system_timeout2.rb

require 'system_timer'
require 'uri'

bad_url = 'postgres://some:user@1.2.3.4/mydb'
good_url = 'postgres://postgres@localhost/template1'

uri = URI.parse(good_url)

success = nil

SystemTimer.timeout(1) do
	begin
		result = `PGPASSWORD=#{uri.password} psql -h #{uri.host} -U #{uri.user} #{uri.path.gsub(/^\//, '')} -c 'select 1' 2>& 1`
		success = result.match(/\(1 row\)/)
	rescue Timeout::Error
		success = false
	end
end

puts "server is #{success ? 'up' : 'down'}"