@descope/react-native-sdk

Descope SDK for React Native

The Descope SDK for React Native provides convenient access to Descope for an application written on top of React Native. You can read more on the Descope Website.

Requirements

• A Descope Project ID is required for using the SDK. Find it on the project page in the Descope Console.

Installing the SDK

Install the package with:

yarn add @descope/react-native-sdk
# or
npm i --save @descope/react-native-sdk

When targeting iOS, make sure to navigate into the ios folder and install the dependencies:

pod install

Usage

Wrap your app with Auth Provider

import { AuthProvider } from '@descope/react-native-sdk'

const AppRoot = () => {
  return (
    <AuthProvider
      projectId="my-project-id"
      // If the Descope project manages the token response in cookies, a custom domain
      // must be configured (e.g., https://auth.app.example.com)
      // and should be set as the baseUrl property.
      // baseUrl = "https://auth.app.example.com"
    >
      <App />
    </AuthProvider>
  )
}

Session Management

The useSession hook is used to manage an authenticated user session for an application.

The session manager takes care of loading and saving the session as well as ensuring that it's refreshed when needed. When the user completes a sign in flow successfully you should set the DescopeSession as the active session of the session manager.

import { useDescope, useSession } from '@descope/react-native-sdk'

const descope = useDescope()
const { manageSession } = useSession()

const resp = await descope.otp.email.verify('[e-mail]', '123456')
manageSession(resp.data)

The session manager can then be used at any time to ensure the session is valid and to authenticate outgoing requests to your backend with a bearer token authorization header.

const { session } = useSession()

const res = await fetch('/path/to/server/api', {
  headers: {
    Authorization: `Bearer ${session.sessionJwt}`,
  },
})

When the application is relaunched the AuthProvider component will automatically load any existing session. Once the isSessionLoading flag is false, you can check if there's a session available (i.e. an authenticated user).

When the user wants to sign out of the application we revoke the active session and clear it from the session manager:

import { useDescope, useSession } from '@descope/react-native-sdk'

const descope = useDescope()
const { session, clearSession } = useSession()

await descope.logout(session.refreshJwt)
await clearSession(resp.data)

Accessing the Session

The session information can be accessed via the useSession hook, but also it might be convenient to use the getCurrentSessionToken(), getCurrentRefreshToken() and getCurrentUser() helper functions. These functions are available outside of the component render-lifecycle. This might be useful, for example, to add an authorization header to all authenticated requests.

Refreshing the Session

The guiding principal of refreshing the session is the same, regardless of any specific app architecture or network framework.

Before every authenticated request, add your authorization header to the request the way your server expects to receive it. As an optimization it is also possible to call refreshSessionIfAboutToExpire(). This async function will preemptively refresh the session token if it is about to expire, or already expired. That code might look something like this:

// ... before every authenticated request
try {
  // refresh if needed
  await refreshSessionIfAboutToExpire()
} catch (e) {
  // fail silently - as this shouldn't affect the request being performed
}

// add authorization header
request.headers.Authorization = `Bearer ${getCurrentSessionToken()}`

After every error response - if the server responds that the session token is invalid, i.e. 401 or your equivalent, try to refresh the session token and repeat the request. Otherwise, clear the session and prompt the user to re-authenticate. That code might look something like this

// ... on every error response
// assuming 401 is returned ONLY when the session JWT is invalid
if (error.status === 401) {
  try {
    const resp = await descope.refresh(getCurrentRefreshToken())
    await updateTokens(resp.data.sessionJwt, resp.data.refreshJwt)

    // you can now retry the original request
    // NEED TO MAKE SURE THAT THIS RETRY IS ONLY PERFORMED ONCE
    // otherwise, an endless loop of failed requests might occur
    retryRequest()
  } catch (e) {
    // clear the session as the user must re-authenticate
  }
}

IMPORTANT NOTE: if you find the need to pass a reference to the refreshSessionIfAboutToExpire() updateTokens() and descope from the useSession hook into some network component, make sure it is done in a lifecycle aware method. That code might look something like this:

const descope = useDescope()
const { isSessionLoading, refreshSessionIfAboutToExpire, updateTokens } = useSession()

React.useEffect(() => {
  if (!isSessionLoading) {
    setUpNetworkRefresh(refreshSessionIfAboutToExpire, updateTokens, descope)
  }
}, [isSessionLoading refreshSessionIfAboutToExpire, updateTokens, descope])

Running Flows

We can authenticate users by building and running Flows. Flows are built in the Descope flow editor. The editor allows you to easily define both the behavior and the UI that take the user through their authentication journey. Read more about it in the Descope getting started guide.

Setup #1: Define and host your flow

Before we can run a flow, it must first be defined and hosted. Every project comes with predefined flows out of the box. You can customize your flows to suit your needs and host it. Follow the getting started guide for more details. You can host the flow yourself or leverage Descope's hosted flow page. Read more about it here. You can also check out the auth-hosting repo itself.

