simplify title setter with anon func

backend/app/store/service/service.go

@@ -76,14 +76,17 @@ func (s *DataStore) Create(comment store.Comment) (commentID string, err error)
 		return "", ErrRestrictedWordsFound
 	}
 
-	// keep input title and set to extracted if missing
-	if s.TitleExtractor != nil && comment.PostTitle == "" {
-		if title, err := s.TitleExtractor.Get(comment.Locator.URL); err == nil {
-			comment.PostTitle = title
-		} else {
-			log.Printf("[WARN] failed to set title, %v", err)
+	func() { // keep input title and set to extracted if missing
+		if s.TitleExtractor == nil || comment.PostTitle != "" {
+			return
 		}
-	}
+		title, e := s.TitleExtractor.Get(comment.Locator.URL)
+		if e != nil {
+			log.Printf("[WARN] failed to set title, %v", e)
+			return
+		}
+		comment.PostTitle = title
+	}()
 
 	return s.Interface.Create(comment)
 }

backend/app/store/service/title.go

@@ -53,7 +53,7 @@ func (t *TitleExtractor) Get(url string) (string, error) {
 		return title, nil
 	})
 
-	// on error save result (empty strung) to cache too but
+	// on error save result (empty string) to cache too and return "" title
 	if err != nil {
 		_, _ = t.cache.Get(url, func() (lcw.Value, error) { return "", nil })
 		return "", err

backend/app/store/service/title_test.go

@@ -1,6 +1,7 @@
 package service
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
@@ -84,7 +85,7 @@ func TestTitle_GetConcurrent(t *testing.T) {
 
 	for i := 0; i < 100; i++ {
 		i := i
-		g.Go(func() {
+		g.Go(func(_ context.Context) {
 			title, err := ex.Get(ts.URL + "/good/" + strconv.Itoa(i))
 			require.Nil(t, err)
 			assert.Equal(t, "blah 123 "+"/good/"+strconv.Itoa(i), title)