Fixing unknown OID: geography errors with PostGis and Rails 4.0

Recently, when migrating a large Rails application to Rails 4.0 that used PostGis,

I kept getting warnings like:

unknown OID: geography(1838124)

Thanks to

http://gray.fm/2013/09/17/unknown-oid-with-rails-and-postgresql/

I just added a file config/initializers/postgres_oids.rb with content:

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.tap do |klass|
# Use identity which does no casting
klass::OID.register_type('geography', klass::OID::Identity.new)
end