DynamoRecord

A simple DynamoDB ORM container on aws-sdk v3 forked from https://github.com/yetanothernguyen/dynamo_record

Installation

Add this line to your application's Gemfile:

gem 'dynamodb_record'

And then execute:

$ bundle

Or install it yourself as:

$ gem install dynamodb_record

Usage

Models

To create a model with DynamoRecord, simply include the DynamoRecord::Document mixin in your class as such::

class User
  include DynamoRecord::Document
end

Fields

Declaring a field is done by using the field method. For example, the following defines a User model with a first and last name:

class User
  include DynamoRecord::Document

  field :first_name, :string
  field :last_name, :string
end

field accepts the following options:

  • :default to specify a default value
  • :hash_key to specify a DynamoDB hash key
  • :range_key to specify a DynamoDB range key
  • :index to specify an index

Persistence

DynamoRecord provides a similar persistence interface compared to other ORMs.

user = User.new(first_name: 'John', last_name: 'Doe')
user.save

user = User.create(first_name: 'John', last_name: 'Doe')

user.destroy

Querying

users = User.all

users = User.where(first_name: 'John')

users = User.where(first_name: 'John', limit: 5)

user = User.find('f9b351b0-d06d-4fff-b8d4-8af162e2b8ba')

With error

User.find!('f9b351b0-d06d-4fff-b8d4-8af162e2b8ba')

The has_many Association

Associations are placed in their respective classes

car.rb

class Car
  include DynamodbRecord::Document

  field :marca, :string
  has_many :insurances
end

insurance.rb

class Insurance
  include DynamodbRecord::Document

  field :name, :string
  field :car_id, :string, index: true
  belongs_to :car
end

There are many ways to generate associations:

'<<' method

# Find a car with ID 'UVX123'
car = Car.find('UVX123')

# Create a new insurance instance
insurance = Insurance.new(name: 'Bolivar')

# Associate the insurance with the car
car.insurances << insurance

Contributing

  1. Fork it ( https://github.com/[my-github-username]/dynamo_record/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request