How to refresh a session token in Supabase?

 

Step 1: Understand the Context

 

Before delving into code, it's essential to understand what a session token is. It’s a security credential used by Supabase to verify a user’s session. Once logged in with email/password, Supabase generates a session token. This token might expire, requiring a refresh to re-authenticate the session without the user having to log in again.

 

Step 2: Setup your Supabase Environment

 

Ensure you have the Supabase setup in your development environment. If you haven't already, install the @supabase/supabase-js package using npm or yarn.

npm install @supabase/supabase-js

or

yarn add @supabase/supabase-js

You'll also need to create a Supabase project from their dashboard and get the API URL and anon key.

 

Step 3: Initialize Your Supabase Client

 

Start by initializing your Supabase client in your application. Import the necessary functions and create a Supabase client using your API details.

import { createClient } from '@supabase/supabase-js'

const supabaseUrl = 'YOUR_SUPABASE_URL'
const supabaseAnonKey = 'YOUR_SUPABASE_ANON\_KEY'

const supabase = createClient(supabaseUrl, supabaseAnonKey)

Replace the placeholders YOUR_SUPABASE_URL and YOUR_SUPABASE_ANON_KEY with your actual Supabase project URL and anonymous key.

 

Step 4: Listening for Token Expiry

 

Supabase client automatically refreshes session tokens. However, to handle custom logic upon token refresh, you can listen for any authentication state changes:

supabase.auth.onAuthStateChange((event, session) => {
  if (event === 'TOKEN\_REFRESHED') {
    console.log('Token has been refreshed:', session)
  }
})

This function logs the new session whenever the token is refreshed.

 

Step 5: Refresh Token Manually (if needed)

 

While Supabase handles token refresh automatically, you might encounter scenarios where you need to perform this manually. To perform a manual refresh, check if a session exists and invoke the refresh method:

const refreshSessionToken = async () => {
  const { session, error } = await supabase.auth.refreshSession()

  if (error) {
    console.error('Error refreshing session:', error)
  } else {
    console.log('Session refreshed:', session)
  }
}

refreshSessionToken()

Note that this method might not be available in all SDK versions. Always refer to the most recent documentation for updates.

 

Step 6: Store the Updated Session

 

Ensure to store the refreshed session either in your app's state or local storage if you rely on this data for subsequent API requests or user session management.

localStorage.setItem('supabase.auth.token', JSON.stringify(session))

 

Conclusion

 

This tutorial provided a comprehensive guide to understand and implement session token refresh in Supabase. It involves initializing the Supabase client, listening for session token events, manually refreshing tokens if necessary, and storing refreshed sessions for application use. Always refer to the Supabase documentation for any updates or changes in the SDK.