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UuidV2

DCE Security version, or version 2, UUIDs include local domain identifier, local ID for the specified domain, and node values that are combined into a 128-bit unsigned integer

It is important to note that a version 2 UUID suffers from some loss of fidelity of the timestamp, due to replacing the time_low field with the local identifier. When constructing the timestamp value for date purposes, we replace the local identifier bits with zeros. As a result, the timestamp can be off by a range of 0 to 429.4967295 seconds (or 7 minutes, 9 seconds, and 496730 microseconds).

Astute observers might note this value directly corresponds to 2^32 - 1, or 0xffffffff. The local identifier is 32-bits, and we have set each of these bits to 0, so the maximum range of timestamp drift is 0x00000000 to 0xffffffff (counted in 100-nanosecond intervals).

See Also:

  • https://publications.opengroup.org/c311 - DCE 1.1: Authentication and Security Services
  • https://publications.opengroup.org/c706 - DCE 1.1: Remote Procedure Call
  • https://pubs.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01 - DCE 1.1: Auth & Sec, §5.2.1.1
  • https://pubs.opengroup.org/onlinepubs/9696989899/chap11.htm#tagcjh_14_05_01_01 - DCE 1.1: Auth & Sec, §11.5.1.1
  • https://pubs.opengroup.org/onlinepubs/9629399/apdxa.htm - DCE 1.1: RPC, Appendix A
  • https://github.com/google/uuid - Go package for UUIDs (includes DCE implementation)

Methods

__construct

Creates a version 2 (DCE Security) UUID

public __construct(\Ramsey\Uuid\Rfc4122\FieldsInterface $fields, \Ramsey\Uuid\Converter\NumberConverterInterface $numberConverter, \Ramsey\Uuid\Codec\CodecInterface $codec, \Ramsey\Uuid\Converter\TimeConverterInterface $timeConverter): mixed

Parameters:

Parameter Type Description
$fields \Ramsey\Uuid\Rfc4122\FieldsInterface The fields from which to construct a UUID
$numberConverter \Ramsey\Uuid\Converter\NumberConverterInterface The number converter to use
for converting hex values to/from integers
$codec \Ramsey\Uuid\Codec\CodecInterface The codec to use when encoding or decoding
UUID strings
$timeConverter \Ramsey\Uuid\Converter\TimeConverterInterface The time converter to use
for converting timestamps extracted from a UUID to unix timestamps

getLocalDomain

Returns the local domain used to create this version 2 UUID

public getLocalDomain(): int

getLocalDomainName

Returns the string name of the local domain

public getLocalDomainName(): string

getLocalIdentifier

Returns the local identifier for the domain used to create this version 2 UUID

public getLocalIdentifier(): \Ramsey\Uuid\Type\Integer

Inherited methods

getClockSeqHiAndReserved

public getClockSeqHiAndReserved(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getClockSeqHiAndReservedHex

public getClockSeqHiAndReservedHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getClockSeqLow

public getClockSeqLow(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getClockSeqLowHex

public getClockSeqLowHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getClockSequence

public getClockSequence(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getClockSequenceHex

public getClockSequenceHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getNumberConverter

public getNumberConverter(): \Ramsey\Uuid\Converter\NumberConverterInterface
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getDateTime

Returns a DateTimeInterface object representing the timestamp associated with the UUID

public getDateTime(): \DateTimeImmutable

Return Value:

A PHP DateTimeImmutable instance representing the timestamp of a time-based UUID

getFieldsHex

public getFieldsHex(): string[]
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getLeastSignificantBits

public getLeastSignificantBits(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getLeastSignificantBitsHex

public getLeastSignificantBitsHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getMostSignificantBits

public getMostSignificantBits(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getMostSignificantBitsHex

public getMostSignificantBitsHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getNode

public getNode(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getNodeHex

public getNodeHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeHiAndVersion

public getTimeHiAndVersion(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeHiAndVersionHex

public getTimeHiAndVersionHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeLow

public getTimeLow(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeLowHex

public getTimeLowHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeMid

public getTimeMid(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimeMidHex

public getTimeMidHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimestamp

public getTimestamp(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getTimestampHex

public getTimestampHex(): string
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getVariant

public getVariant(): ?int
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

getVersion

public getVersion(): ?int
  • Warning: this method is deprecated. This means that this method will likely be removed in a future version.

