Class: DynamicRegistrar::Registrar

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

Overview

Controls the registration and dispatching of callbacks

Constant Summary collapse

@@registration_guard =

Mutex to provide for no double or overwritten registration guarantee even in multithreaded environments

Mutex.new

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(default_registration_namespace) ⇒ Registrar

Create a new DynamicRegistrar::Registrar

Parameters:

  • default_registration_namespace (Symbol) —

    The default namespace in which to register callbacks. Should not be set to nil.



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# File 'lib/dynamic_registrar/registrar.rb', line 25

def initialize default_registration_namespace
  @default_registration_namespace = default_registration_namespace
  @registered_callbacks = Hash.new
end

Instance Attribute Details

#default_registration_namespace ⇒ Object (readonly)

The default namespace used when calling Registrar#register! without specifying a namespace



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# File 'lib/dynamic_registrar/registrar.rb', line 14

def default_registration_namespace
  @default_registration_namespace
end

Instance Method Details

#dispatch(name, namespace = nil) ⇒ Hash

Dispatch message to given callback. All named callbacks matching the name will be run in all namespaces in indeterminate order

Parameters:

  • name (Symbol) —

    The name of the callback

  • namespace (Symbol) (defaults to: nil) —

    The namespace in which the named callback should be found. Optional, if omitted then all matching named callbacks in all namespaces will be executed

Returns:

  • (Hash) —

    A hash whose keys are the namespaces in which callbacks were executed, and whose values are the results of those executions. If empty, then no callbacks were executed.



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# File 'lib/dynamic_registrar/registrar.rb', line 46

def dispatch name, namespace = nil
  responses = Hash.new
  namespaces_to_search = namespace ? [namespace] : namespaces
  namespaces_to_search.each do |namespace|
    responses[namespace] ||= Hash.new
    responses[namespace][name] = @registered_callbacks[namespace][name].call if @registered_callbacks[namespace].has_key?(name)
  end
  responses
end

#register!(name, namespace = @default_registration_namespace, &callback_proc) ⇒ Object

Register a new callback procedure. This method is thread-safe.

Parameters:

  • name (Symbol) —

    The name of the callback to register

  • namespace (Symbol) (defaults to: @default_registration_namespace) —

    The namespace in which to register the callback



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# File 'lib/dynamic_registrar/registrar.rb', line 33

def register! name, namespace = @default_registration_namespace, &callback_proc
  @@registration_guard.synchronize do
    raise Errors::RegistrationConflictError if registered_in_namespace? name, namespace
    @registered_callbacks[namespace] ||= Hash.new
    @registered_callbacks[namespace][name] = callback_proc
  end
end

#registered?(name) ⇒ Boolean

Query if a callback of given name is registered in any namespace

Parameters:

  • name (Symbol) —

    The name of the callback to check

Returns:

  • (Boolean) 


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# File 'lib/dynamic_registrar/registrar.rb', line 58

def registered? name
  registration_map = namespaces.map do |namespace|
    registered_in_namespace? name, namespace
  end
  registration_map.any?
end

#registered_callbacks ⇒ Object

The collection of callbacks currently registered within the Registrar



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# File 'lib/dynamic_registrar/registrar.rb', line 17

def registered_callbacks
  @@registration_guard.synchronize do
    @registered_callbacks
  end
end

#registered_in_namespace?(name, namespace) ⇒ Boolean

Query if a callback of given name is registered in given namespace

Parameters:

  • name (Symbol) —

    The name of the callback to check

  • namespace (Symbol) —

    The name of the namespace in which to check

Returns:

  • (Boolean) 


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# File 'lib/dynamic_registrar/registrar.rb', line 68

def registered_in_namespace? name, namespace
  @registered_callbacks.has_key?(namespace) && @registered_callbacks[namespace].has_key?(name)
end