custom URL Scheme until a connector asks.

Sign-in and sign-out

note:

Before calling .signInWithBrowser(redirectUri:), make sure you have correctly configured Redirect URI in Admin Console.

You can use client.signInWithBrowser(redirectUri:) to sign in the user and client.signOut() to sign out the user.

For example, in a SwiftUI app:

ContentView.swift

struct ContentView: View {
  @State var isAuthenticated: Bool

  init() {
    isAuthenticated = client.isAuthenticated
  }

  var body: some View {
    VStack {
      if isAuthenticated {
        Button("Sign Out") {
          Task { [self] in
            await client.signOut()
            isAuthenticated = false
          }
        }
      } else {
        Button("Sign In") {
          Task { [self] in
            do {
              try await client.signInWithBrowser(redirectUri: "${
                props.redirectUris[0] ?? 'io.logto://callback'
              }")
              isAuthenticated = true
            } catch let error as LogtoClientErrors.SignIn {
              // error occured during sign in
            } catch {
              // other errors
            }
          }
        }
      }
    }
  }
}

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 KOOK connector

To enable quick sign-in and improve user conversion, connect with iOS (Swift) 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 "KOOK".
3. Follow the README guide and complete required fields and customize settings.

note:

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

Set up KOOK OAuth app

Create an application in the KOOK Developer Center

Tips: You can skip some sections if you have already finished.

note:

You need to apply for KOOK OAuth2 permission before creating an OAuth2 Application. Please check out the information on the OAuth2 page or ask KOOK's staff in KOOK official developer server for more information.

1. Go to KOOK Developer Center and sign in with your KOOK account. You may register a new account if you don't have one.
2. Click the Create Application button to create an application, choose a name for it (e.g., LogtoAuth) and click Confirm
3. Click the application icon you created, and go to OAuth2 page.
4. Add the valid redirects (e.g., ${your_logto_origin}/callback/${connector_id}) in the Callback URIs fields. You can find the redirect uri in the logto admin console connector details page.
5. Don't forget to check the get_user_info scope in the OAuth2 link builder.

Configure your KOOK connector

Fill out the clientId and clientSecret fields with Client ID and Client Secret you've got from OAuth2 page mentioned in the previous section.

Config types

Name	Type
clientId	string
clientSecret	string
scope	string

Test KOOK connector

That's it. The KOOK connector should be available now. Don't forget to Enable connector in sign-in experience.

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 KOOK connector should be available now.

Enable KOOK connector in Sign-in Experience

Once you create a social connector successfully, you can enable it as a "Continue with KOOK" 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 KOOK connector to the "Social sign-in" section.

Testing and Validation

Return to your iOS (Swift) app. You should now be able to sign in with KOOK. 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.