refactor: logparser

interfaces/05-log-parser/oop/analysis.go

@@ -9,11 +9,6 @@ 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
@@ -29,9 +24,19 @@ func newAnalysis() *analysis {
 	}
 }
 
-func (a *analysis) groupBy(g groupFunc)   { a.groupKey = g }
-func (a *analysis) filterBy(f filterFunc) { a.filter = f }
+func (a *analysis) groupBy(g groupFunc) {
+	if g != nil {
+		a.groupKey = g
+	}
+}
 
+func (a *analysis) filterBy(f filterFunc) {
+	if f != nil {
+		a.filter = f
+	}
+}
+
+// analyse the given result
 func (a *analysis) analyse(r result) {
 	if !a.filter(r) {
 		return
@@ -45,11 +50,11 @@ func (a *analysis) analyse(r result) {
 	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)) {
+// each sends an analysis result to `handle`
+func (a *analysis) each(handle resultFn) {
 	sort.Strings(a.keys)
 
 	for _, domain := range a.keys {
-		f(a.sum[domain])
+		handle(a.sum[domain])
 	}
 }

interfaces/05-log-parser/oop/chartsummary.go

@@ -7,6 +7,9 @@ import (
 	c "github.com/wcharczuk/go-chart"
 )
 
+// You need to run:
+// go get -u github.com/wcharczuk/go-chart
+
 type chartSummary struct {
 	title         string
 	width, height int

interfaces/05-log-parser/oop/filters.go

@@ -2,6 +2,8 @@ package main
 
 import "strings"
 
+type filterFunc func(result) bool
+
 func noopFilter(r result) bool {
 	return true
 }

interfaces/05-log-parser/oop/groupers.go

@@ -1,5 +1,7 @@
 package main
 
+type groupFunc func(result) string
+
 // domainGrouper groups by domain.
 // but it keeps the other fields.
 // for example: it returns pages as well, but you shouldn't use them.

interfaces/05-log-parser/oop/jsonparser.go

@@ -15,18 +15,14 @@ import (
 )
 
 type jsonParser struct {
-	r      io.Reader
-	update func(r result)
+	r io.Reader
 }
 
 func newJSONParser(r io.Reader) *jsonParser {
-	return &jsonParser{
-		r:      r,
-		update: func(result) {},
-	}
+	return &jsonParser{r: r}
 }
 
-func (p *jsonParser) parse() error {
+func (p *jsonParser) parse(handle resultFn) error {
 	defer readClose(p.r)
 
 	bytes, err := ioutil.ReadAll(p.r)
@@ -34,10 +30,10 @@ func (p *jsonParser) parse() error {
 		return err
 	}
 
-	return p.parseJSON(bytes)
+	return parseJSON(bytes, handle)
 }
 
-func (p *jsonParser) parseJSON(bytes []byte) error {
+func parseJSON(bytes []byte, handle resultFn) error {
 	var rs []struct {
 		Domain  string
 		Page    string
@@ -53,7 +49,7 @@ func (p *jsonParser) parseJSON(bytes []byte) error {
 	}
 
 	for _, r := range rs {
-		p.update(result{
+		handle(result{
 			domain:  r.Domain,
 			page:    r.Page,
 			visits:  r.Visits,
@@ -63,7 +59,3 @@ func (p *jsonParser) parseJSON(bytes []byte) error {
 
 	return nil
 }
-
-func (p *jsonParser) notify(f func(r result)) {
-	p.update = f
-}

interfaces/05-log-parser/oop/main.go

@@ -9,31 +9,29 @@ package main
 
 import (
 	"log"
+	// "fmt"
 	"os"
 )
 
 func main() {
-	an := newAnalysis()
-	an.filterBy(notUsing(domainExtFilter("io", "com")))
-	an.groupBy(domainGrouper)
+	a := newAnalysis()
+	// a.filterBy(notUsing(domainExtFilter("io", "com")))
+	// a.groupBy(domainGrouper)
 
-	// pars, err := parseTextFile("log.txt")
-	// if err != nil {
-	// 	log.Fatalln(err)
-	// }
+	p := newTextParser(os.Stdin)
+	s := newTextSummary()
 
