How to generate promotional codes?

Question

Programming

Good afternoon!
Tell me, plz, how to generate promotional codes? Perhaps there is an established algorithm/service.
Requirements "standard":

• Uniqueness (quantity is not limited)
  
• Difficult to pick up
  
• Going out of order/not having an easily identifiable system
  
• Average length of a promotional message (it is planned to be placed on physical media, cards, packages, etc.)
  
• A set of Latin letters and numbers, human-readable is not required
  
• Automated Generation
  

Thank you!
ps it is clear that it is easy to program yourself; interested in best-practices)

Answer 1

1. Generate a completely random string with the desired length/character parameters
2. check if it exists in the database
3. if so, then n 1.
4. save it to the database.
You are welcome!

Answer 2

A GUID is perfect for you.

Answer 3

pwgen will handle it

Answer 4

• choose an algorithm/hash with a uniform distribution.
  
• choose a range such that the probability of a code match in relation to the number of promo codes issued is small. If you have a federal network, then the promotional code will be longer, if a small store, then shorter. Perhaps you want the promotional code not to be repeated, then the probability of a collision needs to be further reduced, the promotional code will be more authentic.
  
• choose a custom random number generator. Use non-standard seed/salt/set up for a while/set up for equipment.
  

Answer 5

Usually a promotional code consists of 3-4 blocks of 4-5 characters.
You can add to the prefix or postfix (at the beginning, at the end), for example, a year.
Perhaps this service will suit you:
https://pswrd.getcode.xyz/