discovery service

api/pkg/discovery/instanceid_test.go

@@ -0,0 +1,53 @@
+package discovery
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+)
+
+func resetInstanceIDForTest() {
+	instanceID = ""
+	instanceOnce = sync.Once{}
+}
+
+func TestInstanceIDStable(t *testing.T) {
+	resetInstanceIDForTest()
+	original := instanceIDGenerator
+	defer func() {
+		instanceIDGenerator = original
+		resetInstanceIDForTest()
+	}()
+
+	instanceIDGenerator = func() string {
+		return "fixed-id"
+	}
+
+	first := InstanceID()
+	second := InstanceID()
+	if first != "fixed-id" || second != "fixed-id" {
+		t.Fatalf("expected stable instance id, got %q and %q", first, second)
+	}
+}
+
+func TestInstanceIDRegeneratesAfterReset(t *testing.T) {
+	resetInstanceIDForTest()
+	original := instanceIDGenerator
+	defer func() {
+		instanceIDGenerator = original
+		resetInstanceIDForTest()
+	}()
+
+	counter := 0
+	instanceIDGenerator = func() string {
+		counter++
+		return fmt.Sprintf("id-%d", counter)
+	}
+
+	first := InstanceID()
+	resetInstanceIDForTest()
+	second := InstanceID()
+	if first == second {
+		t.Fatalf("expected new instance id after reset, got %q", first)
+	}
+}