Class: Mediator::Instance

Inherits:
Object
  • Object
show all
Defined in:
lib/mediator.rb

Constant Summary collapse

MultipleHandlers = 
Class.new(StandardError)
UnregisteredHandler = 
Class.new(StandardError)

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Instance

Returns a new instance of Instance.



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# File 'lib/mediator.rb', line 12

def initialize
  @handlers = Concurrent::Map.new
  @listeners = Concurrent::Map.new { |h, k| h.compute_if_absent(k) { [] } }
end

Instance Method Details

#accept(request) ⇒ Object 



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# File 'lib/mediator.rb', line 27

def accept(request)
  handler!(request).then do |handler|
    handler.call(request)
  end
end

#handle(klass, handler) ⇒ Object

Raises:



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# File 'lib/mediator.rb', line 17

def handle(klass, handler)
  raise MultipleHandlers, "Multiple handlers not allowed for #{klass}" if handlers[klass]

  handlers[klass] = handler
end

#publish(event) ⇒ Object 



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# File 'lib/mediator.rb', line 33

def publish(event)
  listeners!(event).each do |listener|
    listener.call(event)
  end
end

#subscribe(klass, handler) ⇒ Object 



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# File 'lib/mediator.rb', line 23

def subscribe(klass, handler)
  listeners[klass] << handler
end