ctx is a NextJS artifact. ctx is a context object containing those properties (Source): pathname - path section of URL query - query string section of URL parsed as an object asPath - String of the actual path (including the query) shows in the browser req - HTTP request object (server only) res - HTTP response object (server only) err - Error object if any error is encountered during the rendering
Here is what the above code is Doing:
1. If the user is not logged in, redirect them to the login page.
2. If the user is logged in, redirect them to the home page.