storj/satellite/metabase/rangedloop/uuid.go
Erik van Velzen c25391e976 satellite/metabase/rangedloop: uuid generation
Create helper function to generate ranges of UUIDs, for parallelizing
the segment loop.

Change-Id: I17dbc1d5effe27fc1a3491aa9ca56c692bd95df0
2022-10-31 16:05:41 +01:00

45 lines
1.0 KiB
Go

// Copyright (C) 2022 Storj Labs, Inc.
// See LICENSE for copying information.
package rangedloop
import (
"encoding/binary"
"storj.io/common/uuid"
)
// CreateUUIDBoundaries splits up the entire 128-bit UUID range into equal parts.
func CreateUUIDBoundaries(nRanges uint32) ([]uuid.UUID, error) {
if nRanges == 0 {
// every time this line is executed a mathematician feels a disturbance in the force
nRanges = 1
}
increment := uint32(1 << 32 / uint64(nRanges))
result := []uuid.UUID{}
for i := uint32(1); i < nRanges; i++ {
topBits := i * increment
newUuid, err := MakeUUIDWithTopBits(topBits)
if err != nil {
return nil, err
}
result = append(result, newUuid)
}
return result, nil
}
// MakeUUIDWithTopBits creates a zeroed UUID with the top 32 bits set from the input.
// Technically the result is not a UUID since it doesn't have the version and variant bits set.
func MakeUUIDWithTopBits(topBits uint32) (uuid.UUID, error) {
bytes := make([]byte, 16)
binary.BigEndian.PutUint32(bytes, topBits)
return uuid.FromBytes(bytes)
}