refactor: logparser v5 to pkgs

logparser/v5/pipe/groupers.go

@@ -0,0 +1,21 @@
+// For more tutorials: https://blog.learngoprogramming.com
+//
+// Copyright © 2018 Inanc Gumus
+// Learn Go Programming Course
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+//
+
+package pipe
+
+// DomainGrouper groups the records by domain.
+// It keeps the other fields intact.
+// For example: It returns the page field as well.
+// Exercise: Write a solution that removes the unnecessary data.
+func DomainGrouper(r Record) string {
+	return r.Domain
+}
+
+// Page groups records by page.
+func Page(r Record) string {
+	return r.Domain + r.Page
+}