isabella232 / instructure_registrar

InstructureRegistrar

InstructureRegistrar is a Ruby library for registering and retrieving service information from a central etcd service registry.

Installation

Add this line to your application's Gemfile:

gem 'instructure_registrar'

And then execute:

$ bundle

Usage

Make sure that the following environment variables are set with the appropriate information for your local etcd instance:

REGISTRY_HOST
REGISTRY_PORT

Integrating with a service

In your service's project folder, create a configuration file with the following contents:

#/config/initializers/instructure_registrar.rb
require 'instructure_registrar'
require 'dotenv'
Dotenv.load

InstructureRegistrar.configure do |config|
  config.registry_host = ENV['REGISTRY_HOST']# || "http://instructure-etcd.docker"
  config.registry_port = ENV['REGISTRY_PORT']# || 12379
  config.service_name  = "sample_service_3"
  config.service_config = {
    host: "http://someservice.docker",
    token: 'foo',
    option: 'bar'}
end

if ENV['RAILS_ENV'] == "development"
  InstructureRegistrar.register
  at_exit { InstructureRegistrar.unregister }
end

Looking up a service

Note that your client application will need a config file similar to that in the section above, but unless you plan on registering your app as a service your config file will be simpler:

#/config/initializers/instructure_registrar.rb
require 'dotenv'
Dotenv.load
require 'instructure_registrar'

InstructureRegistrar.configure do |config|
  config.registry_host = ENV.fetch('REGISTRY_HOST') || "http://instructure-etcd.docker"
  config.registry_port = ENV.fetch("REGISTRY_PORT") || 12379
end

Then, to fetch connection information for a given service:

require 'instructure_registrar'
@some_service_url = InstructureRegistrar.get_service('some_service_name')

This will return all keys and values associated with the service.