FrozenRecord

ActiveRecord-like interface for read only access to YAML static data.

Installation

Add this line to your application's Gemfile:

gem 'frozen_record'

And then execute:

$ bundle

Or install it yourself as:

$ gem install frozen_record

Models definition

Just like with ActiveRecord, your models need to inherits from FrozenRecord::Base:

class Country < FrozenRecord::Base
end

But you also have to specify in which directory your data files are located. You can either do it globaly

FrozenRecord::Base.base_path = '/path/to/some/directory'

Or per model:

class Country < FrozenRecord::Base
  self.base_path = '/path/to/some/directory'
end

Query interface

FrozenRecord aim to replicate only modern ActiveRecord querying interface, and only the non "string typed" ones.

e.g

# Supported query interfaces
Country.
  where(region: 'Europe').
  where.not(language: 'English').
  order(id: :desc).
  limit(10).
  offset(2).
  pluck(:name)

# Non supported query interfaces
Country.
  where('region = "Europe" AND language != "English"').
  order('id DESC')

Scopes

While the scope :symbol, lambda syntax is not supported, the class methods way is:

class Country
  def self.republics
    where(king: nil)
  end

  def self.part_of_nato
    where(nato: true)
  end
end

Country.republics.part_of_nato.order(id: :desc)

Supported query methods

• where
• where.not
• order
• limit
• offset

Supported finder methods

• find
• first
• last
• to_a
• exists?

Supported calculation methods

• count
• pluck
• ids
• minimum
• maximum
• sum
• average

Configuration

Reloading

By default the YAML files are parsed once and then cached in memory. But in development you might want changes to be reflected without having to restart your application.

For such cases you can set auto_reloading to true either globally or on a model basis:

FrozenRecord::Base.auto_reloading = true # Activate reloading for all models
Country.auto_reloading # Activate reloading for `Country` only

Contributors

FrozenRecord is a from scratch reimplementation of a Shopify project from 2007 named YamlRecord. So thanks to:

• John Duff - @jduff
• Dennis O'Connor - @dennisoconnor
• Christopher Saunders - @csaunders
• Jonathan Rudenberg - @titanous
• Jesse Storimer - @jstorimer
• Cody Fauser - @codyfauser
• Tobias Lütke - @tobi