move: log parser

interfaces/log-parser/oop/report.go

@@ -0,0 +1,63 @@
+// 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 (
+	"errors"
+	"os"
+	"strings"
+)
+
+type resultFn func(result)
+
+type parser interface {
+	parse(resultFn) error
+}
+
+type analyser interface {
+	analyse(result)
+}
+
+type iterator interface {
+	each(resultFn)
+}
+
+type summarizer interface {
+	summarize(iterator) error
+}
+
+func report(p parser, a analyser, s summarizer) error {
+	if err := p.parse(a.analyse); err != nil {
+		return err
+	}
+
+	it, ok := a.(iterator)
+	if !ok {
+		return errors.New("cannot iterate on analyser")
+	}
+
+	return s.summarize(it)
+}
+
+// reportFromFile generates a default report
+func reportFromFile(path string) (err error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+
+	var p parser
+	switch {
+	case strings.HasSuffix(path, ".txt"):
+		p = newTextParser(f)
+	case strings.HasSuffix(path, ".json"):
+		p = newJSONParser(f)
+	}
+
+	return report(p, newAnalysis(), newTextSummary())
+}