S3 Authentication

You have two options to authenticate with Supabase Storage S3:

• Using the generated S3 access keys from your project settings (Intended exclusively for server-side use)
• Using a Session Token, which will allow you to authenticate with a user JWT token and provide limited access via Row Level Security (RLS).

S3 access keys

To authenticate with S3, generate a pair of credentials (Access Key ID and Secret Access Key), copy the endpoint and region from the S3 configuration page.

This is all the information you need to connect to Supabase Storage using any S3-compatible service.

import { S3Client } from '@aws-sdk/client-s3';

const client = new S3Client({
  forcePathStyle: true,
  region: 'project_region',
  endpoint: 'https://project_ref.storage.supabase.co/storage/v1/s3',
  credentials: {
    accessKeyId: 'your_access_key_id',
    secretAccessKey: 'your_secret_access_key',
  }
})

# ~/.aws/credentials

[supabase]
aws_access_key_id = your_access_key_id
aws_secret_access_key = your_secret_access_key
endpoint_url = https://project_ref.storage.supabase.co/storage/v1/s3
region = project_region

Session token

You can authenticate to Supabase S3 with a user JWT token to provide limited access via RLS to all S3 operations. This is useful when you want initialize the S3 client on the server scoped to a specific user, or use the S3 client directly from the client side.

All S3 operations performed with the Session Token are scoped to the authenticated user. RLS policies on the Storage Schema are respected.

To authenticate with S3 using a Session Token, use the following credentials:

• access_key_id: project_ref
• secret_access_key: anonKey (publishableKey is not yet supported)
• session_token: valid jwt token

For example, using the aws-sdk library:

import { S3Client } from '@aws-sdk/client-s3'

const {
  data: { session },
} = await supabase.auth.getSession()

const client = new S3Client({
  forcePathStyle: true,
  region: 'project_region',
  endpoint: 'https://project_ref.storage.supabase.co/storage/v1/s3',
  credentials: {
    accessKeyId: 'project_ref',
    secretAccessKey: 'anonKey',
    sessionToken: session.access_token,
  },
})