LinkToMe

⚠️ Guess what?! You no longer need link_to_me if you use Rails 7.0.x or newer, it was merged in as a feature on September 21st, 2021!

As a consequence I will no longer be maintaining this gem, but feel free to use try it in older versions of Rails but please note I haven't tested it on any version prior to Rails 7, and it therefore may not be compatible.

Extend Rails Action View's link_to to allow it to autolink any Active Record model instances with a GET url.

Installation

Add this line to your application's Gemfile:

gem 'link_to_me'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install link_to_me

Usage

Instead of having the write the oddly repetitive:

link_to @model.name, @model

Or if you have a to_s method on Model already, the still silly:

link_to @model, @model

You can now write:

link_to @model

Which will result in the following code:

<a href="/models/1">Model 1</a>

Given the @model instance's class Model defines the following method:

class Model
  def to_s
    "Model #{id}"
  end
end

Here, to_s can point to an attribute like name as well if it exists and use a fallback:

class Model
  def to_s
    name || "Model #{id}"
  end
end

If you don't implement a to_s method, link_to will instead default to the original Ruby definition of to_s which prints the name of the instance's class and its object_id in hexacidemal format:

Object.new.to_s
=> "#<Object:0x00007fc122ad4d10>"

It's not quite as useful. Defining to_s on Rails Active Record model classes is not at all destructive. You can still obtain the non-hexadecimal memory object ID via Object.new.object_id:

Object.new.object_id
=> 109720

How does it work?

LinkToMe uses a Railtie to hook into the boot process for Action View and include itself inside of ActionView::Helpers::UrlHelper. Using the self.included hook, it aliases the existing link_to method to _rails_link_to and then removes the link_to method so that its own slightly different link_to method can take over.

The core of the logic simply checks whether the first parameter to link_to (which is usually a string) responds to the model_name method, which indicates that it's an Active Record model instance. It also checks whether there are other arguments provided, which would indicate link_to is being given a specific path.

This means you can still override the inferred path even if you decide to use link_to's ability (via url_for) to infer a given active record model instance's name.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec 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 https://github.com/olivierlacan/link_to_me. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the LinkToMe project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.