Who's On Call In Service Now

who_is_on_call.rb

#!/usr/bin/env ruby

require 'rest_client'

@username = URI.encode_www_form_component('username')
@password = URI.encode_www_form_component('password')
@host = 'yoursite.service-now.com'

def uri(table = @table)
  return URI::HTTPS.build( {
    :userinfo => "#{@username}:#{@password}",
    :host     => @host,
    :path     => "/#{table}.do",
    :query    => 'JSONv2'
  } )
end

def api_call(params, table = @table)
  callback = RestClient.post(
    uri(table).to_s,
    params.to_json,
    :content_type => :json,
    :accept       => :json
  )

  callback = JSON.parse(callback)

  # http://wiki.servicenow.com/index.php?title=JSONv2_Web_Service#JSON_Success_Response
  if callback['error']
    raise "#{callback['error']}"
  else
    return callback
  end
end

def get_records(table = @table)
  params = {:sysparm_action=>"getRecords", :sysparm_query=>"active=true", :displayvalue => true, :displayvariables => true}
  api_call(params, table)
end

def get_keys(table = @table)
  params = {:sysparm_action=>"getKeys", :sysparm_query=>"active=true"}
  api_call(params, table)
end

def get_sys_id(sys_id, table = @table)
  params = {:sysparm_action=>"get", :sysparm_sys_id => sys_id}
  api_call(params, table)
end

def human_name(sys_id)
  get_sys_id(sys_id, "sys_user")['records'][0]["name"]
end

#### MAIN ####

# get the rotation roster
roster = get_records('cmn_rota_roster')['records'].first
members = get_records('cmn_rota_member')['records']

# get the start date of the rotation
d = roster['rotation_start_date']
t = roster['rotation_start_time']
start_date = Time.strptime(d + t, "%Y%m%d%H%M%S")

# get the rotation with human names and order
human_order = Hash[ members.map { |x| [ x['order'], human_name(x['member']) ] } ]
## => {"200"=>"John Doe", "100"=>"Bob Doe", "300"=>"Jane Doe"}
# sort it to return an array of names
names = human_order.sort_by { |order, name| order }.map { |x| x[1] }
## => ["Bob Doe", "John Doe", "Jane Doe"]

cycle = names.cycle

# for each week passed from the starting date till today, cycle through the names

weeks_passed = ((Time.now - start_date) / 86400 / 7).to_i

weeks_passed.times do
  cycle.next
end

current_on_call = cycle.next

puts current_on_call

#### END MAIN ####