How can I configure JWT authentication in n8n for secure Supabase connections?

n8n currently doesn’t offer a built‐in, global option for JWT-based authentication on its database connection or as part of every credential. In n8n, authentication for integrations (like the Supabase node or the Postgres node) is set up using static credentials—that is, you provide a fixed API key or other static connection details (e.g. Host, Service Role Secret for Supabase, or connection details for Postgres).

For example, the Supabase credentials documentation shows that you need to supply your Supabase Host and your Service Role Secret (an API key with elevated privileges) to authenticate your Supabase nodes. This is a one-time configuration rather than a dynamic JWT flow where a token is issued once and then automatically used in subsequent calls.

Likewise, when n8n connects to its Postgres database, it uses the connection details provided (via credentials or environment variables). There isn’t an option to configure the database connection to automatically request a JWT from Supabase and then use that token for all calls.

What Can You Do?

• Static Credentials: Continue using the static credentials method as documented. For Supabase, that means configuring the connection with your Project URL and your Service Role Secret. Note that exposing the service role isn’t ideal from a security standpoint but it is required for node connections.

• Alternative User/RLS Setup: Since your security warnings relate to RLS and the lack of authentication on calls, you might consider adjusting your Supabase RLS settings. One approach is to create a dedicated database user (or role) for n8n with the necessary privileges that bypass or are permitted under RLS policies. This user wouldn’t rely on a dynamic JWT flow but can be configured with a static secret.

• Custom Development: If JWT-based authentication on every call is essential to your setup, you’d have to look into custom developments. This might involve wrapping your database calls or using a proxy layer that handles a JWT handshake with Supabase. However, this isn’t supported out-of-the-box by n8n.

Summary

At this time, n8n’s integration credentials (including those for Supabase and Postgres) are configured statically and don’t provide a global (or per-credential) setting for JWT issuance and renewal. The recommended approach is to either adjust your RLS policies (or use a user that bypasses RLS limitations for trusted back-end connections) or build a custom solution if dynamic JWT handling is required.

Feel free to ask if you need further clarification on configuring the static credentials or managing RLS on Supabase!