uuid

README

UUID package for Go language

Differences from satori/go.uuid

• Implementation of driver.Valuer returns nil instead for Nil UUID, to produce NULL in database fields. (Will panic if not nullable)
• Unmarshals NULL database value into Nil UUID.
• Provides Must helper instead of *OrNil functions.
• Provides methods to output base64 strings.
• Removes other parts of API that I don't need.

---

This package provides pure Go implementation of Universally Unique Identifier (UUID). Supported both creation and parsing of UUIDs.

With 100% test coverage and benchmarks out of box.

Supported versions:

• Version 1, based on timestamp and MAC address (RFC 4122)
• Version 2, based on timestamp, MAC address and POSIX UID/GID (DCE 1.1)
• Version 3, based on MD5 hashing (RFC 4122)
• Version 4, based on random numbers (RFC 4122)
• Version 5, based on SHA-1 hashing (RFC 4122)

Installation

Use the go command:

$ go get github.com/lwalen/uuid

Requirements

UUID package requires Go >= 1.2.

Example

package main

import (
	"fmt"
	"github.com/lwalen/uuid"
)

func main() {
	// Creating UUID Version 4
	u1 := uuid.NewV4()
	fmt.Printf("UUIDv4: %s\n", u1)

	// Parsing UUID from string input
	u2, err := uuid.FromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
	if err != nil {
		fmt.Printf("Something gone wrong: %s", err)
	}
	fmt.Printf("Successfully parsed: %s", u2)
}

Documentation

Documentation is hosted at GoDoc project.

Links

• RFC 4122
• DCE 1.1: Authentication and Security Services

Copyright

Copyright (C) 2013-2016 by Maxim Bublis b@codemonkey.ru.

UUID package released under MIT License. See LICENSE for details.

Documentation

Overview

Package uuid provides implementation of Universally Unique Identifier (UUID). Supported versions are 1, 3, 4 and 5 (as specified in RFC 4122) and version 2 (as specified in DCE 1.1).

Index

• Constants
• Variables
• func Equal(u1 UUID, u2 UUID) bool
• type UUID
  • func And(u1 UUID, u2 UUID) UUID
  • func FromBytes(input []byte) (u UUID, err error)
  • func FromString(input string) (u UUID, err error)
  • func Must(u UUID, err error) UUID
  • func NewV1() UUID
  • func NewV2(domain byte) UUID
  • func NewV3(ns UUID, name string) UUID
  • func NewV4() UUID
  • func NewV5(ns UUID, name string) UUID
  • func Or(u1 UUID, u2 UUID) UUID
  • func (u UUID) Base64() string
  • func (u UUID) Base64URL() string
  • func (u UUID) Bytes() []byte
  • func (u UUID) IsNil() bool
  • func (u UUID) MarshalBinary() (data []byte, err error)
  • func (u UUID) MarshalText() (text []byte, err error)
  • func (u *UUID) Scan(src interface{}) error
  • func (u *UUID) SetVariant()
  • func (u *UUID) SetVersion(v byte)
  • func (u UUID) String() string
  • func (u *UUID) UnmarshalBinary(data []byte) (err error)
  • func (u *UUID) UnmarshalText(text []byte) (err error)
  • func (u UUID) Value() (driver.Value, error)
  • func (u UUID) Variant() uint
  • func (u UUID) Version() uint

Constants

const (
	VariantNCS = iota
	VariantRFC4122
	VariantMicrosoft
	VariantFuture
)

UUID layout variants.

const (
	DomainPerson = iota
	DomainGroup
	DomainOrg
)

UUID DCE domains.

Variables

var (
	NamespaceDNS, _  = FromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
	NamespaceURL, _  = FromString("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
	NamespaceOID, _  = FromString("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
	NamespaceX500, _ = FromString("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
)

Predefined namespace UUIDs.

var Nil = UUID{}

Nil is a special form of UUID that is specified to have all 128 bits set to zero.

