Allow to execute multiple notifiers in parallel

Signed-off-by: Knut Ahlers <knut@ahlers.me>

main.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"git.luzifer.io/luzifer/birthday-notifier/pkg/dateutil"
+	"git.luzifer.io/luzifer/birthday-notifier/pkg/notifier"
 	"github.com/emersion/go-vcard"
 	"github.com/pkg/errors"
 	"github.com/robfig/cron/v3"
@@ -20,7 +21,7 @@ var (
 		FetchInterval       time.Duration `flag:"fetch-interval" default:"1h" description:"How often to fetch birthdays from CardDAV"`
 		LogLevel            string        `flag:"log-level" default:"info" description:"Log level (debug, info, warn, error, fatal)"`
 		NotifyDaysInAdvance []int         `flag:"notify-days-in-advance" default:"1" description:"Send notification X days before birthday"`
-		NotifyVia           string        `flag:"notify-via" default:"log" description:"How to send the notification (one of: log, pushover)"`
+		NotifyVia           []string      `flag:"notify-via" default:"log" description:"How to send the notification (one of: log, pushover)"`
 		WebdavBaseURL       string        `flag:"webdav-base-url" default:"" description:"Webdav server to connect to"`
 		WebdavPass          string        `flag:"webdav-pass" default:"" description:"Password for the Webdav user"`
 		WebdavPrincipal     string        `flag:"webdav-principal" default:"principals/users/%s" description:"Principal format to fetch the addressbooks for (%s will be replaced with the webdav-user)"`
@@ -60,10 +61,14 @@ func main() {
 		os.Exit(0)
 	}
 
-	notify := getNotifierByName(cfg.NotifyVia)
+	var notifiers []notifier.Notifier
+	for _, nv := range cfg.NotifyVia {
+		notify := getNotifierByName(nv)
 		if notify == nil {
 			logrus.Fatal("unknown notifier specified")
 		}
+		notifiers = append(notifiers, notify)
+	}
 
 	if birthdays, err = fetchBirthdays(); err != nil {
 		logrus.WithError(err).Fatal("initially fetching birthdays")
@@ -72,39 +77,12 @@ func main() {
 	crontab := cron.New()
 
 	// Periodically update birthdays
-	if _, err = crontab.AddFunc(fmt.Sprintf("@every %s", cfg.FetchInterval), func() {
-		birthdaysLock.Lock()
-		defer birthdaysLock.Unlock()
-
-		if birthdays, err = fetchBirthdays(); err != nil {
-			logrus.WithError(err).Error("updating birthdays")
-		}
-	}); err != nil {
+	if _, err = crontab.AddFunc(fmt.Sprintf("@every %s", cfg.FetchInterval), cronFetchBirthdays); err != nil {
 		logrus.WithError(err).Fatal("adding update-cron")
 	}
 
 	// Send notifications at midnight
-	if _, err = crontab.AddFunc("@midnight", func() {
-		birthdaysLock.Lock()
-		defer birthdaysLock.Unlock()
-
-		for _, b := range birthdays {
-			for _, advanceDays := range append(cfg.NotifyDaysInAdvance, 0) {
-				if !dateutil.IsToday(notifyDate(dateutil.ProjectToNextBirthday(b.birthday), advanceDays)) {
-					continue
-				}
-
-				go func(contact vcard.Card, when time.Time) {
-					if err = notify.SendNotification(contact, when); err != nil {
-						logrus.
-							WithError(err).
-							WithField("name", contact.Get(vcard.FieldFormattedName).Value).
-							Error("sending notification")
-					}
-				}(b.contact, b.birthday)
-			}
-		}
-	}); err != nil {
+	if _, err = crontab.AddFunc("@midnight", cronSendNotifications(notifiers)); err != nil {
 		logrus.WithError(err).Fatal("adding update-cron")
 	}
 
@@ -119,6 +97,42 @@ func main() {
 	}
 }
 
+func cronFetchBirthdays() {
+	birthdaysLock.Lock()
+	defer birthdaysLock.Unlock()
+
+	var err error
+	if birthdays, err = fetchBirthdays(); err != nil {
+		logrus.WithError(err).Error("updating birthdays")
+	}
+}
+
+func cronSendNotifications(notifiers []notifier.Notifier) func() {
+	return func() {
+		birthdaysLock.Lock()
+		defer birthdaysLock.Unlock()
+
+		for _, b := range birthdays {
+			for _, advanceDays := range append(cfg.NotifyDaysInAdvance, 0) {
+				if !dateutil.IsToday(notifyDate(dateutil.ProjectToNextBirthday(b.birthday), advanceDays)) {
+					continue
+				}
+
+				for i := range notifiers {
+					go func(n notifier.Notifier, contact vcard.Card, when time.Time) {
+						if err := n.SendNotification(contact, when); err != nil {
+							logrus.
+								WithError(err).
+								WithField("name", contact.Get(vcard.FieldFormattedName).Value).
+								Error("sending notification")
+						}
+					}(notifiers[i], b.contact, b.birthday)
+				}
+			}
+		}
+	}
+}
+
 func notifyDate(t time.Time, daysInAdvance int) time.Time {
 	return time.Date(t.Year(), t.Month(), t.Day()-daysInAdvance, 0, 0, 0, 0, time.Local)
 }