OptimisticallyStale

:small_blue_diamond: micro gem to validate updatability enforcing optimistic locking using +lock_version`, before you hit the Database.

Installation

Add this line to your application's Gemfile:

gem 'optimistically_stale'

And then execute:

$ bundle

Or install it yourself as:

$ gem install optimistically_stale

Usage

# @example Check a record before updating
class UpdateBook
  include Command

  def call(book:, attributes:)
    book.update(attributes)
  end

  def valid?(book:, attributes:)
    valid_for_update?(record: :book, attributes: attributes)
  end
end

# ...

book = Book.first
attributes = { lock_version: book.lock_version, title: 'new book title' }
result = UpdateBook.call(book: book, attributes: attributes)

result.successful? # => true
book.title # => 'new book title'

# @example Because the book version has changed, another update fails
attributes[:title] = 'another title'
result = UpdateBook.call(book: book, attributes: attributes)
# => throws ActiveRecord::StaleObjectError

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

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, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at XPBytes/optimistically_stale.