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Temptative patch to troubleshoot container id collision issue (updated at 15:15 UTC to add a mutex)
diff --git a/utils/utils.go b/utils/utils.go
index da6854b..0eb283a 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -2,12 +2,12 @@ package utils
import (
"bytes"
- "crypto/rand"
"crypto/sha1"
"crypto/sha256"
"encoding/hex"
"fmt"
"io"
+ "bufio"
"io/ioutil"
"net/http"
"os"
@@ -244,7 +244,7 @@ func GetTotalUsedFds() int {
// TruncateID returns a shorthand version of a string identifier for convenience.
// A collision with other shorthands is very unlikely, but possible.
// In case of a collision a lookup with TruncIndex.Get() will fail, and the caller
-// will need to use a langer prefix, or the full-length Id.
+// will need to use a larger prefix, or the full-length Id.
func TruncateID(id string) string {
shortLen := 12
if len(id) < shortLen {
@@ -253,16 +253,37 @@ func TruncateID(id string) string {
return id[:shortLen]
}
+var urandomMutex sync.Mutex
+
+func ReadRandomData(amount int) ([]byte, error) {
+ urandomMutex.Lock()
+ defer urandomMutex.Unlock()
+ file, err := os.Open("/dev/urandom")
+ if err != nil {
+ return nil, err
+ }
+ defer file.Close()
+
+ bytes := make([]byte, amount)
+ bufr := bufio.NewReader(file)
+ _,err = bufr.Read(bytes)
+ if err != nil {
+ return nil, err
+ }
+
+ return bytes, nil
+}
+
// GenerateRandomID returns an unique id
func GenerateRandomID() string {
for {
- id := make([]byte, 32)
- if _, err := io.ReadFull(rand.Reader, id); err != nil {
+ id, err := ReadRandomData(32);
+ if err != nil {
panic(err) // This shouldn't happen
}
value := hex.EncodeToString(id)
// if we try to parse the truncated for as an int and we don't have
- // an error then the value is all numberic and causes issues when
+ // an error then the value is all numeric and causes issues when
// used as a hostname. ref #3869
if _, err := strconv.ParseInt(TruncateID(value), 10, 64); err == nil {
continue
@rhatdan

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rhatdan commented Sep 19, 2014

Could this just be a multi-thread issue and you need to take a thread lock?

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