From: James Edward Gray II <james@...>
Date: 2007-03-27T03:11:57+09:00
Subject: Re: How to handle "System Exceptions" vs "Application Errors" vs "Audit Events" in a Rails App???

On Mar 21, 2007, at 6:48 AM, Greg Hauptmann wrote:

> Hi all,

Hello.

> Just trying to cement by understanding of how to handle system
> exceptions/application errors/audit events for a Ruby on Rails  
> application.
> How do people personally handle the following categories of events.

I'll add my personal opinions.

> a) Uncaught exceptions (i.e. bubble up to top)

At my company, we use this option:

>   - Alerting: Use of "exception_notification" plugin.

I highly recommend it.  In fact, have this in place very early in  
development.  I often fix bugs using the information it provides,  
before the client can even email me to report it.  ;)

> b) Trapped exceptions (i.e. handle explicitly)
>   - Usage: Understood application error (not system error)
>            / Developer can offer value add
>   - Logging: Issue a "logger.error" line
>   - Alerting: How to hook into "exception_notification"
>               plugin?

I'm not sure I understand the question here.  If you trapped the  
error, you need to deal with it as make sense.  That includes  
recording it, if that's useful information, and giving the user a  
helpful error message.

> c) Application Specific Audit
>   - Usage: For application specific event (e.g. sale
>     has occurred) and want an email alert and log it too.
>   - Logging: Via use of "logger.info" system (? or need
>     custom solution for audit logging?)
>   - Alerting: How to hook into "exception_notification"
>               plugin from this point?

This sounds like a great candidate for a before_filter.  If you place  
all the controllers you wish to monitor in a hierarchy, you can set  
the filter on the parent controller and add whatever handling is  
appropriate.

Hope this helps.

James Edward Gray II