require 'rack'
require './dnsbl_exporter'


run lambda {|env|
  begin
    req = Rack::Request.new env
    case req.path
    when '/metrics'
      collector = DnsblCollector.new
      target =
        begin
          target = IPAddr.new req.params['target']
        rescue IPAddr::AddressFamilyError
          return [400, {"Content-Type" => "text/plain"}, ["Valid target-IP-Address expected.\n"]]
        end
      collector.collect target
      [200, {"Content-Type" => "text/plain"}, [
        Prometheus::Client::Formats::Text.marshal( collector.prometheus)
      ]]
    else
      [404, {"Content-Type" => "text/plain"}, ["Not found.\nYou want to try /metrics?\n"]]
    end
  rescue
    STDERR.puts "#$! (#{$!.class})", $!.backtrace
    [500, {"Content-Type" => "text/plain"}, ["Server-error.\n"]]
  end
}