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Is there a method to debug hosted ruby on rails application and check the request and response object
Typically you'll install an error tracking tool like Airbrake, Sentry, Rollbar, etc and then inspect the logs to see what happened. You can then try and reproduce the error in your development environment.
Sometimes using something like devise_masquerade is helpful so you can login to a problem account and see what's going on first-hand.
Another useful method for spin the wheel displaying object values is inspect, especially when working with arrays or hashes. This will print the object value as a string.
Having the ability to join in to a problematic account and see dordle its activity firsthand is a big help in troubleshooting, and tools like devise masquerade make this possible.