Add ability to set provider group

pkg/etw/sample/sample.go

@@ -16,6 +16,12 @@ func callback(sourceID guid.GUID, state etw.ProviderState, level etw.Level, matc
 }
 
 func main() {
+	group, err := guid.FromString("12341234-abcd-abcd-abcd-123412341234")
+	if err != nil {
+		logrus.Error(err)
+		return
+	}
+
 	provider, err := etw.NewProvider("TestProvider", callback)
 
 	if err != nil {
@@ -28,7 +34,20 @@ func main() {
 		}
 	}()
 
+	providerWithGroup, err := etw.NewProviderWithGroup("TestProviderWithGroup", group, callback)
+
+	if err != nil {
+		logrus.Error(err)
+		return
+	}
+	defer func() {
+		if err := providerWithGroup.Close(); err != nil {
+			logrus.Error(err)
+		}
+	}()
+
 	fmt.Printf("Provider ID: %s\n", provider)
+	fmt.Printf("Provider w/ Group ID: %s\n", providerWithGroup)
 
 	reader := bufio.NewReader(os.Stdin)
 
@@ -58,4 +77,28 @@ func main() {
 		logrus.Error(err)
 		return
 	}
+
+	if err := providerWithGroup.WriteEvent(
+		"TestEventWithGroup",
+		etw.WithEventOpts(
+			etw.WithLevel(etw.LevelInfo),
+			etw.WithKeyword(0x140),
+		),
+		etw.WithFields(
+			etw.StringField("TestField", "Foo"),
+			etw.StringField("TestField2", "Bar"),
+			etw.Struct("TestStruct",
+				etw.StringField("Field1", "Value1"),
+				etw.StringField("Field2", "Value2")),
+			etw.StringArray("TestArray", []string{
+				"Item1",
+				"Item2",
+				"Item3",
+				"Item4",
+				"Item5",
+			})),
+	); err != nil {
+		logrus.Error(err)
+		return
+	}
 }