Class: Omnes::Subscription

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

Overview

Subscription to an event

An instance of it is returned on Bus subscription methods.

Usually, it isn't used directly beyond as a reference to unsubscribe.

bus = Omnes::Bus.new
bus.register(:foo)
subscription = bus.subscribe(:foo) { |_event| do_something }
bus.unsubscribe(subscription)

Constant Summary collapse

SINGLE_EVENT_MATCHER = 
lambda do |subscribed, candidate|
  subscribed == candidate.omnes_event_name
end
ALL_EVENTS_MATCHER = 
->(_candidate) { true }

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(matcher:, callback:, id:) ⇒ Subscription

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Subscription.

Raises:



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# File 'lib/omnes/subscription.rb', line 41

def initialize(matcher:, callback:, id:)
  raise Omnes::InvalidSubscriptionNameError.new(id: id) unless id.is_a?(Symbol)

  @matcher = matcher
  @callback = callback
  @id = id
end

Instance Attribute Details

#callback ⇒ Object (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/omnes/subscription.rb', line 38

def callback
  @callback
end

#id ⇒ Object (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/omnes/subscription.rb', line 38

def id
  @id
end

#matcher ⇒ Object (readonly)

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/omnes/subscription.rb', line 38

def matcher
  @matcher
end

Class Method Details

.random_id ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/omnes/subscription.rb', line 28

def self.random_id
  SecureRandom.uuid.to_sym
end

.takes_publication_context?(callable) ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns:

  • (Boolean) 


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# File 'lib/omnes/subscription.rb', line 33

def self.takes_publication_context?(callable)
  callable.parameters.count == 2
end

Instance Method Details

#call(event, publication_context) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/omnes/subscription.rb', line 50

def call(event, publication_context)
  result = nil
  benchmark = Benchmark.measure do
    # work around Ruby not being able to tell remaining arity for a curried
    # function (or uncurrying), because we want to be able to create subscriber
    # adapters partially applying the subscriber instance
    result = begin
      @callback.(event, publication_context)
    rescue ArgumentError
      @callback.(event)
    end
  end

  Execution.new(subscription: self, result: result, benchmark: benchmark)
end

#matches?(candidate) ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns:

  • (Boolean) 


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# File 'lib/omnes/subscription.rb', line 67

def matches?(candidate)
  matcher.(candidate)
end

#subscriptions ⇒ Object

Returns self within a single-item array

This method can be helpful to act polymorphic to an array of subscriptions from an Omnes::Subscriber, usually for testing purposes.



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# File 'lib/omnes/subscription.rb', line 75

def subscriptions
  [self]
end