require 'lotus/utils/hash' module Lotus module Utils # A set of attributes. # # It internally stores the data as a Hash. # # All the operations convert keys to strings. # This strategy avoids memory attacks due to Symbol abuses when parsing # untrusted input. # # At the same time, this allows to get/set data with the original key or # with the string representation. See the examples below. # # @since 0.3.2 class Attributes # Initialize a set of attributes # All the keys of the given Hash are recursively converted to strings. # # @param hash [#to_h] a Hash or any object that implements #to_h # # @return [Lotus::Utils::Attributes] self # # @since 0.3.2 # # @example # require 'lotus/utils/attributes' # # attributes = Lotus::Utils::Attributes.new(a: 1, b: { 2 => [3, 4] }) # attributes.to_h # => { "a" => 1, "b" => { "2" => [3, 4] } } def initialize(hash = {}) @attributes = Utils::Hash.new(hash, &nil).stringify! end # Get the value associated with the given attribute # # @param attribute [#to_s] a String or any object that implements #to_s # # @return [Object,NilClass] the associated value, if present # # @since 0.3.2 # # @example # require 'lotus/utils/attributes' # # attributes = Lotus::Utils::Attributes.new(a: 1, 'b' => 2, 23 => 'foo') # # attributes.get(:a) # => 1 # attributes.get('a') # => 1 # attributes[:a] # => 1 # attributes['a'] # => 1 # # attributes.get(:b) # => 2 # attributes.get('b') # => 2 # attributes[:b] # => 2 # attributes['b'] # => 2 # # attributes.get(23) # => "foo" # attributes.get('23') # => "foo" # attributes[23] # => "foo" # attributes['23'] # => "foo" # # attributes.get(:unknown) # => nil # attributes.get('unknown') # => nil # attributes[:unknown] # => nil # attributes['unknown'] # => nil def get(attribute) @attributes[attribute.to_s] end # @since 0.3.4 alias_method :[], :get # Set the given value for the given attribute # # @param attribute [#to_s] a String or any object that implements #to_s # @param value [Object] any value # # @return [NilClass] # # @since 0.3.2 # # @example # require 'lotus/utils/attributes' # # attributes = Lotus::Utils::Attributes.new # # attributes.set(:a, 1) # attributes.get(:a) # => 1 # attributes.get('a') # => 1 # # attributes.set('b', 2) # attributes.get(:b) # => 2 # attributes.get('b') # => 2 # # attributes.set(23, 'foo') # attributes.get(23) # => "foo" # attributes.get('23') # => "foo" def set(attribute, value) @attributes[attribute.to_s] = value nil end # Returns a deep duplicated copy of the attributes as a Hash # # @return [::Hash] # # @since 0.3.2 def to_h ::Hash[].tap do |result| @attributes.each do |k, v| result[k] = _read_value(v) end end end private # @since 0.4.1 # @api private def _read_value(value) case val = value when ::Hash, ::Lotus::Utils::Hash, ->(v) { v.respond_to?(:lotus_nested_attributes?) } val.to_h else val end end end end end