ServiceContract

The gem tries to abstract the definition of a service's interface contract

Installation

Add this line to your application's Gemfile:

gem 'service_contract'

And then execute:

$ bundle

Or install it yourself as:

$ gem install service_contract

Providers

Avro

We can read an Avro protocol file to determine a set of service definitions.

Example:

class Gnomon::Contract::Service < ServiceContract::Avro::Service
  def self.data_dir
    return "/path/to/avro_files"
  end
end

Usage

We define a service as having many versions with each version having several Protocols. A Protocol has many Endpoints.

Example:

# a Gnomon::Contract::Service instance (subclass of ServiceContract::AbstractService)
version = Gnomon::Contract::Service.find(1)
=> <#Gnomon::Contract::Service>

protocol = version.protocol("location")
=> <#ServiceContract::Avro::Protocol>

protocol.endpoints
=> [<#ServiceContract::Avro::Endpoint>,...]

Documentation

service_contract also provides a nice documentation layer packaged in the form of a sinatra rack application.

module Gnomon
  module Contract
    class Documentation < ServiceContract::Avro::Documentation
      helpers do
        def service
          Gnomon::Contract::Service
        end
      end
    end
  end
end

# in your rackup config
run Gnomon::Contract::Documentation

# or mount in rails routes
MyApplication.routes.draw do
  mount Gnomon::Contract::Documentation, at: "docs/"
end

Note: You will have to add sinatra and slim (templating engine) to your gem dependencies yourself because it's not a core dependency.