Enable offline support in your Expo app

The Clerk Expo SDK provides enhanced offline support to improve reliability and user experience. This update enables your app to bootstrap offline using cached Clerk resources, ensuring quick initialization without requiring an internet connection.

It offers the following benefits:

• Initialization of the Clerk SDK is now more resilient to network failures.
• Faster resolution of the isLoaded property and the <ClerkLoaded> control component with only a single network fetch attempt. If the fetch fails, it gracefully falls back to cached resources.
• Network errors are no longer muted, allowing developers to catch and handle them effectively in their custom flows.
• The getToken() function in the useAuth() hook now supports returning cached tokens, minimizing disruptions caused by network failures.

How to enable offline support

To enable offline support in your Expo app, follow these steps:

npm install expo-secure-store

yarn add expo-secure-store

pnpm add expo-secure-store

import { ClerkProvider, ClerkLoaded } from '@clerk/clerk-expo'
import { Slot } from 'expo-router'
import { tokenCache } from '../token-cache'
import { secureStore } from '@clerk/clerk-expo/secure-store'

export default function RootLayout() {
  const publishableKey = process.env.EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY!

  if (!publishableKey) {
    throw new Error('Add EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY to your .env file')
  }

  return (
    <ClerkProvider
      publishableKey={publishableKey}
      tokenCache={tokenCache}
      __experimental_resourceCache={secureStore}
    >
      <ClerkLoaded>
        <Slot />
      </ClerkLoaded>
    </ClerkProvider>
  )
}

How to handle network errors

When there is no internet connection, Clerk's custom flows (e.g., signIn.create()) will throw a network error.

To handle network errors in your Expo app, you can use the isClerkRuntimeError() function to check if the error is a Clerk-related error. Clerk-related errors are returned as an array of ClerkAPIError objects. These errors contain a code property that you can use to identify the specific error. See the following example.

import { useSignIn, isClerkRuntimeError } from '@clerk/clerk-expo'
import { Link, useRouter } from 'expo-router'
import { Text, TextInput, Button, View } from 'react-native'
import React from 'react'

export default function SignInPage() {
  const { signIn, setActive, isLoaded } = useSignIn()
  const router = useRouter()

  const [emailAddress, setEmailAddress] = React.useState('')
  const [password, setPassword] = React.useState('')

  const onSignInPress = React.useCallback(async () => {
    if (!isLoaded) return
    try {
      const signInAttempt = await signIn.create({
        identifier: emailAddress,
        password,
      })

      // The rest of your custom flow logic
    } catch (err) {
      // See https://clerk.com/docs/custom-flows/error-handling
      // for more info on error handling
      if (isClerkRuntimeError(err) && err.code === 'network_error') {
        console.error('Network error occurred!')
      }

      console.error(JSON.stringify(err, null, 2))
    }
  }, [isLoaded, emailAddress, password])

  return (
    <View>
      <Button title="Sign in" onPress={onSignInPress} />
    </View>
  )
}