Improve memory efficiency of noticesToBeSent by mapping pointers instead of WidNotice structs

mail.go

@@ -49,7 +49,7 @@ type SmtpSettings struct {
 	Password string `json:"password"`
 }
 
-func sendNotices(recipient string, notices []WidNotice, template MailTemplate, auth smtp.Auth, smtpConfig SmtpSettings, cache *map[string][]byte) error {
+func sendNotices(recipient string, notices []*WidNotice, template MailTemplate, auth smtp.Auth, smtpConfig SmtpSettings, cache *map[string][]byte) error {
 	logger.debug("Generating and sending mails for recipient " + recipient + " ...")
 	cacheHits := 0
 	cacheMisses := 0

main.go

@@ -121,16 +121,17 @@ func main() {
 		if len(newNotices) > 0 {
 			logger.info("Sending email notifications ...")
 			// mail recipient : pointer to slice of wid notices to be sent
-			noticesToBeSent := map[string][]WidNotice{}
+			noticesToBeSent := map[string][]*WidNotice{}
 			recipientsNotified := 0
 			var err error
 			for _, l := range *config.Lists {
 				// Filter notices for this list
 				for _, f := range l.Filter {
 					for _, n := range f.filter(newNotices) {
+						np := &n
 						for _, r := range l.Recipients {
-							if !noticeSliceContains(noticesToBeSent[r], n) {
-								noticesToBeSent[r] = append(noticesToBeSent[r], n)
+							if !noticeSliceContains(noticesToBeSent[r], np) {
+								noticesToBeSent[r] = append(noticesToBeSent[r], np)
 							}
 						}
 					}
@@ -138,7 +139,7 @@ func main() {
 			}
 			for r, notices := range noticesToBeSent {
 				// sort by publish date
-				slices.SortFunc(notices, func(a WidNotice, b WidNotice) int {
+				slices.SortFunc(notices, func(a *WidNotice, b *WidNotice) int {
 					if a.Published == b.Published {
 						return 0
 					} else if a.Published.After(b.Published) {

notice.go

@@ -25,7 +25,7 @@ type WidNotice struct {
 	PortalUrl string
 }
 
-func noticeSliceContains(notices []WidNotice, notice WidNotice) bool {
+func noticeSliceContains(notices []*WidNotice, notice *WidNotice) bool {
 	for _, x := range notices {
 		if x.Uuid == notice.Uuid {
 			return true

template.go

@@ -33,7 +33,7 @@ Sent by WidNotifier {{ .WidNotifierVersion }}
 `
 
 type TemplateData struct {
-	WidNotice
+	*WidNotice
 	WidNotifierVersion string
 }