go-nanoid

Install the go-nanoid package using the go get tool. Ensure you use the /v2 suffix to pull the correct major version.

$ go get github.com/matoous/go-nanoid/v2

Use gonanoid.Generate(alphabet string, size int) to create an ID with a specific set of characters and a specific length.

id, err := gonanoid.Generate("abcde", 54)

Use gonanoid.New() to generate a cryptographically secure, compact ID using the default alphabet and length.

id, err := gonanoid.New()

Use New() to generate a secure, URL-friendly unique ID using the default alphabet (_-0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ).

You can optionally provide a single integer argument to specify the desired length of the ID. If no argument is provided, it defaults to a length of 21.

Errors:

• Returns an error if a negative length is provided.
• Returns an error if more than one argument is provided.
• Returns an error if the underlying random number generator fails.

Use Generate(alphabet string, size int) when you need to use a specific set of characters and a specific ID length. This is a low-level function that allows for full customization of the ID generation process.

Errors:

• Returns an error if the alphabet is empty or contains more than 255 characters.
• Returns an error if the size is not a positive integer.
• Returns an error if the underlying random number generator fails.

If you prefer to avoid manual error checking and are confident in your parameters, use the Must variants. These functions will panic if an error occurs during generation.

• Must(...int) is the panic-equivalent of New().
• MustGenerate(alphabet string, size int) is the panic-equivalent of Generate().

The package provides several predefined alphabets for common use cases: