Use Supabase Auth with React Native | Supabase English

Quickstart

Create a new Supabase project

Launch a new project in the Supabase Dashboard.

Your new database has a table for storing your users. You can see that this table is currently empty by running some SQL in the SQL Editor.
```
 select * from auth.users;
```
Create a React app

Create a React app using the create-expo-app command.
```
npx create-expo-app -t expo-template-blank-typescript my-app
```

Install the Supabase client library

Install supabase-js and the required dependencies.

cd my-app && npx expo install @supabase/supabase-js @react-native-async-storage/async-storage @rneui/themed react-native-url-polyfill

Set up your sign-in component

Create a helper file lib/supabase.ts that exports a Supabase client using your Project URL and key.

Rename .env.example to .env and populate with your Supabase connection variables:

Project URL: https://<project-ref>.supabase.co (find yours in the dashboard)

Publishable key: sb_publishable_... (find yours in the dashboard)

import { AppState, Platform } from 'react-native'
import 'react-native-url-polyfill/auto'
import AsyncStorage from '@react-native-async-storage/async-storage'
import { createClient } from '@supabase/supabase-js'

const supabaseUrl = process.env.EXPO_PUBLIC_SUPABASE_URL!
const supabasePublishableKey = process.env.EXPO_PUBLIC_SUPABASE_PUBLISHABLE_KEY!

export const supabase = createClient(supabaseUrl, supabasePublishableKey, {
  auth: {
    ...(Platform.OS !== 'web' ? { storage: AsyncStorage } : {}),
    autoRefreshToken: true,
    persistSession: true,
    detectSessionInUrl: false,
  },
})

// Tells Supabase Auth to continuously refresh the session automatically
// if the app is in the foreground. When this is added, you will continue
// to receive `onAuthStateChange` events with the `TOKEN_REFRESHED` or
// `SIGNED_OUT` event if the user's session is terminated. This should
// only be registered once.
if (Platform.OS !== 'web') {
  AppState.addEventListener('change', (state) => {
    if (state === 'active') {
      supabase.auth.startAutoRefresh()
    } else {
      supabase.auth.stopAutoRefresh()
    }
  })
}

Get API details

To interact with data in database tables, you use the client libraries that wrap the auto-generated Data API endpoints, authenticating using the Project URL and key from the project Connect dialog.

Project URL: https://<project-ref>.supabase.co (find yours in the dashboard)

Publishable key: sb_publishable_... (find yours in the dashboard)

Note

See API keys for a full explanation of all key types, their uses, and where to find them.

Create a sign-in component

Create a React Native component to manage sign-ins and sign-ups. The app later uses the getClaims method in App.tsx to validate the local JWT before showing the signed-in user.

import React, { useState } from 'react'
import { Alert, StyleSheet, View, Text, TextInput, TouchableOpacity } from 'react-native'
import { supabase } from '../lib/supabase'

export default function Auth() {
  const [email, setEmail] = useState('')
  const [password, setPassword] = useState('')
  const [loading, setLoading] = useState(false)

  async function signInWithEmail() {
    setLoading(true)
    const { error } = await supabase.auth.signInWithPassword({
      email: email,
      password: password,
    })

    if (error) Alert.alert(error.message)
    setLoading(false)
  }

  async function signUpWithEmail() {
    setLoading(true)
    const {
      data: { session },
      error,
    } = await supabase.auth.signUp({
      email: email,
      password: password,
    })

    if (error) Alert.alert(error.message)
    if (!session) Alert.alert('Please check your inbox for email verification!')
    setLoading(false)
  }

  return (
    <View style={styles.container}>
      <View style={[styles.verticallySpaced, styles.mt20]}>
        <Text style={styles.label}>Email</Text>
        <TextInput
          onChangeText={(text) => setEmail(text)}
          value={email}
          placeholder="email@address.com"
          autoCapitalize="none"
          style={styles.input}
        />
      </View>
      <View style={styles.verticallySpaced}>
        <Text style={styles.label}>Password</Text>
        <TextInput
          onChangeText={(text) => setPassword(text)}
          value={password}
          secureTextEntry={true}
          placeholder="Password"
          autoCapitalize="none"
          style={styles.input}
        />
      </View>
      <View style={[styles.verticallySpaced, styles.mt20]}>
        <TouchableOpacity
          style={[styles.button, loading && styles.buttonDisabled]}
          onPress={() => signInWithEmail()}
          disabled={loading}
        >
          <Text style={styles.buttonText}>Sign in</Text>
        </TouchableOpacity>
      </View>
      <View style={styles.verticallySpaced}>
        <TouchableOpacity
          style={[styles.button, loading && styles.buttonDisabled]}
          onPress={() => signUpWithEmail()}
          disabled={loading}
        >
          <Text style={styles.buttonText}>Sign up</Text>
        </TouchableOpacity>
      </View>
    </View>
  )
}

const styles = StyleSheet.create({
  container: {
    marginTop: 40,
    padding: 12,
  },
  verticallySpaced: {
    paddingTop: 4,
    paddingBottom: 4,
    alignSelf: 'stretch',
  },
  mt20: {
    marginTop: 20,
  },
  label: {
    fontSize: 16,
    fontWeight: '600',
    color: '#86939e',
    marginBottom: 6,
  },
  input: {
    borderWidth: 1,
    borderColor: '#86939e',
    borderRadius: 4,
    padding: 12,
    fontSize: 16,
  },
  button: {
    backgroundColor: '#2089dc',
    borderRadius: 4,
    padding: 12,
    alignItems: 'center',
  },
  buttonDisabled: {
    opacity: 0.5,
  },
  buttonText: {
    color: '#fff',
    fontSize: 16,
    fontWeight: '600',
  },
})

Add the Auth component to your app

Add the Auth component to your App.tsx file. If the user is signed in, print the user id to the screen.

import 'react-native-url-polyfill/auto'
import { useState, useEffect } from 'react'
import { supabase } from './lib/supabase'
import Auth from './components/Auth'
import { View, Text } from 'react-native'
import { JwtPayload } from '@supabase/supabase-js'

export default function App() {
  const [claims, setClaims] = useState<JwtPayload | null>(null)

  useEffect(() => {
    supabase.auth.getClaims().then(({ data: { claims } }) => {
      setClaims(claims)
    })

    supabase.auth.onAuthStateChange(() => {
      supabase.auth.getClaims().then(({ data: { claims } }) => {
        setClaims(claims)
      })
    })
  }, [])

  return (
    <View>
      <Auth />
      {claims && <Text>{claims.sub}</Text>}
    </View>
  )
}

Start the app

Start the app, and follow the instructions in the terminal.
```
npm start
```