Class that handles generation and validation of UUIDs. Whenever you want to associate an identifier with something, you should use this class rather than (e.g.) relying on identifiers generated by a database. This allows you to cluster your database later on, should your application become big enough, without having to worry about ID synchronisation across instances.

Methods
G
V
Constants
MATCH_16_PAIRS_OF_HEX_DIGITS = 
/^([[:xdigit:]]{2}){16}$/
 

A regexp which, as its name suggests, only matches a string that contains 16 pairs of hex digits (with upper or lower case A-F). Legacy value kept in case third party client code is using it.

stackoverflow.com/questions/287684/regular-expression-to-validate-hex-string
MATCH_V4_UUID = 
/^[a-fA-F0-9]{12}4[a-fA-F0-9]{3}[89aAbB][a-fA-F0-9]{15}$/
 

A regexp which matches V4 UUIDs with hyphens removed. Note that this is more strict than MATCH_16_PAIRS_OF_HEX_DIGITS.
Class Public methods
generate()

Generate a unique identifier. Returns a 32 character string.

Source: show 

# File lib/hoodoo/utilities/uuid.rb, line 29
def self.generate
  ::SecureRandom.uuid().gsub!( '-', '' )
end
valid?( uuid )

Checks if a UUID string is valid. Returns true if so, else false.

uuid

Quantity to validate.

The method will only return true if the input parameter is a String containing 32 mostly random hex digits representing a valid V4 UUID with hyphens removed.

Note that the validity of a UUID says nothing about where, if anywhere, it might have been used. So, just because a UUID is valid, doesn't mean you have (say) stored something with that UUID as the primary key in a row in a database.

Source: show 

# File lib/hoodoo/utilities/uuid.rb, line 46
def self.valid?( uuid )
  uuid.is_a?( ::String ) && ( uuid =~ MATCH_V4_UUID ) != nil
end