pushme.rb

require 'httparty'
require 'json'
require 'openssl'

HUB_URL    = "http://localhost:4000/push"
STORE_ID   = "5180e2507575e48dd0000001"
STORE_SECRET_KEY = "1234567890"

timestamp  = Time.now.utc().to_i - 4600

json_payload = JSON.generate({
  orders: [ { id: 'R1234', status: 'cancelled' } ]
})

data = "#{json_payload}#{timestamp}"

SHA1 = OpenSSL::Digest::Digest.new('sha1')
access_token = OpenSSL::HMAC.hexdigest(SHA1, STORE_SECRET_KEY, data)

response = HTTParty.post(HUB_URL, {
  body: json_payload,
  headers: {
   'X-Hub-Store'        => STORE_ID,
   'X-Hub-Access-Token1' => access_token,
   'X-Hub-Timestamp'    => timestamp.to_s
  }
})

puts response.code # 202
puts response.body # {"orders":1}