Outbound live stream notifications (#1663)

* First pass at browser, discord, twilio notifications

* Commit updated Javascript packages

* Remove twilio notification support

* Email notifications/smtp support

* Fix Firefox notification support, remove chrome checks

* WIP more email work

* Add support for twitter notifications

* Add stream title to discord and twitter notifications

* Update notification registration modal

* Fix hide/show email section

* Commit updated API documentation

* Commit updated Javascript packages

* Fix post-rebase missing var

* Remove unused var

* Handle unsubscribe errors for browser push

* Standardize email config prop names

* Allow overriding go live email template

* Some notifications cleanup

* Commit updated Javascript packages

* Remove email/smtp/mailjet support

* Remove more references to email notifications

Co-authored-by: Owncast <owncast@owncast.online>

notifications/persistence.go

@@ -0,0 +1,60 @@
+package notifications
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/owncast/owncast/core/data"
+	"github.com/owncast/owncast/db"
+	"github.com/pkg/errors"
+	log "github.com/sirupsen/logrus"
+)
+
+func createNotificationsTable(db *sql.DB) {
+	log.Traceln("Creating federation followers table...")
+
+	createTableSQL := `CREATE TABLE IF NOT EXISTS notifications (
+    "id" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+		"channel" TEXT NOT NULL,
+		"destination" TEXT NOT NULL,
+		"created_at" TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
+		CREATE INDEX channel_index ON notifications (channel);`
+
+	stmt, err := db.Prepare(createTableSQL)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer stmt.Close()
+	_, err = stmt.Exec()
+	if err != nil {
+		log.Warnln("error executing sql creating followers table", createTableSQL, err)
+	}
+}
+
+// AddNotification saves a new user notification destination.
+func AddNotification(channel, destination string) error {
+	return data.GetDatastore().GetQueries().AddNotification(context.Background(), db.AddNotificationParams{
+		Channel:     channel,
+		Destination: destination,
+	})
+}
+
+// RemoveNotificationForChannel removes a notification destination..
+func RemoveNotificationForChannel(channel, destination string) error {
+	log.Println("Removing notification for channel", channel)
+	return data.GetDatastore().GetQueries().RemoveNotificationDestinationForChannel(context.Background(), db.RemoveNotificationDestinationForChannelParams{
+		Channel:     channel,
+		Destination: destination,
+	})
+}
+
+// GetNotificationDestinationsForChannel will return a collection of
+// destinations to notify for a given channel.
+func GetNotificationDestinationsForChannel(channel string) ([]string, error) {
+	result, err := data.GetDatastore().GetQueries().GetNotificationDestinationsForChannel(context.Background(), channel)
+	if err != nil {
+		return nil, errors.Wrap(err, "unable to query notification destinations for channel "+channel)
+	}
+
+	return result, nil
+}