Common Rails error you will (most probably) see in your log file

Phil Nash wrote a great article about common Rails errors and how to deal with them.

The common errors are:

1. ActionController::RoutingError

2. NoMethodError: undefined method ‘[]’ for nil:NilClass

3. ActionController::InvalidAuthenticityToken

4. Net::ReadTimeout

5. ActiveRecord::RecordNotUnique: PG::UniqueViolation

6. NoMethodError: undefined method ‘id’ for nil:NilClass

7. ActionController::ParameterMissing

8. ActionView::Template::Error: undefined local variable or method

9. ActionController::UnknownFormat

10. StandardError: An error has occurred, this and all later migrations canceled

Each section comes with a probable explanation of the cause, and how to best deal with it. Great article!

https://rollbar.com/blog/top-10-ruby-on-rails-errors