Jupiter System For gas tanks monitor

Code:
url = 'http://192.168.1.1/WacMobileService/WebService1.asmx/GetWacStatuses?UserName=string&Password=string&GroupId=string&SubGroupId=string&bOnlyWithAlerts=string&RequiredAlertsBitmap=string&MaxResults=string'
data, err = require('socket.http').request(url)

log('result', data, err)

if not data then
  return
end

sites = {}

callbacks = {
  StartElement = function(p, tag)
    ctag = tag

    if tag == 'wSiteStatus' then
      site = { status = {} }
      state = 'site'
    elseif tag == 'wBulkStatus' then
      status = {}
      state = 'status'
    end
  end,
  EndElement = function(p, tag)
    ctag = nil

    if tag == 'wSiteStatus' then
      state = nil

      if site.SiteId then
        sites[ site.SiteId ] = site
      end
    elseif tag == 'wBulkStatus' then
      state = 'site'

      if status.BulkId then
        site.status[ status.BulkId ] = status
      end
    end
  end,
  CharacterData = function(p, value)
    value = value:trim()

    if #value == 0 or not ctag then
      return
    end

    if state == 'site' then
      site[ ctag ] = value
    elseif state == 'status' then
      status[ ctag ] = value
    end
  end
}

parser = require('lxp').new(callbacks)
parser:parse(data)
parser:close()

log(sites)