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c80e6aa7a4
Unless we're using the global source for math/rand, (*rand.Rand).Read should not be called concurrently. We seed the rng in daemon.Run to avoid ambiguity or hiding global side effects inside packages. closes #414
39 lines
677 B
Go
39 lines
677 B
Go
package trace
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import (
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"encoding/base64"
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"math/rand"
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"strings"
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"github.com/zrepl/zrepl/util/envconst"
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)
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var genIdNumBytes = envconst.Int("ZREPL_TRACE_ID_NUM_BYTES", 3)
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func init() {
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if genIdNumBytes < 1 {
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panic("trace node id byte length must be at least 1")
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}
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}
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func genID() string {
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var out strings.Builder
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enc := base64.NewEncoder(base64.RawStdEncoding, &out)
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buf := make([]byte, genIdNumBytes)
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for i := 0; i < len(buf); {
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n, err := rand.Read(buf[i:])
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if err != nil {
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panic(err)
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}
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i += n
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}
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n, err := enc.Write(buf[:])
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if err != nil || n != len(buf) {
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panic(err)
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}
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if err := enc.Close(); err != nil {
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panic(err)
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}
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return out.String()
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}
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