-	err := report(an, newTextParser(os.Stdin), summarizeFunc(textSummary))
-	// err := report(an, newJSONParser(os.Stdin), newTextSummary())
+	// s := &chartSummary{
+  	//  title:  "visits per domain",
+  	//  width:  1920,
+  	//  height: 800,
+  	// }
 
-	// chart := &chartSummary{
-	// 	title:  "visits per domain",
-	// 	width:  1920,
-	// 	height: 800,
-	// }
-
-	// err := report(an, newTextParser(os.Stdin), chart)
-
-	if err != nil {
+	if err := report(p, a, s); err != nil {
 		log.Fatalln(err)
 	}
+
+	// if err := reportFromFile(os.Args[1]); err != nil {
+	// 	log.Fatalln(err)
+	// }
 }

interfaces/05-log-parser/oop/report.go

@@ -7,34 +7,57 @@
 
 package main
 
-type notifier interface {
-	notify(func(r result))
-}
+import (
+	"errors"
+	"os"
+	"strings"
+)
+
+type resultFn func(result)
 
 type parser interface {
-	parse() error
-	notifier
-}
-
-type iterator interface {
-	each(func(result))
+	parse(resultFn) error
 }
 
 type analyser interface {
 	analyse(result)
-	iterator
+}
+
+type iterator interface {
+	each(resultFn)
 }
 
 type summarizer interface {
 	summarize(iterator) error
 }
 
-func report(a analyser, p parser, s summarizer) error {
-	p.notify(a.analyse)
-
-	if err := p.parse(); err != nil {
+func report(p parser, a analyser, s summarizer) error {
+	if err := p.parse(a.analyse); err != nil {
 		return err
 	}
 
-	return s.summarize(a)
+	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())
 }

interfaces/05-log-parser/oop/result.go

@@ -1,5 +1,7 @@
 package main
 
+const fieldsLength = 4
+
 type result struct {
 	domain  string
 	page    string

interfaces/05-log-parser/oop/textparser.go

@@ -11,39 +11,19 @@ import (
 	"bufio"
 	"fmt"
 	"io"
-	"os"
 	"strconv"
 	"strings"
 )
 
-const fieldsLength = 4
-
 type textParser struct {
-	r      io.Reader
-	update func(r result)
+	r io.Reader
 }
 
 func newTextParser(r io.Reader) *textParser {
-	return &textParser{
-		r:      r,
-		update: func(result) {},
-	}
+	return &textParser{r: r}
 }
 
-func parseTextFile(path string) (*textParser, error) {
-	f, err := os.Open(path)
-	if err != nil {
-		return nil, err
-	}
-
-	return newTextParser(f), nil
-}
-
-func (p *textParser) notify(f func(r result)) {
-	p.update = f
-}
-
-func (p *textParser) parse() error {
+func (p *textParser) parse(handle resultFn) error {
 	defer readClose(p.r)
 
 	var (
@@ -52,19 +32,19 @@ func (p *textParser) parse() error {
 	)
 
 	for in.Scan() {
-		r, err := p.parseFields(in.Text())
+		r, err := parseFields(in.Text())
 		if err != nil {
 			return fmt.Errorf("line %d: %v", l, err)
 		}
 
-		p.update(r)
+		handle(r)
 		l++
 	}
 
 	return in.Err()
 }
 
-func (p *textParser) parseFields(s string) (r result, err error) {
+func parseFields(s string) (r result, err error) {
 	fields := strings.Fields(s)
 	if len(fields) != fieldsLength {
 		return r, fmt.Errorf("wrong number of fields %q", fields)

interfaces/05-log-parser/oop/textsummary.go

@@ -21,20 +21,13 @@ const (
 	flags    = 0
 )
 
-type summarizeFunc func(iterator) error
+type textSummary struct{}
 
-func (f summarizeFunc) summarize(results iterator) error {
-	return f(results)
+func newTextSummary() *textSummary {
+	return new(textSummary)
 }
 
-// type textSummary struct{}
-
-// func newTextSummary() *textSummary {
-// 	return new(textSummary)
-// }
-
-// func (s *textSummary) summarize(results iterator) error {
-func textSummary(results iterator) error {
+func (s *textSummary) summarize(results iterator) error {
 	w := tabwriter.NewWriter(os.Stdout, minWidth, tabWidth, padding, ' ', flags)
 
 	write := fmt.Fprintf