AWS Record Rails Generators have been moved to aws-sdk-rails

This feature has been moved to aws-sdk-rails.

This documentation will remain for historical purposes.

Allows the generation of aws-record models using a Rails generator

• aws-record Documentation
• DynamoDB Developers Guide

You can install the gem from RubyGems using the --pre flag gem install 'aws-record-generator' --pre

This automatically includes a dependency on the aws-record gem, major version 2, as well as a dependency on >= Rails v4.2

You can either invoke the generator by calling rails g aws_record:model ...

If DynamoDB will be the only datastore you plan on using you can also set aws-record-generator to be your project's default orm with

config.generators do |g|
  g.orm             :aws_record
end

Which will cause aws_record:model to be invoked by the Rails model generator.

Generating a model can be as simple as: rails g aws_record:model Forum --table-config primary:10-5 aws-record-generator will automatically create a uuid:hash_key field for you, and a table config with the provided r/w units

# app/models/forum.rb

require 'aws-record'

class Forum
  include Aws::Record

  string_attr :uuid, hash_key: true
end

# db/table_config/forum_config.rb

require 'aws-record'

module ModelTableConfig
  def self.config
    Aws::Record::TableConfig.define do |t|
      t.model_class Forum

      t.read_capacity_units 10
      t.write_capacity_units 5
    end
  end
end

More complex models can be created by adding more fields to the model as well as other options:

rails g aws_record Forum post_id:rkey author_username post_title post_body tags:sset:default_value{Set.new}

# app/models/forum.rb

require 'aws-record'

class Forum
  include Aws::Record

  string_attr :uuid, hash_key: true
  string_attr :post_id, range_key: true
  string_attr :author_username
  string_attr :post_title
  string_attr :post_body
  string_set_attr :tags, default_value: Set.new
end

# db/table_config/forum_config.rb
# ...

Finally you can attach a variety of options to your fields, and even ActiveModel validations to the models:

rails g aws_record:model Forum forum_uuid:hkey post_id:rkey author_username post_title post_body tags:sset:default_value{Set.new} created_at:datetime:db_attr_name{PostCreatedAtTime} moderation:boolean:default_value{false} --table-config=primary:5-2 AuthorIndex:12-14 --required=post_title --length-validations=post_body:50-1000 --gsi=AuthorIndex:hkey{author_username}

Which results in the following files being generated:

# app/models/forum.rb

require 'aws-record'
require 'active_model'

class Forum
  include Aws::Record
  include ActiveModel::Validations

  string_attr :forum_uuid, hash_key: true
  string_attr :post_id, range_key: true
  string_attr :author_username
  string_attr :post_title
  string_attr :post_body
  string_set_attr :tags, default_value: Set.new
  datetime_attr :created_at, database_attribute_name: "PostCreatedAtTime"
  boolean_attr :moderation, default_value: false

  global_secondary_index(
    :AuthorIndex,
    hash_key: :author_username,
    projection: {
      projection_type: "ALL"
    }
  )
  validates_presence_of :post_title
  validates_length_of :post_body, within: 50..1000
end

# db/table_config/forum_config.rb
# ...

To migrate your new models and begin using them you can run the provided rake task: rails aws_record:migrate

If you invoke aws_record:scaffold instead of aws_record:model then the generator will construct a full controller-view-model structure.

The syntax for creating an aws-record model follows:

rails generate aws_record:model NAME [field[:type][:opts]...] [options]

The possible field types are:

If a type is not provided aws-record-generator will assume the field is of type :string_attr

Additionally a number of options may be attached as a comma seperated list to the field:

The standard rules apply for using options in a model. Additional reading can be found here

The included rake task aws_record:migrate will run all of the migrations in app/db/table_config

This library is licensed under the Apache 2.0 License.