The uuid package generates and inspects UUIDs.
UUIDs are based on RFC 4122 and DCE 1.1: Authentication and Security Services.
- func ClockSequence() int
- func Equal(uuid1, uuid2 UUID) bool
- func New() string
- func NodeID() byte
- func NodeInterface() string
- func SetClockSequence(seq int)
- func SetNodeID(id byte) bool
- func SetNodeInterface(name string) bool
- func SetRand(r io.Reader)
- type Domain
- type Time
- type UUID
- func NewDCEGroup() UUID
- func NewDCEPerson() UUID
- func NewDCESecurity(domain Domain, id uint32) UUID
- func NewHash(h hash.Hash, space UUID, data byte, version int) UUID
- func NewMD5(space UUID, data byte) UUID
- func NewRandom() UUID
- func NewSHA1(space UUID, data byte) UUID
- func NewUUID() UUID
- func Parse(s string) UUID
- func (uuid UUID) ClockSequence() (int, bool)
- func (uuid UUID) Domain() (Domain, bool)
- func (uuid UUID) Id() (uint32, bool)
- func (uuid UUID) NodeID() byte
- func (uuid UUID) String() string
- func (uuid UUID) Time() (Time, bool)
- func (uuid UUID) URN() string
- func (uuid UUID) Variant() Variant
- func (uuid UUID) Version() (Version, bool)
- type Variant
- type Version
Domain constants for DCE Security (Version 2) UUIDs.
Constants returned by Variant.
var ( NameSpace_DNS = Parse("6ba7b810-9dad-11d1-80b4-00c04fd430c8") NameSpace_URL = Parse("6ba7b811-9dad-11d1-80b4-00c04fd430c8") NameSpace_OID = Parse("6ba7b812-9dad-11d1-80b4-00c04fd430c8") NameSpace_X500 = Parse("6ba7b814-9dad-11d1-80b4-00c04fd430c8") NIL = Parse("00000000-0000-0000-0000-000000000000") )
Well known Name Space IDs and UUIDs
func ClockSequence ¶
func ClockSequence() int
ClockSequence returns the current clock sequence, generating one if not already set. The clock sequence is only used for Version 1 UUIDs.
The uuid package does not use global static storage for the clock sequence or the last time a UUID was generated. Unless SetClockSequence a new random clock sequence is generated the first time a clock sequence is requested by ClockSequence, GetTime, or NewUUID. (section 22.214.171.124) sequence is generated for
func New() string
New returns a new random (version 4) UUID as a string. It is a convenience function for NewRandom().String().
func NodeID() byte
NodeID returns a slice of a copy of the current Node ID, setting the Node ID if not already set.
func NodeInterface ¶
func NodeInterface() string
NodeInterface returns the name of the interface from which the NodeID was derived. The interface "user" is returned if the NodeID was set by SetNodeID.
func SetClockSequence ¶
func SetClockSequence(seq int)
SetClockSeq sets the clock sequence to the lower 14 bits of seq. Setting to -1 causes a new sequence to be generated.
SetNodeID sets the Node ID to be used for Version 1 UUIDs. The first 6 bytes of id are used. If id is less than 6 bytes then false is returned and the Node ID is not set.
func SetNodeInterface ¶
SetNodeInterface selects the hardware address to be used for Version 1 UUIDs. If name is "" then the first usable interface found will be used or a random Node ID will be generated. If a named interface cannot be found then false is returned.
SetNodeInterface never fails when name is "".
type Domain byte
A Domain represents a Version 2 domain
type Time int64
A Time represents a time as the number of 100's of nanoseconds since 15 Oct 1582.
GetTime returns the current Time (100s of nanoseconds since 15 Oct 1582) and adjusts the clock sequence as needed. An error is returned if the current time cannot be determined.
type UUID byte
A UUID is a 128 bit (16 byte) Universal Unique IDentifier as defined in RFC 4122.
func NewDCEGroup ¶
func NewDCEGroup() UUID
NewDCEGroup returns a DCE Security (Version 2) UUID in the group domain with the id returned by os.Getgid.
func NewDCEPerson ¶
func NewDCEPerson() UUID
NewDCEPerson returns a DCE Security (Version 2) UUID in the person domain with the id returned by os.Getuid.
func NewDCESecurity ¶
NewDCESecurity returns a DCE Security (Version 2) UUID.
The domain should be one of Person, Group or Org. On a POSIX system the id should be the users UID for the Person domain and the users GID for the Group. The meaning of id for the domain Org or on non-POSIX systems is site defined.
For a given domain/id pair the same token may be returned for up to 7 minutes and 10 seconds.
NewHash returns a new UUID dervied from the hash of space concatenated with data generated by h. The hash should be at least 16 byte in length. The first 16 bytes of the hash are used to form the UUID. The version of the UUID will be the lower 4 bits of version. NewHash is used to implement NewMD5 and NewSHA1.
NewMD5 returns a new MD5 (Version 3) UUID based on the supplied name space and data.
NewHash(md5.New(), space, data, 3)
func NewRandom() UUID
Random returns a Random (Version 4) UUID or panics.
The strength of the UUIDs is based on the strength of the crypto/rand package.
A note about uniqueness derived from from the UUID Wikipedia entry:
Randomly generated UUIDs have 122 random bits. One's annual risk of being hit by a meteorite is estimated to be one chance in 17 billion, that means the probability is about 0.00000000006 (6 × 10−11), equivalent to the odds of creating a few tens of trillions of UUIDs in a year and having one duplicate.
NewSHA1 returns a new SHA1 (Version 5) UUID based on the supplied name space and data.
NewHash(sha1.New(), space, data, 5)
func NewUUID() UUID
NewUUID returns a Version 1 UUID based on the current NodeID and clock sequence, and the current time. If the NodeID has not been set by SetNodeID or SetNodeInterface then it will be set automatically. If the NodeID cannot be set NewUUID returns nil. If clock sequence has not been set by SetClockSequence then it will be set automatically. If GetTime fails to return the current NewUUID returns nil.
Parse decodes s into a UUID or returns nil. Both the UUID form of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx and urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx are decoded.
func (UUID) ClockSequence ¶
ClockSequence returns the clock sequence encoded in uuid. It returns false if uuid is not valid. The clock sequence is only well defined for version 1 and 2 UUIDs.
Domain returns the domain for a Version 2 UUID or false.
Id returns the id for a Version 2 UUID or false.
NodeID returns the 6 byte node id encoded in uuid. It returns nil if uuid is not valid. The NodeID is only well defined for version 1 and 2 UUIDs.
String returns the string form of uuid, xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx , or "" if uuid is invalid.
Time returns the time in 100s of nanoseconds since 15 Oct 1582 encoded in uuid. It returns false if uuid is not valid. The time is only well defined for version 1 and 2 UUIDs.
URN returns the RFC 2141 URN form of uuid, urn:uuid:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx, or "" if uuid is invalid.
Variant returns the variant encoded in uuid. It returns Invalid if uuid is invalid.
type Variant byte
A Variant represents a UUIDs variant.