add: new interfaces

interfaces/oop/final/analysis.go

@@ -0,0 +1,55 @@
+// 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 main
+
+import "sort"
+
+type (
+	groupFunc  func(result) string
+	filterFunc func(result) bool
+)
+
+type analysis struct {
+	sum      map[string]result // metrics per domain
+	keys     []string          // unique keys
+	groupKey groupFunc
+	filter   filterFunc
+}
+
+func newAnalysis() *analysis {
+	return &analysis{
+		sum:      make(map[string]result),
+		groupKey: domainGrouper,
+		filter:   noopFilter,
+	}
+}
+
+func (a *analysis) groupBy(g groupFunc)   { a.groupKey = g }
+func (a *analysis) filterBy(f filterFunc) { a.filter = f }
+
+func (a *analysis) analyse(r result) {
+	if !a.filter(r) {
+		return
+	}
+
+	key := a.groupKey(r)
+	if _, ok := a.sum[key]; !ok {
+		a.keys = append(a.keys, key)
+	}
+
+	a.sum[key] = r.add(a.sum[key])
+}
+
+// each analysed result will be sent by the given func
+func (a *analysis) each(f func(r result)) {
+	sort.Strings(a.keys)
+
+	for _, domain := range a.keys {
+		f(a.sum[domain])
+	}
+}