time now i called only when you run the service

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.1.0] - 2021-06-10
+### Changed
+- time is calculated only once
+
 ## [0.0.11] - 2021-06-05
 ### Changed
 - return to filepath as the best way to handle paths for different platforms.

internal/service/service.go

@@ -34,7 +34,7 @@ type OPDS struct {
 	AuthorURI   string
 }
 
-var TimeNowFunc = timeNow
+var TimeNow = timeNowFunc()
 
 func (s OPDS) Handler(w http.ResponseWriter, req *http.Request) error {
 	fPath := filepath.Join(s.DirRoot, req.URL.Path)
@@ -57,14 +57,14 @@ func (s OPDS) Handler(w http.ResponseWriter, req *http.Request) error {
 	}
 
 	content = append([]byte(xml.Header), content...)
-	http.ServeContent(w, req, "feed.xml", TimeNowFunc(), bytes.NewReader(content))
+	http.ServeContent(w, req, "feed.xml", TimeNow(), bytes.NewReader(content))
 	return nil
 }
 
 func (s OPDS) getContent(req *http.Request, dirpath string) (result []byte, err error) {
 	feed := s.makeFeed(dirpath, req)
 	if getPathType(dirpath) == pathTypeDirOfFiles {
-		acFeed := &opds.AcquisitionFeed{&feed, "http://purl.org/dc/terms/", "http://opds-spec.org/2010/catalog"}
+		acFeed := &opds.AcquisitionFeed{Feed: &feed, Dc: "http://purl.org/dc/terms/", Opds: "http://opds-spec.org/2010/catalog"}
 		result, err = xml.MarshalIndent(acFeed, "  ", "    ")
 	} else {
 		result, err = xml.MarshalIndent(feed, "  ", "    ")
@@ -79,7 +79,7 @@ func (s OPDS) makeFeed(dirpath string, req *http.Request) atom.Feed {
 		ID(req.URL.Path).
 		Title("Catalog in " + req.URL.Path).
 		Author(opds.AuthorBuilder.Name(s.Author).Email(s.AuthorEmail).URI(s.AuthorURI).Build()).
-		Updated(TimeNowFunc()).
+		Updated(TimeNow()).
 		AddLink(opds.LinkBuilder.Rel("start").Href("/").Type(navigationType).Build())
 
 	fis, _ := ioutil.ReadDir(dirpath)
@@ -89,8 +89,8 @@ func (s OPDS) makeFeed(dirpath string, req *http.Request) atom.Feed {
 			AddEntry(opds.EntryBuilder.
 				ID(req.URL.Path + fi.Name()).
 				Title(fi.Name()).
-				Updated(TimeNowFunc()).
-				Published(TimeNowFunc()).
+				Updated(TimeNow()).
+				Published(TimeNow()).
 				AddLink(opds.LinkBuilder.
 					Rel(getRel(fi.Name(), pathType)).
 					Title(fi.Name()).
@@ -153,6 +153,7 @@ func isFile(fi os.FileInfo) bool {
 	return !fi.IsDir()
 }
 
-func timeNow() time.Time {
-	return time.Now()
+func timeNowFunc() func() time.Time {
+	t := time.Now()
+	return func() time.Time { return t }
 }

internal/service/service_test.go

@@ -14,9 +14,9 @@ import (
 
 func TestHandler(t *testing.T) {
 	// pre-setup
-	nowFn := service.TimeNowFunc
+	nowFn := service.TimeNow
 	defer func() {
-		service.TimeNowFunc = nowFn
+		service.TimeNow = nowFn
 	}()
 
 	tests := map[string]struct {
@@ -36,7 +36,7 @@ func TestHandler(t *testing.T) {
 			s := service.OPDS{"testdata", "", "", ""}
 			w := httptest.NewRecorder()
 			req := httptest.NewRequest(http.MethodGet, tc.input, nil)
-			service.TimeNowFunc = func() time.Time {
+			service.TimeNow = func() time.Time {
 				return time.Date(2020, 05, 25, 00, 00, 00, 0, time.UTC)
 			}