Youyouaidi is a Ruby Gem that offers a UUID class for generating, parsing, validating and converting UUIDs into / from shorter representations.
While a UUID consists of 36 characters – 32 hexadecimal characters, divided by four dashes into five subgroups – the short representation (invoked via
#to_short_string) consists of exactly 22 digit and lower- and uppercase characters.
This is what a valid, random (version 4) UUID looks like:
version either 8, 9 number a, or b ▼ ▼ caed3f49-b0ca-454b-adf8-5ee2a1764759 # chars in group: 8 | 4 | 4 | 4 | 12
As shown, the first digit of the third group indicates the UUID version.
The first digit of the fourth group always has to be one of either
All other digits are randomly assigned hexadecimals.
And this is the same UUID in its short format:
For UUID generation, the
SecureRandom.uuid method is used which generates valid, random version 4 UUIDs.
Find out more about UUIDs and the different versions on Wikipedia.
Add this line to your application's Gemfile:
And then execute:
Or install it yourself as:
$ gem install youyouaidi
UUID(...) is patched into the kernel as a shorthand call to
UUID is patched as a reference for the class
uuid_string = '550e8400-e29b-41d4-a716-446655440000' # A valid UUID in string format, has exactly 32 hexadecimal characters in 5 groups uuid_short = '2AuYQJcZeiIeCymkJ7tzTW' # Same UUID in its short format, has exactly 22 characters of [0-9a-zA-Z] uuid = UUID uuid_string # creates new Youyouaidi::UUID object, patches Youyouaidi::UUID.parse uuid_string into kernel. # => #<Youyouaidi::UUID:0x000001021f2590 @converter=Youyouaidi::Converter, @uuid="550e8400-e29b-41d4-a716-446655440000"> # Alternatively a short UUID can be passed: uuid = UUID uuid_short # creates similar Youyouaidi::UUID object # => #<Youyouaidi::UUID:0x00000102201b80 @converter=Youyouaidi::Converter, @uuid="550e8400-e29b-41d4-a716-446655440000"> # To generate a new random UUID simply do not pass a parameter: new_uuid = UUID() # generates a random UUID version 4 using the SecureRandom.uuid method # => #<Youyouaidi::UUID:0x00000102201b80 @converter=Youyouaidi::Converter, @uuid="27f8bc29-be8e-4dc7-ab30-0295b2a5e902">
Validity check and conversions
The validity check
UUID.valid? uuid_string checks, if UUID contains exactly 32 hexadecimal characters which are divided by four dashes ('-') into five groups of sizes 8, 4, 4, 4, and 12.
Also, it validates that the first character of the fourth group is either a
a, or a
uuid_string = '550e8400-e29b-41d4-a716-446655440000' # A valid UUID in string format uuid = UUID uuid_string UUID.valid? uuid_string # Checks if `uuid_string' is a valid UUID, same as Youyouaidi::UUID.valid? uuid_string # => true uuid.to_s # Returns the string representation of the UUID object # => '550e8400-e29b-41d4-a716-446655440000' uuid.to_short_string # Returns the short string representation of the UUID object, #to_param is an alias for this method # => '2AuYQJcZeiIeCymkJ7tzTW'
uuid_string = '550e8400-e29b-41d4-a716-446655440000' # A valid UUID in string format uuid = UUID uuid_string similar_uuid = UUID uuid_string other_uuid = UUID '00000000-1111-2222-aaaa-eeeeeeeeeeee' uuid == similar_uuid # Two UUID objects representing same UUID (#=== behaves similar for this) # => true uuid == other_uuid # Two UUID objects representing different UUIDs (#=== behaves similar for this) # => false uuid == uuid_string # Comparing a UUID object and its string representation with `==' # => false uuid === uuid_string # Comparing a UUID object and its string representation with `===' (case insensetive) # => true
- Fork it ( http://github.com/nicolas-fricke/youyouaidi/fork )
- Create your feature branch (
git checkout -b my-new-feature)
- Commit your changes (
git commit -am 'Add some feature')
- Push to the branch (
git push origin my-new-feature)
- Create new Pull Request