54 lines
923 B
Go
54 lines
923 B
Go
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package idgen
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import (
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"crypto/rand"
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"encoding/base32"
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"sync"
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"time"
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)
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// Creates a new, random token.
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func NewToken() string {
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buf := make([]byte, 20)
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_, err := rand.Read(buf)
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if err != nil {
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panic(err)
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}
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return base32.StdEncoding.EncodeToString(buf)
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}
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var (
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lock sync.Mutex
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ts int64 = time.Now().Unix()
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counter int64 = 1
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counterMax int64 = 1 << 20
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)
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// NextID can generate ~1M ints per second for a given nodeID.
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//
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// nodeID must be less than 64.
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func NextID(nodeID int64) int64 {
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lock.Lock()
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defer lock.Unlock()
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tt := time.Now().Unix()
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if tt > ts {
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ts = tt
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counter = 1
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} else {
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counter++
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if counter == counterMax {
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panic("Too many IDs.")
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}
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}
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return (ts << 26) + (nodeID << 20) + counter
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}
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func SplitID(id int64) (unixTime, nodeID, counter int64) {
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counter = id & (0x00000000000FFFFF)
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nodeID = (id >> 20) & (0x000000000000003F)
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unixTime = id >> 26
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return
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}
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