Refactor to make the maintanance simpler

- Fixed issue with webhooks

events/events_test.go

@@ -0,0 +1,29 @@
+package events
+
+import (
+	"bytes"
+	"encoding/json"
+	"testing"
+)
+
+func Test_newErrorEvent_with_invalid_code(t *testing.T) {
+	event := NewError(0, "The error message")
+
+	data, _ := json.Marshal(event)
+	expected := `{"event":"pusher:error","data":{"code":null,"message":"The error message"}}`
+
+	if bytes.Compare(data, []byte(expected)) != 0 {
+		t.Errorf("%s != %s", string(data), expected)
+	}
+}
+
+func Test_newErrorEvent_with_valid_code(t *testing.T) {
+	event := NewError(4007, "Unsupported protocol version")
+
+	data, _ := json.Marshal(event)
+	expected := `{"event":"pusher:error","data":{"code":4007,"message":"Unsupported protocol version"}}`
+
+	if bytes.Compare(data, []byte(expected)) != 0 {
+		t.Errorf("%s != %s", string(data), expected)
+	}
+}