__construct

Creates a universally unique identifier (UUID) from an array of fields

public __construct(\Ramsey\Uuid\Rfc4122\FieldsInterface $fields, \Ramsey\Uuid\Converter\NumberConverterInterface $numberConverter, \Ramsey\Uuid\Codec\CodecInterface $codec, \Ramsey\Uuid\Converter\TimeConverterInterface $timeConverter): mixed

Unless you're making advanced use of this library to generate identifiers that deviate from RFC 4122, you probably do not want to instantiate a UUID directly. Use the static methods, instead:

use Ramsey\Uuid\Uuid;

$timeBasedUuid = Uuid::uuid1();
$namespaceMd5Uuid = Uuid::uuid3(Uuid::NAMESPACE_URL, 'http://php.net/');
$randomUuid = Uuid::uuid4();
$namespaceSha1Uuid = Uuid::uuid5(Uuid::NAMESPACE_URL, 'http://php.net/');

Parameters:

Parameter Type Description
$fields \Ramsey\Uuid\Rfc4122\FieldsInterface The fields from which to construct a UUID
$numberConverter \Ramsey\Uuid\Converter\NumberConverterInterface The number converter to use
for converting hex values to/from integers
$codec \Ramsey\Uuid\Codec\CodecInterface The codec to use when encoding or decoding
UUID strings
$timeConverter \Ramsey\Uuid\Converter\TimeConverterInterface The time converter to use
for converting timestamps extracted from a UUID to unix timestamps

__toString

Casts the UUID to the string standard representation

public __toString(): string

jsonSerialize

Converts the UUID to a string for JSON serialization

public jsonSerialize(): string

serialize

Converts the UUID to a string for PHP serialization

public serialize(): string

__serialize

public __serialize(): array{bytes: string}

unserialize

Re-constructs the object from its serialized form

public unserialize(string $data): void

Parameters:

Parameter Type Description
$data string The serialized PHP string to unserialize into
a UuidInterface instance

__unserialize

public __unserialize(array{bytes?: string} $data): void

Parameters:

Parameter Type Description
$data array{bytes?: string}

compareTo

Returns -1, 0, or 1 if the UUID is less than, equal to, or greater than the other UUID

public compareTo(\Ramsey\Uuid\UuidInterface $other): int<-1, 1>

The first of two UUIDs is greater than the second if the most significant field in which the UUIDs differ is greater for the first UUID.

  • Q. What's the value of being able to sort UUIDs?
  • A. Use them as keys in a B-Tree or similar mapping.

Parameters:

Parameter Type Description
$other \Ramsey\Uuid\UuidInterface The UUID to compare

Return Value:

-1, 0, or 1 if the UUID is less than, equal to, or greater than $other

equals

Returns true if the UUID is equal to the provided object

public equals(?object $other): bool

The result is true if and only if the argument is not null, is a UUID object, has the same variant, and contains the same value, bit for bit, as the UUID.

Parameters:

Parameter Type Description
$other ?object An object to test for equality with this UUID

Return Value:

True if the other object is equal to this UUID

getBytes

Returns the binary string representation of the UUID

public getBytes(): string

getFields

Returns the fields that comprise this UUID

public getFields(): \Ramsey\Uuid\Fields\FieldsInterface

getHex

Returns the hexadecimal representation of the UUID

public getHex(): \Ramsey\Uuid\Type\Hexadecimal

getInteger

Returns the integer representation of the UUID

public getInteger(): \Ramsey\Uuid\Type\Integer

getUrn

Returns the string standard representation of the UUID as a URN

public getUrn(): string

toString

Returns the string standard representation of the UUID

public toString(): string

getFactory

Returns the factory used to create UUIDs

public static getFactory(): \Ramsey\Uuid\UuidFactoryInterface
  • This method is static.

setFactory

Sets the factory used to create UUIDs

public static setFactory(\Ramsey\Uuid\UuidFactoryInterface $factory): void
  • This method is static.

Parameters:

Parameter Type Description
$factory \Ramsey\Uuid\UuidFactoryInterface A factory that will be used by this
class to create UUIDs

fromBytes

Creates a UUID from a byte string

public static fromBytes(string $bytes): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$bytes string A binary string

Return Value:

A UuidInterface instance created from a binary string representation

fromString

Creates a UUID from the string standard representation

public static fromString(string $uuid): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$uuid string A hexadecimal string

Return Value:

A UuidInterface instance created from a hexadecimal string representation

fromDateTime

Creates a UUID from a DateTimeInterface instance

public static fromDateTime(\DateTimeInterface $dateTime, \Ramsey\Uuid\Type\Hexadecimal|null $node = null, int|null $clockSeq = null): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$dateTime \DateTimeInterface The date and time
$node \Ramsey\Uuid\Type\Hexadecimal|null A 48-bit number representing the hardware
address
$clockSeq int|null A 14-bit number used to help avoid duplicates
that could arise when the clock is set backwards in time or if the
node ID changes

Return Value:

A UuidInterface instance that represents a version 1 UUID created from a DateTimeInterface instance

fromHexadecimal

Creates a UUID from the Hexadecimal object

public static fromHexadecimal(\Ramsey\Uuid\Type\Hexadecimal $hex): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$hex \Ramsey\Uuid\Type\Hexadecimal Hexadecimal object representing a hexadecimal number

Return Value:

A UuidInterface instance created from the Hexadecimal object representing a hexadecimal number

fromInteger

Creates a UUID from a 128-bit integer string

public static fromInteger(string $integer): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$integer string String representation of 128-bit integer

Return Value:

A UuidInterface instance created from the string representation of a 128-bit integer

isValid

Returns true if the provided string is a valid UUID

public static isValid(string $uuid): bool
  • This method is static.

