Rails 3.0 RC cannot capture exception when database goes down!

i found similar issues as i wrote some workers with the nanite gem and activerecord
and found myself hacking PostgreSQLAdapter AbstractAdapter and ConnectionPool..

best of all was that there is a ActiveRecord::ConnectionNotEstablished but its only used when no connection could be established at the beginning. If the connection is lost any time later PostgreSQLAdapter throws a PGError and AbstractAdapter simply converts this in a StatementInvalid exception.

The easiest way to go about this is to create your own middleware, and insert it before the ActiveRecord::QueryCache middleware in your application.rb. This middleware can catch the exception, rescue and do the self-healing bit.