[feature] Implemented notification clear (#720)

* Implemented notification clear

* Added the cache clear mechanism

* added multi user check test

3 files changed, 45 insertions, 0 deletions

diff --git a/internal/db/bundb/notification.go b/internal/db/bundb/notification.go
index 5e825d096..034b3b8ec 100644
--- a/internal/db/bundb/notification.go
+++ b/internal/db/bundb/notification.go
@@ -108,3 +108,17 @@ func (n *notificationDB) GetNotifications(ctx context.Context, accountID string,
 
 	return notifs, nil
 }
+
+func (n *notificationDB) ClearNotifications(ctx context.Context, accountID string) db.Error {
+	if _, err := n.conn.
+		NewDelete().
+		Table("notifications").
+		Where("target_account_id = ?", accountID).
+		Exec(ctx); err != nil {
+		return n.conn.ProcessError(err)
+	}
+
+	n.cache.Clear()
+
+	return nil
+}
diff --git a/internal/db/bundb/notification_test.go b/internal/db/bundb/notification_test.go
index b14704dcc..d822c9a28 100644
--- a/internal/db/bundb/notification_test.go
+++ b/internal/db/bundb/notification_test.go
@@ -118,6 +118,35 @@ func (suite *NotificationTestSuite) TestGetNotificationsWithoutSpam() {
 	}
 }
 
+func (suite *NotificationTestSuite) TestClearNotificationsWithSpam() {
+	suite.spamNotifs()
+	testAccount := suite.testAccounts["local_account_1"]
+	err := suite.db.ClearNotifications(context.Background(), testAccount.ID)
+	suite.NoError(err)
+
+	notifications, err := suite.db.GetNotifications(context.Background(), testAccount.ID, 20, "ZZZZZZZZZZZZZZZZZZZZZZZZZZ", "00000000000000000000000000")
+	suite.NoError(err)
+	suite.NotNil(notifications)
+	suite.Empty(notifications)
+}
+
+func (suite *NotificationTestSuite) TestClearNotificationsWithTwoAccounts() {
+	suite.spamNotifs()
+	testAccount := suite.testAccounts["local_account_1"]
+	err := suite.db.ClearNotifications(context.Background(), testAccount.ID)
+	suite.NoError(err)
+
+	notifications, err := suite.db.GetNotifications(context.Background(), testAccount.ID, 20, "ZZZZZZZZZZZZZZZZZZZZZZZZZZ", "00000000000000000000000000")
+	suite.NoError(err)
+	suite.NotNil(notifications)
+	suite.Empty(notifications)
+
+	notif := []*gtsmodel.Notification{}
+	err = suite.db.GetAll(context.Background(), &notif)
+	suite.NoError(err)
+	suite.NotEmpty(notif)
+}
+
 func TestNotificationTestSuite(t *testing.T) {
 	suite.Run(t, new(NotificationTestSuite))
 }
diff --git a/internal/db/notification.go b/internal/db/notification.go
index d8291ae51..7d8258d93 100644
--- a/internal/db/notification.go
+++ b/internal/db/notification.go
@@ -32,4 +32,6 @@ type Notification interface {
 	GetNotifications(ctx context.Context, accountID string, limit int, maxID string, sinceID string) ([]*gtsmodel.Notification, Error)
 	// GetNotification returns one notification according to its id.
 	GetNotification(ctx context.Context, id string) (*gtsmodel.Notification, Error)
+	// ClearNotifications deletes every notification that pertain to the given accountID.
+	ClearNotifications(ctx context.Context, accountID string) Error
 }