I use the excellent Exception Notifier plugin to receive warnings when exceptions occur in some of my rails apps.
The only problem was that one of the apps received hundreds upon thousands of 404s that were instead showing up as ActionController::RoutingErrors.
Simple enough fix, in vendor/plugins/exception_notification/lib/exception_notifier.rb, around line 38:
def exception_notification(exception, controller, request, data={})
# Disable notifications for 404s (ActionController::RoutingError)
return if (exception.message =~ /No route matches/)
...
Add the two lines below the function definition to disable these warnings.
Note: the error message changed between Rails 1.x and 2.0. The above works with Rails 2.x.
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