Class: Wayback::Base

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

Direct Known Subclasses

Identity

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(attrs = {}) ⇒ Wayback::Base

Initializes a new object

Parameters:

  • attrs (Hash) (defaults to: {}) 


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# File 'lib/wayback/base.rb', line 79

def initialize(attrs={})
  @attrs = attrs
end

Class Method Details

.attr_reader(*attrs) ⇒ Object

Define methods that retrieve the value from an initialized instance variable Hash, using the attribute as a key

Parameters:

  • attrs (Array, Set, Symbol) 


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# File 'lib/wayback/base.rb', line 8

def self.attr_reader(*attrs)
  mod = Module.new do
    attrs.each do |attribute|
      define_method attribute do
        @attrs[attribute.to_sym]
      end
      define_method "#{attribute}?" do
        !!@attrs[attribute.to_sym]
      end
    end
  end
  const_set(:Attributes, mod)
  include mod
end

.fetch(attrs) ⇒ Wayback::Base

Retrieves an object from the identity map.

Parameters:

  • attrs (Hash)

Returns:

Raises:



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# File 'lib/wayback/base.rb', line 34

def self.fetch(attrs)
  return unless identity_map
  if object = identity_map.fetch(Marshal.dump(attrs))
    return object
  end
  return yield if block_given?
  raise Wayback::Error::IdentityMapKeyError, "key not found"
end

.fetch_or_new(attrs = {}) ⇒ Wayback::Base

Retrieves an object from the identity map, or stores it in the identity map if it doesn't already exist.

Parameters:

  • attrs (Hash) (defaults to: {})

Returns:



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# File 'lib/wayback/base.rb', line 65

def self.fetch_or_new(attrs={})
  return unless attrs
  return new(attrs) unless identity_map

  fetch(attrs) do
    object = new(attrs)
    store(object)
  end
end

.from_response(response = {}) ⇒ Wayback::Base

Returns a new object based on the response hash

Parameters:

  • response (Hash) (defaults to: {})

Returns:



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# File 'lib/wayback/base.rb', line 56

def self.from_response(response={})
  fetch_or_new(response[:body])
end

.identity_map ⇒ Object

return [Wayback::IdentityMap]



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# File 'lib/wayback/base.rb', line 24

def self.identity_map
  return unless Wayback.identity_map
  @identity_map = Wayback.identity_map.new unless defined?(@identity_map) && @identity_map.class == Wayback.identity_map
  @identity_map
end

.store(object) ⇒ Wayback::Base

Stores an object in the identity map.

Parameters:

  • object (Object)

Returns:



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# File 'lib/wayback/base.rb', line 47

def self.store(object)
  return object unless identity_map
  identity_map.store(Marshal.dump(object.attrs), object)
end

Instance Method Details

#[](method) ⇒ Object

Fetches an attribute of an object using hash notation

Parameters:

  • method (String, Symbol) —

    Message to send to the object



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# File 'lib/wayback/base.rb', line 86

def [](method)
  send(method.to_sym)
rescue NoMethodError
  nil
end

#attr_equal(attr, other) ⇒ Boolean (protected)

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/wayback/base.rb', line 116

def attr_equal(attr, other)
  self.class == other.class && !other.send(attr).nil? && send(attr) == other.send(attr)
end

#attrs ⇒ Hash Also known as: to_hash

Retrieve the attributes of an object

Returns:

  • (Hash) 


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# File 'lib/wayback/base.rb', line 95

def attrs
  @attrs.inject({}) do |attrs, (key, value)|
    attrs.merge!(key => respond_to?(key) ? send(key) : value)
  end
end

#attrs_equal(other) ⇒ Boolean (protected)

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/wayback/base.rb', line 122

def attrs_equal(other)
  self.class == other.class && !other.attrs.empty? && attrs == other.attrs
end

#update(attrs) ⇒ Wayback::Base

Update the attributes of an object

Parameters:

  • attrs (Hash)

Returns:



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# File 'lib/wayback/base.rb', line 106

def update(attrs)
  @attrs.update(attrs)
  self
end