Calling Methods from Inherited Class in Ruby - ruby

Question

I have the following classes:
Module
module AlertService
module MessageTemplate
def generate_message
"test"
end
end
end
Parent class:
module Client
def post uri, params={}
Net::HTTP.post_form uri, params
end
end
module AlertService
class BaseAlert
extend MessageTemplate
include Singleton
include Client
def initialize; end
end
end
Child Class:
module AlertService
class TestAlert < BaseAlert
include Singleton
def initialize
options = {
username: "Screen Alert Bot",
http_client: Client
}
#notifier = Slack::Notifier.new(rails.config.url, options)
end
def self.create_message
message = generate_message
end
def self.send_message
create_message
#notifier.post blocks: message
end
end
end
I can create the test alert like this: s= AlertService::TestAlert
But I get the error when I do this:
s.send_message
NoMethodError: undefined method `generate_message' for AlertService::TestAlert::Class
generate_message is a method from the MessageTemplate module included in the BaseAlert class. Why is it saying my inherited class doesn't have access to the method?

Answer 1

You're not using Singleton correctly. You're including it, but then not using it, instead bypassing that altogether and calling class methods that have nothing to do with Singleton. They're in turn calling class methods on the parent class that don't exist.
The solution is to use Singleton as intended:
module AlertService
class BaseAlert
include MessageTemplate
include Singleton
def initialize
end
end
end
module AlertService
class TestAlert < BaseAlert
def initialize
#notifier = Slack::Notifier.new(Rails.configuration.url, Rails.configuration.options)
end
def create_message
message = generate_message
end
def send_message
create_message
#notifier.post blocks: message
end
end
end
Where now you call with instance as documented:
AlertService::TestAlert.instance.send_message