Module: Hasherizer

Defined in:
lib/hasherizer.rb

Overview

Makes a hash out of an object recursively.

Class Method Summary collapse

Class Method Details

.to_hash(object) ⇒ Hash

Extract instance variables names and values into a flat hash no matter how many levels deep your objects are.

Parameters:

  • -- (Object, #read) —

    Object which instance variables are to be converted to a hash.

Returns:

  • (Hash) —

    /[Object] – A hash or an object.



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# File 'lib/hasherizer.rb', line 8

def self.to_hash(object)
  # Check if object has hash behavior. Check before :each because hashes also respond to :each.
  if object.respond_to? :to_hash
    object
  # Check if object has array behavior.
  elsif object.respond_to? :each
    # If all elements have hash behavior, return them in a flat hash.
    if object.all? {|element| element.respond_to? :to_hash}
      hash = {}
      object.each {|element| hash.merge! element}
      hash
    # If all elements have instance variables, process each element.
    elsif object.all? {|element| element.instance_variables.size > 0}
      hash = {}
      object.each {|element| hash.merge! to_hash(element)}
      hash
    # Otherwise return the object/value.
    else
      object
    end
  # If no hash nor array, its either an object with instance variables or a value.
  else
    # Get object's instance variables.
    instance_vars = object.instance_variables.collect {|var| var[1..-1]}

    # If no instance variables, return object/value.
    if instance_vars.size.zero?
      object
    # If instance variables, process them.
    else
      hash = {}

      instance_vars.each do |var|
        resp = to_hash(object.instance_eval(var))

        # If instance variable has hash behavior add it to the returned hash values.
        if resp.respond_to? :to_hash
          hash.merge! resp
        # If instance variable does not have hash behavior, create hash entry for the variable name and its value.
        else
          hash.merge! var => resp
        end
      end

      hash
    end
  end
end