= GoldRecord

Unobtrusive binary UUIDs for ActiveRecord.

• http://github.com/ydnar/gold-record
• http://gemcutter.org/gems/gold-record
• mailto:[email protected]

== DESCRIPTION

GoldRecord is an extension for ActiveRecord that implements unobtrusive binary UUIDs[http://en.wikipedia.org/wiki/Universally_Unique_Identifier] in MySQL.

== FEATURES

GoldRecord supports SchemaDumper by not declaring the id column a PRIMARY KEY. The odds of a random UUID collision are documented here[http://en.wikipedia.org/wiki/Universally_Unique_Identifier#Random_UUID_probability_of_duplicates].

• Uses space-efficient 16-byte binary representation for UUIDs.
• Works with associations, migrations and ActiveRecord::SchemaDumper.
• Transparently converts to hex-encoded UUIDs in #to_param.
• Transparently handles binary, hex-encoded and URL-safe Base64 UUIDs in #find.

== SYNOPSIS

class Blog < ActiveRecord::Base acts_as_gold_record has_many :posts end

class Post < ActiveRecord::Base acts_as_gold_record end

=== Or, for the exceptionally paranoid:

class LargeHadron < ActiveRecord::Base acts_as_gold_record set_primary_key :lottery_number validates_uniqueness_of :lottery_number, :on => :create end

== FIXTURES

In test/helper.rb or spec_helper.rb:

require 'active_record/fixtures' Fixtures.send :include, GoldRecord::Fixtures

== MIGRATIONS

class MakeGoldRecords < ActiveRecord::Migration TABLES = [:labels, :record_stores] ASSOCIATIONS = [ [:artists, :label_id, :id], [:labels_record_stores, :label_id, false], [:labels_record_stores, :record_store_id, false], [:artists_record_stores, :record_store_id, false], ]

def self.up
  # Change each int(11) id column to binary(16).
  # This preserves the column’s original value as a right-padded 16-byte string.
  TABLES.each do |table|
    change_integer_primary_key_to_uuid(table)
    add_index table, :id
  end

  # Change association columns to binary(16).
  ASSOCIATIONS.each do |table, column, primary_key|
    change_integer_to_uuid(table, column, primary_key)
  end
end

# Down migration designed to be run immediately after an up migration
# in the event of some failure. Running this after generating any UUIDs
# will produce unpredictable results.

def self.down
  # Change each binary(16) id column to int(11).
  # MySQL casts the string value to an integer.
  TABLES.each do |table|
    remove_index table, :id
    change_uuid_to_integer_primary_key(table)
  end

  # Change association columns to int(11).
  ASSOCIATIONS.each do |table, column|
    change_uuid_to_integer(table, column, primary_key)
  end
end

end

== INSTALL

=== As a gem:

[sudo] gem install gold-record

=== As a Rails plugin:

Clone/copy to vendor/plugins/gold_record.