(Android Only) Setup #2: Enable App Links

Running a flow via the React Native SDK, when targeting Android, requires setting up App Links. This is essential for the SDK to be notified when the user has successfully authenticated using a flow. Once you have a domain set up and verified for sending App Links, you'll need to handle the incoming deep links in your app:

Define a route to handle the App Link sent at the end of a flow

this code example demonstrates how app links should be handled - you can customize it to fit your app

import { useFlow } from '@descope/react-native-sdk'

const flow = useFlow()

useEffect(() => {
  Linking.addEventListener('url', async (event) => {
    if (event.url === 'my-deep-link-for-authenticating') {
      // This path needs to correspond to the deep link you configured in your manifest - see below
      try {
        await flow.exchange(event.url) // Call exchange to complete the flow
      } catch (e) {
        // Handle errors here
      }
    }
  })
  return () => {
    Linking.removeAllListeners('url')
  }
}, [flow])

Add a matching Manifest declaration

<activity
        android:name=".MainActivity"
        android:exported="true"
        android:launchMode="singleTask"
        android:theme="@style/LaunchTheme"
        android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
        android:hardwareAccelerated="true"
        android:windowSoftInputMode="adjustResize">

    <!-- add the following at the end of the activity tag, after anything you have defined currently -->

    <intent-filter android:autoVerify="true"> <!-- autoVerify required for app links -->
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />
        <!-- replace with your host, the path can change must must be reflected when running the flow -->
        <!-- the path should correspond with the routing path defined above -->
        <data android:scheme="https" android:host="<YOUR_HOST_HERE>" android:path="/auth" />
        <!-- see magic link setup below for more details -->
        <data android:scheme="https" android:host="<YOUR_HOST_HERE>" android:path="/magiclink" />
    </intent-filter>

    <!-- Optional: App Links are blocked by default on Opera and some other browsers. Add a custom scheme for that use case specifically -->
    <intent-filter android:autoVerify="true">
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />

        <!-- replace with something unique. this will only be used as a backup for Opera and some other browsers. -->
        <data android:scheme="myapp" android:host="auth" />
    </intent-filter>
</activity>

(OPTIONAL) Setup #3: Support Magic Link Redirects

Supporting Magic Link authentication in flows requires some platform specific setup:

• On Android: add another path entry to the App Links. This is essentially another path in the same as the app link from the previous setup step, with different handling logic. Refer to the previous section for the manifest setup.
• On iOS: You'll need to support associated domains.

Regardless of the platform, another path is required to handle magic link redirects specifically. For the sake of this README, let's name it /magiclink

Add the required Linking logic

this code example demonstrates how app links or universal links should be handled - you can customize it to fit your app

import { useFlow } from '@descope/react-native-sdk'

const flow = useFlow()

useEffect(() => {
  Linking.addEventListener('url', async (event) => {
    if (event.url === 'my-deep-link-for-authenticating') {
      try {
        await flow.exchange(event.url) // Call exchange to complete the flow
      } catch (e) {
        // Handle errors here
      }
    } else if (event.url === 'my-deep-link-for-magic-links') {
      // Adding the magic link handling here
      try {
        await flow.resume(event.url) // Resume the flow after returning from a magic link
      } catch (e) {
        // Handle errors here
      }
    }
  })
  return () => {
    Linking.removeAllListeners('url')
  }
}, [flow])

Run a Flow

After completing the prerequisite steps, it is now possible to run a flow. The flow will run in a Custom Tab on Android, or via ASWebAuthenticationSession on iOS. Run the flow by calling the flow start function:

import { useFlow } from '@descope/react-native-sdk'

const flow = useFlow()
const { session, manageSession } = useSession()

try {
  // When starting a flow for an authenticated user, provide the authentication info
  let flowAuthentication
  if (session) {
    flowAuthentication = {
      flowId: 'flow-id',
      refreshJwt: session.refreshJwt,
    }
  }
  const resp = await flow.start('<URL_FOR_FLOW_IN_SETUP_#1>', '<URL_FOR_APP_LINK_IN_SETUP_#2>', '<OPTIONAL_CUSTOM_SCHEME_FROM_SETUP_#2>', flowAuthentication)
  await manageSession(resp.data)
} catch (e) {
  // handle errors
}

When running on iOS nothing else is required. When running on Android, flow.exchange() function must be called. See the app link setup for more details.

Use the useDescope and useSession hooks in your components in order to get authentication state, user details and utilities

This can be helpful to implement application-specific logic. Examples:

• Render different components if current session is authenticated
• Render user's content
• Logout button

import { useDescope, useSession } from '@descope/react-native-sdk'
import { useCallback } from 'react'

const App = () => {
  // NOTE - `useDescope`, `useSession`, should be used inside `AuthProvider` context,
  // and will throw an exception if this requirement is not met
  const { session } = useSession()
  const { logout } = useDescope()

  const handleLogout = useCallback(() => {
    logout()
  }, [logout])

  if (session) {
    return (
      <>
        <p>Hello {session.user.name}</p>
        <button onClick={handleLogout}>Logout</button>
      </>
    )
  }

  return <p>You are not logged in</p>
}

For more SDK usage examples refer to docs

Learn More

To learn more please see the Descope Documentation and API reference page.

Contact Us

If you need help you can email Descope Support

License

The Descope SDK for React Native is licensed for use under the terms and conditions of the MIT license Agreement.