Typhoeus Arrays decoding in Rails

application_controller.rb

require 'typhoeus/arrays_decoder'

class ApplicationController < ActionController::Base
  protect_from_forgery

  before_filter :decode_typhoeus_arrays

  private

  def decode_typhoeus_arrays
    deep_decode(params)
  end

  # Recursively decode Typhoeus encoded arrays
  def deep_decode(hash)
    return hash unless hash.is_a?(Hash)
    hash.each_pair do |key,value|
      if value.is_a?(Hash)
        deep_decode(value)
        hash[key] = value.decode_typhoeus_array
      end
    end
  end
end

arrays_decoder.rb

# Rack Middleware to fix Typhoeus arrays encoding
=begin
module Typhoeus
  class ArraysDecoder
    def initialize(app)
      @app = app
    end

    def call(env)
      TODO this solution didn't work, when fixed remove filter from ApplicationController
      params = env["action_dispatch.request.parameters"]
      decode_typho_arrays(params)
      env["action_dispatch.request.parameters"] = params
      @app.call(env)
    end

    private

    # Recursively decode Typhoeus encoded arrays
    def decode_typho_arrays(hash)
      return hash unless hash.is_a?(Hash)
      hash.each_pair do |key,value|
        if value.is_a?(Hash)
          decode_typho_arrays(value)
          hash[key] = value.decode_typhoeus_array
        end
      end
    end
  end
end
=end

# Add Hash#is_typhoeus_array? method
class Hash

  # Checks if hash is an Array encoded as a hash.
  # Specifically will check for the hash to have this form: {'0' => v0, '1' => v1, .., 'n' => vN }
  # @return [TrueClass]
  def im_an_array_typhoeus_encoded?
    return false if self.empty?
    self.keys.sort == (0...self.keys.size).map{|i|i.to_s}
  end

  # If the hash is an array encoded by typhoeus an array is returned
  # else the self is returned
  #
  # @see im_an_array_typhoeus_encoded?
  #
  # @return [Array/Hash]
  def decode_typhoeus_array
    if self.im_an_array_typhoeus_encoded?
      Hash[self.sort].values
    else
      self
    end
  end
end