Is there a way to generate a unique integer permalink?

Question

I am trying to create a unique numeric permalink in rails. My problem is that I need to make sure it is unique, has between 5 and 7 numbers and is randomly generated (so not simply counting up). I did look at FriendlyID but I am not sure if this can deliver what I need - the url for my permalink should eventually look like this:

www.kreelu.com/4325677

Is there a build in feature or a gem that can provide this?

Thanks!

Do you require any security on this? 5 digits is not really enough to be secure if you have even a moderate number (e.g. 10) of valid numbers. Could you clarify the purpose? — Neil Slater, Apr 04 '14 at 11:02
I think you can use has_permalink gem. i am not sure your purpose solved but it is helpfull to you. See the url http://haspermalink.org/ — Abid Hussain, Apr 04 '14 at 11:05
You save the permalinks right? Just use ruby's rand() method with a range excluding the existig permalinks from range — SG 86, Apr 04 '14 at 11:09
http://stackoverflow.com/questions/119107/how-do-i-generate-a-list-of-n-unique-random-numbers-in-ruby — SG 86, Apr 04 '14 at 11:14
@neilSlater It doesn't need to be secure since it will only be accessible from time to time (it basically exposes a page temporarily under specific circumstances and takes it offline once the conditions change) — Thomas Kuhlmann, Apr 10 '14 at 18:31

score 1 · Accepted Answer · answered Apr 04 '14 at 11:13

after_validation :set_permalink

def rand_permalink #you can find a better way to exclude loop db-searches
  r = rand.to_s[2..8] # 7-digit random, you can make [2..11] for 10-digits and so on
  while find_by_permalink(r).present?
    r = rand.to_s[2..8]
  end
  r      
end 


def set_permalink
  permalink = rand_permalink unless permalink.presence
end

score 1 · Answer 2 · answered Apr 04 '14 at 11:20

Assuming you want to create the unique permalink on create, you want to store it in your database and the class is named Post:

validate :permalink, :uniqueness => true

before_create :create_permalink

private
  def create_permalink
    loop do
      self.permalink = Array(1..7).map{ rand(10).to_s }.join
      return if Posts.where(permalink: permalink).blank?
    end
  end

Is there a way to generate a unique integer permalink?

2 Answers2