I’m working on my first project that uses Google’s OAuth2 system along with the Drive API. Everything seems to work fine until I get to the authorization screen from Google. After I click the allow button, my application just stops responding and doesn’t move forward with the authentication process.
The redirect URL that Google sends me to shows a 404 error page instead of completing the OAuth flow. I’m getting a callback URL that looks something like this:
I suspect there might be something wrong with my redirect URI configuration or how I’m handling the callback in my application. Has anyone encountered this issue before? What could be causing the authentication flow to break at this point?
Been there, done that. OAuth flows are a nightmare to debug, especially when you’re manually handling callbacks and token exchanges.
Your callback URL gets the code parameter fine, so Google’s working. The 404 means your app either crashed or doesn’t have a route handler running when Google hits that endpoint.
After years of OAuth headaches, I just automate the whole flow now. No more wrestling with callback routes, token refreshes, or state management. Set up authentication once, connect your Google Drive API calls, and let automation handle token exchanges and error handling.
I’ve built dozens of integrations this way and never think about OAuth details again. The platform handles redirect URI setup, token storage, and API calls seamlessly.
check if your server actually restarted after adding the callback route - caught me out before. also try hitting localhost:8080 directly in your browser to see if anything’s running there at all.
Had this same issue when I started using OAuth2 with Google’s API. Your app server probably isn’t listening on the callback route when Google tries to redirect back. Sure, you’ve got the redirect URI set up in Google Console, but your local app needs an actual endpoint running on that path. Make sure your server’s running and has a route handler for the root path - Google’s trying to hit http://localhost:8080/. Double-check that your redirect URI in Google Console matches exactly what you’re using in the auth request. Even tiny mismatches will break authentication.
This happened to me on my first OAuth implementation too. The issue probably isn’t your callback handler - it’s likely your dev server is configured for a different path than what you registered in Google Console. I spent hours debugging routes when the real problem was my server expected requests at /auth/callback but I’d registered just / in the console. Check your Google Console OAuth credentials and make sure the redirect URI exactly matches where your server expects the callback. Also test if your server handles GET requests properly on that path - some frameworks need explicit route definitions even for root paths.
Had this exact same issue during my second OAuth project - super frustrating. Your callback URL looks fine, so Google’s doing its job. The problem’s on your end - your server isn’t handling the authorization code properly. When this happened to me, I realized my dev server was running but I’d never actually built the callback handler route. You need an endpoint that grabs the authorization code from the query params and swaps it for access tokens. Also check if your server’s actually listening on port 8080 and not silently crashing when the callback hits.
totally sounds like a redirect uri issue. make sure your app is set to handle that endpoint at localhost:8080. a 404 means it can’t find it when google sends the response, so check your route!