Hashid Rails

This gem allows you to easily use Hashids in your Rails app. Instead of your models using sequential numbers like 1, 2, 3, they will instead have unique short hashes like "yLA6m0oM", "5bAyD0LO", and "wz3MZ49l". The database will still use integers under the hood, so this gem can be added or removed at any time.

Installation

Add this line to your application's Gemfile:

gem 'hashid-rails'

And then execute:

$ bundle

Or install it yourself as:

$ gem install hashid-rails

Basic Usage

Just use Model#find passing in the hashid instead of the model id.

@person = Person.find(params[:hashid])

Alternative Usage

You can use the Model#find_by_hashid method to find a record without falling back on the standard find method. This can be useful in cases where the hashid might be misinterpreted by the find method, such as using a hashid containing only numbers that could be both interpreted as either an id and or a hashid.

# When a record is found, it returns the record.
@person = Person.find_by_hashid(params[:hashid])

# When no record, is found it raises an exception.
ActiveRecord::RecordNotFound

Configuration

To customize the Hashids seed and ensure that another user of the gem cannot easily reverse engineer your ids, create an initializer and:

Hashid::Rails.configure do |config|
  config.secret = 'my secret'
  config.length = 6
  # config.alphabet is optional, hashids provides a default
  # alphabet that consists of all characters [a-zA-Z0-9]
  config.alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

  # If your alphbet contains any numerals [0-9], then we recommend diabling the find method
  #config.disable_find = true
end

Disable Find Method

If your alphabet includes numerals (0-9) and if the ids in your database are the same length as your hashes, then there could be valid hashids that are identical to valid ids. This ambiguity could lead the find method to behave unpredictably. Since find accepts both hashids and ids, an input argument that is potentially both a valid hashid and id, will cause find to treat the argument as a hashid in some cases, and as an id in others. This unpredictably is usually not desired and can lead to subtle bugs appearing at runtime

In order to avoid this problem, users can add config.disable_find = true to their initializer. This will disable the hashid functionality of the find method and force find to only accept normal (unhashed) ids. Under this configuration, programmer will need to use the find_by_hashid method when desiring to explicitly search by hashid.

It is recommended that config.disable_find = true be set when the alphabet contains any numerals.

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.

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/[my-github-username]/hashid-rails/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