added source to enable concurrent reproducible usage

uuid_source.go

@@ -0,0 +1,40 @@
+package uuid
+
+import (
+	"io"
+	"crypto/rand"
+)
+
+type UuidSource struct {
+	rander io.Reader
+}
+
+func NewSource(r io.Reader) UuidSource {
+	var uuidSource UuidSource
+	uuidSource.SetRand(r)
+	return uuidSource
+
+}
+
+func (uuidSource *UuidSource) SetRand(r io.Reader) {
+	if r == nil {
+		uuidSource.rander = rand.Reader
+		return
+	}
+	uuidSource.rander = r
+}
+
+func (uuidSource UuidSource) NewRandom() (UUID, error) {
+	var uuid UUID
+	_, err := io.ReadFull(uuidSource.rander, uuid[:])
+	if err != nil {
+		return Nil, err
+	}
+	uuid[6] = (uuid[6] & 0x0f) | 0x40 // Version 4
+	uuid[8] = (uuid[8] & 0x3f) | 0x80 // Variant is 10
+	return uuid, nil
+}
+
+func (uuidSource UuidSource) New() UUID {
+	return Must(uuidSource.NewRandom())
+}

uuid_source_test.go

@@ -0,0 +1,55 @@
+package uuid
+
+import (
+	"testing"
+	"fmt"
+	"strings"
+	"math/rand"
+
+)
+
+func TestUuidSources(t *testing.T) {
+
+	uuidSourceA := NewSource(rand.New(rand.NewSource(34576)))
+	uuidSourceB := NewSource(rand.New(rand.NewSource(34576)))
+
+	var uuidStrA, uuidStrB string
+	fmt.Printf("Random values: ")
+	for i := 0; i < 10; i++ {
+		uuidStrA += uuidSourceA.New().String() + "."
+	}
+	fmt.Printf("%v\n", uuidStrA)
+
+	fmt.Printf("Random values: ")
+	for i := 0; i < 10; i++ {
+		uuidStrB += uuidSourceB.New().String() + "."
+	}
+	fmt.Printf("%v\n", uuidStrB)
+
+	if !strings.EqualFold(uuidStrA, uuidStrB) {
+		t.Error("Uuid values are not reproducaible!")
+	}
+
+	uuidSourceA = NewSource(rand.New(rand.NewSource(66)))
+	uuidSourceB = NewSource(rand.New(rand.NewSource(77)))
+
+
+	uuidStrA = ""
+	uuidStrB = ""
+	fmt.Printf("Random values: ")
+	for i := 0; i < 10; i++ {
+		uuidStrA += uuidSourceA.New().String() + "."
+	}
+	fmt.Printf("%v\n", uuidStrA)
+
+	fmt.Printf("Random values: ")
+	for i := 0; i < 10; i++ {
+		uuidStrB += uuidSourceB.New().String() + "."
+	}
+	fmt.Printf("%v\n", uuidStrB)
+
+	if strings.EqualFold(uuidStrA, uuidStrB) {
+		t.Error("Uuid values should not be reproducaible!")
+	}
+
+}