Spyke

Interact with remote REST services in an ActiveRecord-like manner.

---

Spyke basically ~~rips off~~ takes inspiration :innocent: from Her, a gem which we sadly had to abandon as it gave us some performance problems and maintenance seemed to have gone stale.

We therefore made Spyke which adds a few fixes/features needed for our projects:

• Fast handling of even large amounts of JSON
• Proper support for scopes
• Ability to define custom URIs for associations
• ActiveRecord-like log output
• Googlable name! :)

Configuration

Add this line to your application's Gemfile:

gem 'spyke'

Like Her, Spyke uses Faraday to handle requests and expects it to return a hash in the following format:

{ data: { id: 1, name: 'Bob' }, metadata: {}, errors: [] }

The simplest possible configuration that can work is something like this:

# config/initializers/spyke.rb

class JSONParser < Faraday::Response::Middleware
  def parse(body)
    json = MultiJson.load(body, symbolize_keys: true)
    {
      data: json[:result],
      metadata: json[:metadata],
      errors: [json[:message]]
    }
  rescue MultiJson::ParseError => exception
    { errors: [exception.cause] }
  end
end

Spyke::Config.connection = Faraday.new(url: 'http://api.com') do |c|
  c.request   :json
  c.use       JSONParser
  c.adapter   Faraday.default_adapter
end

Usage

Adding a class and inheriting from Spyke::Base will allow you to interact with the remote service:

class User < Spyke::Base
  has_many :posts

  scope :active, -> { where(active: true) }
end

User.all
# => GET http://api.com/users

User.active
# => GET http://api.com/users?active=true

User.where(age: 3).active
# => GET http://api.com/users?active=true&age=3

user = User.find(3)
# => GET http://api.com/users/3

user.posts
# => find embedded in returned JSON or GET http://api.com/users/3/posts

user.update_attributes(name: 'Alice')
# => PUT http://api.com/users/3 - { user: { name: 'Alice' } }

user.destroy
# => DELETE http://api.com/users/3

User.create(name: 'Bob')
# => POST http://api.com/users - { user: { name: 'Bob' } }

Custom URIs

You can specify custom URIs on both the class and association level:

class User < Spyke::Base
  uri '/v1/users/(:id)' # id optional, both /v1/users and /v1/users/4 are valid

  has_many :posts, uri: '/posts/for_user/:user_id' # user_id is required
  has_one :image, uri: nil # only use embedded JSON
end

class Post < Spyke::Base
end

user = User.find(3) # => GET http://api.com/v1/users/3
user.image # Will only use embedded JSON and never call out to api
user.posts # => GET http://api.com/posts/for_user/3
Post.find(4) # => GET http://api.com/posts/4

Log output

When used with Rails, Spyke will automatically output helpful ActiveRecord-like messages to the main log:

Started GET "/posts" for 127.0.0.1 at 2014-12-01 14:31:20 +0000
Processing by PostsController#index as HTML
  Parameters: {}
  Spyke (40.3ms)  GET http://api.com/posts [200]
Completed 200 OK in 75ms (Views: 64.6ms | Spyke: 40.3ms | ActiveRecord: 0ms)

Contributing

If possible please take a look at the tests marked "wishlisted"! These are features/fixes we want to implement but haven't gotten around to doing yet :)