add uuid v6, v7 #138
add uuid v6, v7 #138
Conversation
There was a problem hiding this comment.
There needs to be references to the standards being implemented. Are these official UUID versions that have been through any standards committee.
I don't see any unit tests for the generation of version 6 or version 7 uuids.
The test for version 7 really should verify that the right node and time is placed into the UUID. You can change timeNow to return a known time value so you can verify that the right bits are in the right places (version1 should really be tested this way as well, but that is outside your changes).
There is no reason for any changes in version4.go or util.go.
version4.go
Outdated
| @@ -9,15 +9,15 @@ import "io" | |||
| // New creates a new random UUID or panics. New is equivalent to | |||
| // the expression | |||
| // | |||
| // uuid.Must(uuid.NewRandom()) | |||
| // uuid.Must(uuid.NewRandom()) | |||
There was a problem hiding this comment.
This change impacts godoc, please do not change the formatting.
version4.go
Outdated
| func New() UUID { | ||
| return Must(NewRandom()) | ||
| } | ||
|
|
||
| // NewString creates a new random UUID and returns it as a string or panics. | ||
| // NewString is equivalent to the expression | ||
| // | ||
| // uuid.New().String() | ||
| // uuid.New().String() |
There was a problem hiding this comment.
This change impacts godoc, please do not change the formatting.
version4.go
Outdated
| // 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. |
There was a problem hiding this comment.
This change impacts godoc, please do not change the formatting.
util.go
Outdated
| @@ -41,3 +41,21 @@ func xtob(x1, x2 byte) (byte, bool) { | |||
| b2 := xvalues[x2] | |||
| return (b1 << 4) | b2, b1 != 255 && b2 != 255 | |||
| } | |||
|
|
|||
| // fill uuid (16byte) from poll | |||
| func fill16BytesFromPool(b []byte) error { | |||
There was a problem hiding this comment.
See comments from version4.go
version6.go
Outdated
| @@ -0,0 +1,36 @@ | |||
| // Copyright 2018 Google Inc. All rights reserved. | |||
version6.go
Outdated
| // or SetNodeInterface then it will be set automatically. If the NodeID cannot | ||
| // be set NewV6 returns nil. If clock sequence has not been set by | ||
| // SetClockSequence then it will be set automatically. If GetTime fails to | ||
| // return the current NewV6 returns nil and an error. |
There was a problem hiding this comment.
Please add a reference to the standard that defines Version 6 UUIDs.
version7.go
Outdated
| @@ -0,0 +1,70 @@ | |||
| // Copyright 2018 Google Inc. All rights reserved. | |||
| return uint64(sec*1000 + nsec/1000000), nil | ||
| } | ||
|
|
||
| func NewV7FromReader(r io.Reader) (UUID, error) { |
There was a problem hiding this comment.
This must have a godoc comment and also needs to reference the standard that defines version 7 UUIDs.
version7.go
Outdated
| } | ||
|
|
||
| // NewV7 returns a Version 7 UUID based on the current time. | ||
| // If GetTime fails to return the current NewV7 returns nil and an error. |
There was a problem hiding this comment.
It returns Nil, not nil, but only when it is unable to generate random data (see above while there will be no error in getting the current time).
| "encoding/binary" | ||
| "io" | ||
| ) | ||
|
|
There was a problem hiding this comment.
I believe the following functions can replace these functions:
func NewV7() (UUID, error) {
uuid, err := NewRandom()
if err != nil {
return uuid, err
}
makeV7(uuid[:])
return uuid, nil
}
func NewV7FromReader(r *io.Reader) (UUID, error) {
uuid, err := NewRandomFromReader(r)
if err != nil {
return uuid, err
}
makeV7(uuid[:])
return uuid, nil
}
func makeV7(uuid []byte) {
t := timeNow().UnixMilli()
uuid[0] = (t >> 40)
uuid[1] = (t >> 32)
uuid[2] = (t >> 24)
uuid[3] = (t >> 16)
uuid[4] = (t >> 8)
uuid[5] = t
uuid[6] = 0x70 | (uuid[6] & 0x0F)
}
They need comments, of course. Putting in the bytes directly rather than using binary.BigEndian.PutUint64 is quite a bit more efficient as you only put in 6 bytes, rather than 8, and PutUint64 fills in the bytes in the same way this code does.
Note that uuid[8] already has the right version number in it.
|
delete and recommit , see #139 |
add uuid version6， version7
https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03#variant_and_version_fields