mongodb - mongoid configuration on ruby without framework -

i try write business logic of application. ruby classes. there no database or no ui framework rails, sinatra. have gem_file on business logic and, gem_file contain "mini_test" gem. use mini_test testing business logic. now, need add database system. how can this? mongoid configuration made in application.file on rails. ,i don't use rails or other framework. there anyway make configuration of mongoid without framework rails, sinatra. hope can explain problem. also, add codes in below:

this context-

class headteacherdefineacademicyearcontext   attr_reader :person, :academicyear    def initialize(person, academicyear)     @person, @academicyear = person, academicyear     @person.extend headteacher   end    def call    @person.define_academic_year @academicyear   end end 

this role module

module headteacher   def define_academic_year(academicyear)      #i write db save process here using database   end end 

my model class

class academicyear   attr_accessor :year end 

you have include gem 'mongoid' in gemfile , install it. after that, can require , initialize mongoid need it:

require 'mongoid' mongoid.load!("mongoid.yml", :development) 

it expects mongoid.yml file configuration. examlpe:

development:    sessions:      default:       database: myapp_development       hosts:         - localhost:27017 

of course, can use context :development, maybe assign via environment variable. now, add mongoid::document model:

class academicyear   include mongoid::document    field :year, type: integer end