lazy_load_hooks allows rails to lazily load a lot of components and thus
making the app boot faster. Because of this feature now there is no need to
require ActiveRecord::Base
at boot time purely to apply
configuration. Instead a hook is registered that applies configuration once
ActiveRecord::Base
is loaded. Here
ActiveRecord::Base
is used as example but this feature can be
applied elsewhere too.
Here is an example where on_load
method is called to register
a hook.
initializer "active_record.initialize_timezone" do ActiveSupport.on_load(:active_record) do self.time_zone_aware_attributes = true self.default_timezone = :utc end end
When the entirety of activerecord/lib/active_record/base.rb
has been evaluated then run_load_hooks
is invoked. The very
last line of activerecord/lib/active_record/base.rb
is:
ActiveSupport.run_load_hooks(:active_record, ActiveRecord::Base)
Namespace
- MODULE ActiveSupport