Parameters:

Parameter Type Description
$uuid string A string to validate as a UUID

Return Value:

True if the string is a valid UUID, false otherwise

uuid1

Returns a version 1 (Gregorian time) UUID from a host ID, sequence number, and the current time

public static uuid1(\Ramsey\Uuid\Type\Hexadecimal|int|string|null $node = null, int|null $clockSeq = null): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$node \Ramsey\Uuid\Type\Hexadecimal|int|string|null A 48-bit number representing the
hardware address; this number may be represented as an integer or a
hexadecimal string
$clockSeq int|null A 14-bit number used to help avoid duplicates that
could arise when the clock is set backwards in time or if the node ID
changes

Return Value:

A UuidInterface instance that represents a version 1 UUID

uuid2

Returns a version 2 (DCE Security) UUID from a local domain, local identifier, host ID, clock sequence, and the current time

public static uuid2(int $localDomain, \Ramsey\Uuid\Type\Integer|null $localIdentifier = null, \Ramsey\Uuid\Type\Hexadecimal|null $node = null, int|null $clockSeq = null): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$localDomain int The local domain to use when generating bytes,
according to DCE Security
$localIdentifier \Ramsey\Uuid\Type\Integer|null The local identifier for the
given domain; this may be a UID or GID on POSIX systems, if the local
domain is person or group, or it may be a site-defined identifier
if the local domain is org
$node \Ramsey\Uuid\Type\Hexadecimal|null A 48-bit number representing the hardware
address
$clockSeq int|null A 14-bit number used to help avoid duplicates
that could arise when the clock is set backwards in time or if the
node ID changes (in a version 2 UUID, the lower 8 bits of this number
are replaced with the domain).

Return Value:

A UuidInterface instance that represents a version 2 UUID

uuid3

Returns a version 3 (name-based) UUID based on the MD5 hash of a namespace ID and a name

public static uuid3(string|\Ramsey\Uuid\UuidInterface $ns, string $name): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$ns string|\Ramsey\Uuid\UuidInterface The namespace (must be a valid UUID)
$name string The name to use for creating a UUID

Return Value:

A UuidInterface instance that represents a version 3 UUID

uuid4

Returns a version 4 (random) UUID

public static uuid4(): \Ramsey\Uuid\UuidInterface
  • This method is static.

Return Value:

A UuidInterface instance that represents a version 4 UUID

uuid5

Returns a version 5 (name-based) UUID based on the SHA-1 hash of a namespace ID and a name

public static uuid5(string|\Ramsey\Uuid\UuidInterface $ns, string $name): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$ns string|\Ramsey\Uuid\UuidInterface The namespace (must be a valid UUID)
$name string The name to use for creating a UUID

Return Value:

A UuidInterface instance that represents a version 5 UUID

uuid6

Returns a version 6 (reordered time) UUID from a host ID, sequence number, and the current time

public static uuid6(\Ramsey\Uuid\Type\Hexadecimal|null $node = null, int|null $clockSeq = null): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$node \Ramsey\Uuid\Type\Hexadecimal|null A 48-bit number representing the hardware
address
$clockSeq int|null A 14-bit number used to help avoid duplicates that
could arise when the clock is set backwards in time or if the node ID
changes

Return Value:

A UuidInterface instance that represents a version 6 UUID

uuid7

Returns a version 7 (Unix Epoch time) UUID

public static uuid7(\DateTimeInterface|null $dateTime = null): \Ramsey\Uuid\UuidInterface
  • This method is static.

Parameters:

Parameter Type Description
$dateTime \DateTimeInterface|null An optional date/time from which
to create the version 7 UUID. If not provided, the UUID is generated
using the current date/time.

Return Value:

A UuidInterface instance that represents a version 7 UUID

uuid8

Returns a version 8 (custom) UUID

public static uuid8(string $bytes): \Ramsey\Uuid\UuidInterface

The bytes provided may contain any value according to your application's needs. Be aware, however, that other applications may not understand the semantics of the value.

  • This method is static.

Parameters:

Parameter Type Description
$bytes string A 16-byte octet string. This is an open blob
of data that you may fill with 128 bits of information. Be aware,
however, bits 48 through 51 will be replaced with the UUID version
field, and bits 64 and 65 will be replaced with the UUID variant. You
MUST NOT rely on these bits for your application needs.

Return Value:

A UuidInterface instance that represents a version 8 UUID

Automatically generated on 2025-03-18