Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

feat: func to generate V7 from custom time #175

Open
wants to merge 3 commits into
base: master
Choose a base branch
from
Open

feat: func to generate V7 from custom time #175

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
26baec7
feat: func to generate V7 from custom time
lazybark Nov 5, 2024
4decb2f
rename: NewV7FromTime => NewV7WithTime
lazybark Dec 1, 2024
a540b5d
rename: TestVersion7FromCustomTime => TestVersion7WithTime
lazybark Dec 1, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 25 additions & 0 deletions uuid_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -541,6 +541,31 @@ func TestRandomFromReader(t *testing.T) {
}
}

func TestVersion7FromCustomTime(t *testing.T) {
// Test with specific timestamp.
layout := "2006-01-02 15:04:05.000 -0700"

ts, err := time.Parse(layout, "2024-10-25 08:58:09.662 +0000")
if err != nil {
t.Fatalf("expected no error, got %v", err)
}

uuid, err := NewV7FromTime(ts)
if err != nil {
t.Fatalf("expected no error, got %v", err)
}

if len(uuid) != 16 {
t.Fatalf("expected UUID length of 16, got %d", len(uuid))
}

// Check if the timestamp part is correctly encoded.
expectedPrefix := "0192c2e5-bf7e-7000-"
if !strings.HasPrefix(uuid.String(), expectedPrefix) {
t.Fatalf("expected UUID to start with %s, got %s", expectedPrefix, uuid)
}
}

func TestRandPool(t *testing.T) {
myString := "8059ddhdle77cb52"
EnableRandPool()
Expand Down
59 changes: 35 additions & 24 deletions version7.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@ package uuid

import (
"io"
"time"
)

// UUID version 7 features a time-ordered value field derived from the widely
Expand All @@ -25,7 +26,7 @@ func NewV7() (UUID, error) {
if err != nil {
return uuid, err
}
makeV7(uuid[:])
makeV7(uuid[:], timeNow())
return uuid, nil
}

Expand All @@ -38,37 +39,47 @@ func NewV7FromReader(r io.Reader) (UUID, error) {
return uuid, err
}

makeV7(uuid[:])
makeV7(uuid[:], timeNow())
return uuid, nil
}

// NewV7FromTime returns a Version 7 UUID based on the provided time.
func NewV7FromTime(t time.Time) (UUID, error) {
lazybark marked this conversation as resolved.
Show resolved Hide resolved
uuid, err := NewRandom()
if err != nil {
return uuid, err
}
makeV7(uuid[:], t)
return uuid, nil
}

// makeV7 fill 48 bits time (uuid[0] - uuid[5]), set version b0111 (uuid[6])
// uuid[8] already has the right version number (Variant is 10)
// see function NewV7 and NewV7FromReader
func makeV7(uuid []byte) {
func makeV7(uuid []byte, t time.Time) {
/*
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| unix_ts_ms |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| unix_ts_ms | ver | rand_a (12 bit seq) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|var| rand_b |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| rand_b |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| unix_ts_ms |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| unix_ts_ms | ver | rand_a (12 bit seq) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|var| rand_b |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| rand_b |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
_ = uuid[15] // bounds check

t, s := getV7Time()
m, s := getV7TimeFromTime(t)

uuid[0] = byte(t >> 40)
uuid[1] = byte(t >> 32)
uuid[2] = byte(t >> 24)
uuid[3] = byte(t >> 16)
uuid[4] = byte(t >> 8)
uuid[5] = byte(t)
uuid[0] = byte(m >> 40)
uuid[1] = byte(m >> 32)
uuid[2] = byte(m >> 24)
uuid[3] = byte(m >> 16)
uuid[4] = byte(m >> 8)
uuid[5] = byte(m)

uuid[6] = 0x70 | (0x0F & byte(s>>8))
uuid[7] = byte(s)
Expand All @@ -82,14 +93,14 @@ var lastV7time int64

const nanoPerMilli = 1000000

// getV7Time returns the time in milliseconds and nanoseconds / 256.
// getV7TimeFromTime returns the time in milliseconds and nanoseconds / 256 for a custom time.
// The returned (milli << 12 + seq) is guaranteed to be greater than
// (milli << 12 + seq) returned by any previous call to getV7Time.
func getV7Time() (milli, seq int64) {
func getV7TimeFromTime(t time.Time) (milli, seq int64) {
timeMu.Lock()
defer timeMu.Unlock()

nano := timeNow().UnixNano()
nano := t.UnixNano()
milli = nano / nanoPerMilli
// Sequence number is between 0 and 3906 (nanoPerMilli>>8)
seq = (nano - milli*nanoPerMilli) >> 8
Expand Down