Listener to bust cache key for event

cache_buster.rb

# Cache buster

# Generic object which will invalidate a cache key for an event.

class CacheBuster
  def initialize(dependencies = {})
    @cache = dependencies.fetch(:cache) { Rails.cache }
  end
  
  def self.build(options)
    new.tap do |instance| 
      instance.cache_key = options.fetch(:cache_key)
      instance.event_name = options.fetch(:event_name)
    end
  end
  
  def method_missing(name, _)
    if event_name == name.to_s
      @cache.delete(cache_key)
    else
      super
    end
  end
  
  def respond_to?(name)
    event_name == name.to_s || super
  end
end

# usage
command.subscribe(CacheBuster.build(cache_key: :quick_search, event: :on_field_updated))