How to combine Supabase Google Auth and Google App Permissions in a Next.js Application

Integrating Google authentication with Supabase and Nylas in a Next.js application allows for seamless authentication and access to a user's email and calendar data. Initially, Google Supabase Auth is used to authenticate the user and obtain a refresh token, which is then passed to Nylas to create a grant for accessing email and calendar functionalities. The process involves setting up a Google Cloud Project with necessary API scopes, configuring OAuth consent, and integrating Nylas Custom Authentication using the provider refresh token. Testing with tools like Postman ensures the configuration is correct before integration. By combining Supabase for initial authentication and Nylas for extended permissions, developers can provide users with a unified login experience that supports both standard and advanced functionalities. This integration enables developers to build applications that efficiently leverage Google's and Nylas's capabilities for email and calendar operations.