How to implement an Mongoid Document like class? - ruby

Question

I'm building a small script where I'd need to implement a Mongoid Document like class, where I include my base module and then I can build a class which looks like:
class MyClass
include MyBaseModule
field :some_field, :attr => 'attributes'
end
This is my last try:
module Model
def initialize(keys = {})
puts ##keys
end
def method_missing sym, *args
if sym =~ /^(\w+)=$/
if ##keys.has_key?($1)
##keys[$1.to_sym] = args[0]
else
nil
end
else
if ##keys.has_key?($1)
##keys[sym.to_sym]
else
nil
end
end
end
def inspect
puts "#<#{self.class} #keys=#{##keys.each {|k,v| "#{k} => #{v}"}}>"
end
def self.included(base)
base.extend(ClassMethods)
end
def save
##keys.each do |k, v|
SimpleMongo::connection.collection.insert({k => v})
end
end
module ClassMethods
def field(name, args)
if ##keys.nil?
##keys = {}
end
##keys[name.to_sym] = default_value
end
end
end
Mongoid documents look like this:
class StoredFile
include Mongoid::Document
field :name, type: String
field :description, type: String
field :password, type: String
field :public, type: Boolean
field :shortlink, type: String
mount_uploader :stored_file, StoredFileUploader
before_save :gen_shortlink
before_save :hash_password
belongs_to :user
def gen_shortlink
self.shortlink = rand(36**10).to_s(36)
end
def public?
self.public
end
def hash_password
require 'bcrypt'
self.password = BCrypt::Password.create(self.password).to_s
end
def check_pass(password)
BCrypt::Password.new(self.password) == password
end
end
It doesn't works because the ##keys variable inside ClassMethods isn't available anywhere outside that module. What would be the easiest way to implement this? Thanks!

Answer 1

The easiest way to implement it would be to have a class variable getter.
module Model
def self.included(base)
base.extend(ClassMethods)
end
module ClassMethods
def keys
#keys ||= {}
end
def field(name, opts)
#keys ||= {}
#keys[name] = opts
end
end
def initialize(attributes)
# stuff
puts self.class.keys
end
end