mongo_mapper + database.yml

database.yml

development: &default_settings
  database: APPNAME_development
  host: 127.0.0.1
  port: 27017

test:
  <<: *default_settings
  database: APPNAME_test

production:
  <<: *default_settings
  database: APPNAME_production
  # host: hostname
  # username: username
  # password: password

mongo_database.rb

config = YAML.load_file("#{Rails.root}/config/database.yml")[Rails.env]

MongoMapper.connection = Mongo::Connection.new(config['host'], config['port'], {
  :logger => Rails.logger
})

MongoMapper.database = config['database']
if config['username'].present?
  MongoMapper.database.authenticate(config['username'], config['password'])
end

Dir["#{Rails.root}/app/models/**/*.rb"].each do |model_path|
  File.basename(model_path, '.rb').classify.constantize
end
MongoMapper.ensure_indexes!

if defined?(PhusionPassenger)
  PhusionPassenger.on_event(:starting_worker_process) do |forked|
    MongoMapper.database.connect_to_master if forked
  end
end