gistfile1.rb

require 'net/http'

#send get request to Heroku app
http = Net::HTTP.new("http://xxxxx.herokuapp.com/")

request = Net::HTTP::Get.new("/available.json")
response = http.request(request)

# error
# getaddrinfo: nodename nor servname provided, or not known (SocketError)

# curl works fine
# curl http://xxxxx.herokuapp.com/available.json
# {"available":["user1","user2"]}