Knuckles (Because Sonic was Taken)

Knuckles is a performance focused data serialization pipeline. More simply, it tries to serialize models into large JSON payloads as quickly as possible.

What's it all about?

• Emphasis on caching as a composable operation
• Reduced object instantiation
• Complete instrumentation of every discrete operation
• Entirely agnostic, can be dropped into any project and integrated over time
• Minimal runtime dependencies
• Explicit serializer view API with as little overhead and no DSL

Is It Better?

Knuckles is absolutely faster and has a lower memory overhead than uncached or cached usage of ActiveModelSerializers, and significantly faster than cached use of ActiveModelSerializers with the perforated gem.

Here are performance and memory comparisons for an endpoint that has been cached with Perforated and with Knuckles. All measurments were done with production settings over the local network.

	average	longest	shortest	allocated	retained
perforated/ams	230ms	560ms	190ms	148,735	18,203
knuckles/ams	30ms	60ms	20ms	19,603	136

These are measurements for a sizable payload with hundreds of associated records.

Installation

Add this line to your application's Gemfile:

gem "knuckles"

Configuration

There isn't a hard dependency on Oj or Readthis, but you'll find they are drastically more performant.

require "activesupport"
require "oj"
require "readthis"

Knuckles.configure do |config|
  config.cache = Readthis::Cache.new(
    marshal: Oj,
    compress: true,
    driver: :hiredis
  )

  config.keygen = Readthis::Expanders
  config.serializer = Oj
end

With the top level module configured it is simple to jump right into rendering, but we'll look at configuring the pipeline first.

Defining Views for Rendering

While you can use Knuckles with other serializers, you can also use the provided view layer. Knuckles views are simple templates that let you build up data and relations. They look like this:

module ScoutView
  extend Knuckles::View

  def self.root
    :scouts
  end

  def self.data(object, options)
    {id: object.id, email: object.email, name: object.name}
  end

  def self.relations(object, options)
    {things: has_many(object.things, ThingView)}
  end
end

See Knuckles::View for more usage details.

Contributing

1. Fork it ( https://github.com/sorentwo/knuckles/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