Add nonce package for exchanges

exchanges/nonce/nonce.go

@@ -0,0 +1,49 @@
+package nonce
+
+import (
+	"strconv"
+	"sync"
+)
+
+// Nonce struct holds the nonce value
+type Nonce struct {
+	n   int64
+	mtx sync.Mutex
+}
+
+// Inc increments the nonce value
+func (n *Nonce) Inc() {
+	n.mtx.Lock()
+	n.n++
+	n.mtx.Unlock()
+}
+
+// Get retrives the nonce value
+func (n *Nonce) Get() int64 {
+	n.mtx.Lock()
+	defer n.mtx.Unlock()
+	return n.n
+}
+
+// GetInc increments and returns the value of the nonce
+func (n *Nonce) GetInc() int64 {
+	n.mtx.Lock()
+	defer n.mtx.Unlock()
+	n.n++
+	return n.n
+}
+
+// Set sets the nonce value
+func (n *Nonce) Set(val int64) {
+	n.mtx.Lock()
+	n.n = val
+	n.mtx.Unlock()
+}
+
+// Returns a string version of the nonce
+func (n *Nonce) String() string {
+	n.mtx.Lock()
+	result := strconv.FormatInt(n.n, 10)
+	n.mtx.Unlock()
+	return result
+}

exchanges/nonce/nonce_test.go

@@ -0,0 +1,75 @@
+package nonce
+
+import (
+	"testing"
+	"time"
+)
+
+func TestInc(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(1)
+	nonce.Inc()
+	expected := int64(2)
+	result := nonce.Get()
+	if result != expected {
+		t.Errorf("Test failed. Expected %d got %d", expected, result)
+	}
+}
+
+func TestGet(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(112321313)
+	expected := int64(112321313)
+	result := nonce.Get()
+	if expected != result {
+		t.Errorf("Test failed. Expected %d got %d", expected, result)
+	}
+}
+
+func TestGetInc(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(1)
+	expected := int64(2)
+	result := nonce.GetInc()
+	if expected != result {
+		t.Errorf("Test failed. Expected %d got %d", expected, result)
+	}
+}
+
+func TestSet(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(1)
+	expected := int64(1)
+	result := nonce.Get()
+	if expected != result {
+		t.Errorf("Test failed. Expected %d got %d", expected, result)
+	}
+}
+
+func TestString(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(12312313131)
+	expected := "12312313131"
+	result := nonce.String()
+	if expected != result {
+		t.Errorf("Test failed. Expected %s got %s", expected, result)
+	}
+}
+
+func TestNonceConcurrency(t *testing.T) {
+	var nonce Nonce
+	nonce.Set(12312)
+
+	for i := 0; i < 1000; i++ {
+		go nonce.Inc()
+	}
+
+	// Allow sufficient time for all routines to finish
+	time.Sleep(time.Second)
+
+	result := nonce.Get()
+	expected := int64(12312 + 1000)
+	if expected != result {
+		t.Errorf("Test failed. Expected %d got %d", expected, result)
+	}
+}