Snorlax

Snorlax is an opinionated, flexible, and well-RESTed gem for building Rails APIs. It's designed to Do The Right Thing™ by default, but allow you to customize where necessary.

It's been extracted from Loomio.

Installation

Add this line to your application's Gemfile:

gem 'snorlax'

And then execute:

$ bundle

Or install it yourself as:

$ gem install snorlax

Usage

There are two primary ways to use Snorlax. The easier way is to inherit from it:

class MyController < Snorlax::Base
end

But, if you're already inheriting from something else, Snorlax makes it easy to simply apply itself to your controller without being a parent, by calling snorlax_used_rest! like so:

class MyController < SomeOtherController
  snorlax_used_rest!
end

Once you've got it installed, you're good to go!

Some things to know about Snorlax:

Side loading

Snorlax is designed to provide a set of flexible API endpoints for client side consumption. It uses side loading, which means that all of the records returned are unnested and easily available for consumption.

The show action

By default, Snorlax will fetch the requested model by id using the ActiveModel::Base.find method. To override this behaviour, you may override the load_resource method in your controller.

NB: This would be a great place to ensure that the current user is allowed to view the requested resource.

The index action

Snorlax DEMANDS that you define two separate methods for the index action to work properly:

• public_records - records which are available publicly (ie, they can be viewed even if current_user is nil)
• visible_recordss - records which the current user is allowed to access.

class StaryusController < Snorlax::Base
  def public_records
    Staryu.visible_to_public
  end

  def visible_records
    current_user.staryus
  end
end

If these are the same, you may override the accessible_records method instead

class StarmiesController < Snorlax::Base
  def accessible_records
    Starmie.all
  end
end

Paging the index action

A Snorlax controller can accept from and per parameters for paging. For example,

/api/vi/psyducks?from=0&per=100

will return the first 100 psyducks within the acccessible records.

If no from or per params are provided, Snorlax will default to the first 50 records. (from = 0, per = 50)

You can override the default page size by overriding the default_page_size method.

class WobbuffetsController < Snorlax::Base
  def default_page_size
    25
  end
end

Timeframing the index action

A Snorlax controller can accept since and until parameters for timeframing. The date it looks for defaults to created_at. For example,

/api/v1/charmanders?since=11-11-2011&until=12-12-2012

will return charmanders which were created between Nov 11, 2011, and Dec 12, 2012.

You can override the datetime column the query looks at by passing the timeframe_for option. For example,

/api/v1/charmeleons?since=11-11-2011&until=12-12-2012&timeframe_for=evolved_at

will return charmeleons which evolved between Nov 11, 2011, and Dec 12, 2012

Since and until can be in any format that Date.parse will accept.

Custom filtering on the index action

Snorlax also provides a dead simple way to provide your own filters, in addition to and in combination with the ones provided. You can do this by passing a block to the instantiate_collection method in your controller action. For example,

class ChanseysController < Snorlax::Base
  def sleeping
    instantiate_collection { |collection| collection.where(sleeping: true) }
    respond_with_collection
  end
end

Will return all sleeping Chanseys. (This can be combined with timeframing and paginating as well.) (NB: this filtering happens before the collection is paginated or timeframed, so it's a good opportunity to add additional filters or apply an order to your records. Or both!)

TODO

• Customizing the serializer options
• Expand on create / update action
  • create_action, update_action overriding
  • respond_with_resource
• Expand on destroy action [destroy_action]
  • destroy_action overriding
• Explain the respond_with_errors behaviour

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/gdpelican/snorlax. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

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