ActiveRecord::UUID

Override migration methods to support UUID columns without having to be explicit about it.

What this gem will do for you:

• When creating new tables, will set the id column as uuid.
• When creating associations with t.belongs_to, t.references or add_reference, will set the column type as uuid.

Installation

Add this line to your application's Gemfile:

gem "ar-uuid"

And then execute:

$ bundle

Or install it yourself as:

$ gem install ar-uuid

Usage

There's no setup. Just adding the gem to your Gemfile is enough. When you create a new table, the id column will be defined as uuid. This is also true for references.

create_table :users
add_reference :posts, :users

create_table :posts do |t|
  t.belongs_to :user
  # or
  t.references :user
end

If you need a serial column, AR's PostgreSQL supports the bigserial column type.

create_table :users do |t|
  t.column :position, :bigserial, null: false
end

Disadvantages

There is one big disadvantage on using uuid identifiers: you can't use methods like ActiveRecord::FinderMethods::InstanceMethods#first and ActiveRecord::FinderMethods::InstanceMethods#last, since they are scoped to the sequential id.

The easiest alternative is ordering results and calling first/last. You can either create a sequence, or use the created_at/updated_at columns:

# Get first record
User.order(created_at: :asc).first

# Get last record
User.order(created_at: :desc).first

# Use scopes
class User < ApplicationRecord
  scope :newer, -> { order(created_at: :desc) }
  scope :older, -> { order(created_at: :asc) }
end

User.older.first
User.newer.first

You can also replace .first with ActiveRecord::FinderMethods::InstanceMethods#take, which will use the order implemented by the database.

There's no alternative to .last.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment. 4 To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release to create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

1. Fork it ( https://github.com/fnando/ar-uuid/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