Surrealist gem extension

hash_based.rb

class HashBased
  include Surrealist
  extend Schema

  attr_reader :hash

  def initialize(hash = {})
    @hash = hash.deep_symbolize_keys
  end

  def method_missing(method_name, *args)
    if hash.key?(method_name)
      hash[method_name]
    else
      super
    end
  end

  def respond_to_missing?(method_name, _include_private = false)
    hash.key?(method_name)
  end
  
  # Add support to `present` method from Grape
  def self.represent(data, _context)
    new(data).surrealize
  end
end

my_serializer.rb

class MySerializer < HashBased
  json_schema do
    { name: String, age: Integer }
  end
end

# useful to test the schema for instance.. expect(MySerializer.defined_schema).to eq(...)
MySerializer.defined_schema # { name: String, age: Integer }
# generate mock for your tests for instance..
MySerializer.schema_sample # { name: "", age: 0 } 

schema.rb

module Schema
  def defined_schema
    instance_variable_get('@__surrealist_schema')
  end

  def schema_sample
    recursive(defined_schema)
  end

  private

  def recursive(hash, final = {})
    hash.each do |key, value|
      final[key] = if value.is_a?(Hash)
        recursive(value, {})
      else
        value_for_type(value)
      end
    end
    final
  end

  def value_for_type(value)
    if value == Integer
      0
    elsif value == String
      ''
    elsif value == Bool
      false
    else
      nil
    end
  end
end