Class: Appetizer::Populator

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

Overview

Helps assign values from a low-level structure to a rich domain model. Most useful as an explicit alternative to ActiveRecord’s mass-assignment, with an AR object as the target and a params hash as the source.

Defined Under Namespace

Modules: Helpers

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(target, source) {|_self| ... } ⇒ Populator

Returns a new instance of Populator.

Yields:

  • (_self)

Yield Parameters:



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# File 'lib/appetizer/populator.rb', line 12

def initialize target, source, &block
  @target = target
  @source = source

  yield self if block_given?
end

Instance Attribute Details

#source ⇒ Object (readonly)

Returns the value of attribute source.



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# File 'lib/appetizer/populator.rb', line 10

def source
  @source
end

#target ⇒ Object (readonly)

Returns the value of attribute target.



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# File 'lib/appetizer/populator.rb', line 9

def target
  @target
end

Instance Method Details

#nested(key, target = nil, &block) ⇒ Object 



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# File 'lib/appetizer/populator.rb', line 19

def nested key, target = nil, &block
  source   = self.source[key] || self.source[key.intern]
  target ||= self.target.send key

  Populator.new target, source, &block if source
end

#set(key, value = nil) ⇒ Object 



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# File 'lib/appetizer/populator.rb', line 26

def set key, value = nil
  value ||= source[key] || source[key.intern]

  return if value.nil? || (value.respond_to?(:empty?) && value.empty?)
  set! key, value
end

#set!(key, value, &block) ⇒ Object 



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# File 'lib/appetizer/populator.rb', line 33

def set! key, value, &block
  block ? block[value] : target.send("#{key}=", value)
end