simple sinatra-synchrony/postgres example

app.rb

require 'json'

class App < Sinatra::Base
  register Sinatra::Synchrony

  use Rack::JSONP
  before { content_type 'application/json' }

  get '/' do
    "hello async".to_json
  end

  get '/delay/:n' do |n|
    EM::Synchrony.sleep n.to_i
    "delayed for #{n} seconds".to_json
  end
  
  get '/db/:n' do |n|
    DB.query("SELECT NOW(), pg_sleep(#{n.to_i})") do |result|
      result.first.to_json
    end
  end
end

config.ru

Bundler.require
require './app'

DB = EM::Synchrony::ConnectionPool.new(size: 10) do  
  uri = URI.parse(ENV['DATABASE_URL'])
  PG::EM::Client.new(host: uri.host, port: uri.port, user: uri.user, password: uri.password, dbname: uri.path[1..-1])
end

run App

Gemfile

source :rubygems

gem 'thin'
gem 'sinatra-synchrony'
gem 'em-pg-client', require: %w'pg/em em-synchrony/pg'
gem 'rack-contrib'
gem 'rspec'
gem 'rack-test'

Gemfile.lock

GEM
  remote: http://rubygems.org/
  specs:
    addressable (2.3.2)
    cookiejar (0.3.0)
    daemons (1.1.9)
    diff-lcs (1.1.3)
    em-http-request (1.0.3)
      addressable (>= 2.2.3)
      cookiejar
      em-socksify
      eventmachine (>= 1.0.0.beta.4)
      http_parser.rb (>= 0.5.3)
    em-pg-client (0.2.1)
      eventmachine (>= 0.12.10)
      pg (>= 0.13.2)
    em-resolv-replace (1.1.3)
    em-socksify (0.2.1)
      eventmachine (>= 1.0.0.beta.4)
    em-synchrony (1.0.2)
      eventmachine (>= 1.0.0.beta.1)
    eventmachine (1.0.0)
    http_parser.rb (0.5.3)
    pg (0.14.1)
    rack (1.4.1)
    rack-contrib (1.1.0)
      rack (>= 0.9.1)
    rack-fiber_pool (0.9.2)
    rack-protection (1.2.0)
      rack
    rack-test (0.6.2)
      rack (>= 1.0)
    rspec (2.11.0)
      rspec-core (~> 2.11.0)
      rspec-expectations (~> 2.11.0)
      rspec-mocks (~> 2.11.0)
    rspec-core (2.11.1)
    rspec-expectations (2.11.3)
      diff-lcs (~> 1.1.3)
    rspec-mocks (2.11.3)
    sinatra (1.3.3)
      rack (~> 1.3, >= 1.3.6)
      rack-protection (~> 1.2)
      tilt (~> 1.3, >= 1.3.3)
    sinatra-synchrony (0.4.1)
      em-http-request (~> 1.0)
      em-resolv-replace (~> 1.1)
      em-synchrony (~> 1.0.1)
      eventmachine (~> 1.0.0)
      rack-fiber_pool (~> 0.9)
      sinatra (~> 1.0)
    thin (1.5.0)
      daemons (>= 1.0.9)
      eventmachine (>= 0.12.6)
      rack (>= 1.0.0)
    tilt (1.3.3)

PLATFORMS
  ruby

DEPENDENCIES
  em-pg-client
  rack-contrib
  rack-test
  rspec
  sinatra-synchrony
  thin

spec.rb

Bundler.require
require './app'

App.set :environment, :test

Sinatra::Synchrony.patch_tests!

describe App do
  include Rack::Test::Methods
  
  def app
    App
  end
  
  it 'says hello' do
    get '/'
    last_response.ok?.should be_true
    last_response.body.should == '"hello async"'
  end
  
  it 'says hello' do
    get '/delay/1'
    last_response.ok?.should be_true
    last_response.body.should == '"delayed for 1 seconds"'
  end
end