Functions

func Equal

func Equal(u1 UUID, u2 UUID) bool

Equal returns true if u1 and u2 equals, otherwise returns false.

Types

type UUID

type UUID [16]byte

UUID representation compliant with specification described in RFC 4122.

func And

func And(u1 UUID, u2 UUID) UUID

And returns result of binary AND of two UUIDs.

func FromBytes

func FromBytes(input []byte) (u UUID, err error)

FromBytes returns UUID converted from raw byte slice input. It will return error if the slice isn't 16 bytes long.

func FromString

func FromString(input string) (u UUID, err error)

FromString returns UUID parsed from string input. Input is expected in a form accepted by UnmarshalText.

func Must

func Must(u UUID, err error) UUID

Must is a helper that wraps a call to a function returning (UUID, error) and panics if the error is non-nil. It is intended for use in variable initializations such as

var u = uuid.Must(uuid.FromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8"))

func NewV1

func NewV1() UUID

NewV1 returns UUID based on current timestamp and MAC address.

func NewV2

func NewV2(domain byte) UUID

NewV2 returns DCE Security UUID based on POSIX UID/GID.

func NewV3

func NewV3(ns UUID, name string) UUID

NewV3 returns UUID based on MD5 hash of namespace UUID and name.

func NewV4

func NewV4() UUID

NewV4 returns random generated UUID.

func NewV5

func NewV5(ns UUID, name string) UUID

NewV5 returns UUID based on SHA-1 hash of namespace UUID and name.

func Or

func Or(u1 UUID, u2 UUID) UUID

Or returns result of binary OR of two UUIDs.

func (UUID) Base64

func (u UUID) Base64() string

Base64 returns the UUID as a base64 encoded string, without padding.

func (UUID) Base64URL

func (u UUID) Base64URL() string

Base64URL returns the UUID as a URL-safe base64 encoded string, without padding. '-' and '_' are used in place of '+' and '/', respectively.

func (UUID) Bytes

func (u UUID) Bytes() []byte

Bytes returns bytes slice representation of UUID.

func (UUID) IsNil

func (u UUID) IsNil() bool

IsNil reports whether the current UUID equals Nil.

func (UUID) MarshalBinary

func (u UUID) MarshalBinary() (data []byte, err error)

MarshalBinary implements the encoding.BinaryMarshaler interface.

func (UUID) MarshalText

func (u UUID) MarshalText() (text []byte, err error)

MarshalText implements the encoding.TextMarshaler interface. The encoding is the same as returned by String.

func (*UUID) Scan

func (u *UUID) Scan(src interface{}) error

Scan implements the sql.Scanner interface. A 16-byte slice is handled by UnmarshalBinary, while a longer byte slice or a string is handled by UnmarshalText.

func (*UUID) SetVariant

func (u *UUID) SetVariant()

SetVariant sets variant bits as described in RFC 4122.

func (*UUID) SetVersion

func (u *UUID) SetVersion(v byte)

SetVersion sets version bits.

func (UUID) String

func (u UUID) String() string

Returns canonical string representation of UUID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.

func (*UUID) UnmarshalBinary

func (u *UUID) UnmarshalBinary(data []byte) (err error)

UnmarshalBinary implements the encoding.BinaryUnmarshaler interface. It will return error if the slice isn't 16 bytes long.

func (*UUID) UnmarshalText

func (u *UUID) UnmarshalText(text []byte) (err error)

UnmarshalText implements the encoding.TextUnmarshaler interface. Following formats are supported: "6ba7b810-9dad-11d1-80b4-00c04fd430c8", "{6ba7b810-9dad-11d1-80b4-00c04fd430c8}", "urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"

func (UUID) Value

func (u UUID) Value() (driver.Value, error)

Value implements the driver.Valuer interface.

func (UUID) Variant

func (u UUID) Variant() uint

Variant returns UUID layout variant.

func (UUID) Version

func (u UUID) Version() uint

Version returns algorithm version used to generate UUID.