persistent connections example

persistent_connections.rb

# This example fetches accounts of my 10 followers using Github's API
# One version uses Connection: keep-alive, the other one uses Connection: close

require 'net/https'
require 'uri'
require 'json'
require 'benchmark'

def request(uri, persistent = true)
  req = Net::HTTP::Get.new uri
  req.add_field 'Connection', persistent ? 'keep-alive' : 'close'
  req
end

def fetch(persistent = true)
  uri = URI.parse("https://api.github.com")

  http = Net::HTTP.new(uri.host, uri.port)
  http.use_ssl = true
  # Just for demo, don't do this at home ;)
  http.verify_mode = OpenSSL::SSL::VERIFY_NONE
  http.start

  response = http.request( request( "/users/drogus/followers", persistent ) )
  followers = JSON.parse(response.body)

  followers[0..10].each do |follower|
    http.request( request( follower["url"], persistent ) )
  end
end

Benchmark.bm(14) do |x|
  x.report("persistent    ") { fetch(true) }
  x.report("non-persistent") { fetch(false) }
end

results.txt

                    user     system      total        real
persistent      0.010000   0.000000   0.010000 (  2.775020)
non-persistent  0.040000   0.020000   0.060000 (  8.170520)