Removing dependencies from pkg into Docker internal code

Closes #10922

Signed-off-by: Srini Brahmaroutu <srbrahma@us.ibm.com>

common/randomid.go

@@ -0,0 +1,38 @@
+package common
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"io"
+	"strconv"
+)
+
+// 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.
+func TruncateID(id string) string {
+	shortLen := 12
+	if len(id) < shortLen {
+		shortLen = len(id)
+	}
+	return id[:shortLen]
+}
+
+// GenerateRandomID returns an unique id
+func GenerateRandomID() string {
+	for {
+		id := make([]byte, 32)
+		if _, err := io.ReadFull(rand.Reader, id); 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
+		// used as a hostname. ref #3869
+		if _, err := strconv.ParseInt(TruncateID(value), 10, 64); err == nil {
+			continue
+		}
+		return value
+	}
+}