Rails 5.2 specifying default value for class_attribute

Vishal Telangre

By Vishal Telangre

on February 21, 2018

This blog is part of our  Rails 5.2 series.

It is very common to set a default value for a class_attribute.

Before Rails 5.2, to specify a default value for a class_attribute, we needed to write like this.

1class ActivityLogger
2class_attribute :logger
3class_attribute :settings
4
5self.logger = Logger.new(STDOUT)
6self.settings = {}
7end

As we can see above, it requires additional keystrokes to set a default value for each class_attribute.

Rails 5.2 has added support for specifying a default value for a class_attribute using default option.

1class ActivityLogger
2class_attribute :logger, default: Logger.new(STDOUT)
3class_attribute :settings, default: {}
4end

This enhancement was introduced in this pull request.