Add new PurgeOlderThan interface method to SQLite Database

base/database/controller.go

@@ -264,6 +264,20 @@ func (c *Controller) Purge(ctx context.Context, q *query.Query, local, internal
 	return 0, ErrNotImplemented
 }
 
+// PurgeOlderThan deletes all records last updated before the given time.
+// It returns the number of successful deletes and an error.
+func (c *Controller) PurgeOlderThan(ctx context.Context, prefix string, purgeBefore time.Time, local, internal bool) (int, error) {
+	if shuttingDown.IsSet() {
+		return 0, ErrShuttingDown
+	}
+
+	if purger, ok := c.storage.(storage.PurgeOlderThan); ok {
+		return purger.PurgeOlderThan(ctx, prefix, purgeBefore, local, internal, c.shadowDelete)
+	}
+
+	return 0, ErrNotImplemented
+}
+
 // Shutdown shuts down the storage.
 func (c *Controller) Shutdown() error {
 	return c.storage.Shutdown()

base/database/interface.go

@@ -562,6 +562,27 @@ func (i *Interface) Purge(ctx context.Context, q *query.Query) (int, error) {
 	return db.Purge(ctx, q, i.options.Local, i.options.Internal)
 }
 
+// PurgeOlderThan deletes all records last updated before the given time.
+// It returns the number of successful deletes and an error.
+func (i *Interface) PurgeOlderThan(ctx context.Context, prefix string, purgeBefore time.Time) (int, error) {
+	dbName, dbKeyPrefix := record.ParseKey(prefix)
+	if dbName == "" {
+		return 0, errors.New("unknown database")
+	}
+
+	db, err := getController(dbName)
+	if err != nil {
+		return 0, err
+	}
+
+	// Check if database is read only before we add to the cache.
+	if db.ReadOnly() {
+		return 0, ErrReadOnly
+	}
+
+	return db.PurgeOlderThan(ctx, dbKeyPrefix, purgeBefore, i.options.Local, i.options.Internal)
+}
+
 // Subscribe subscribes to updates matching the given query.
 func (i *Interface) Subscribe(q *query.Query) (*Subscription, error) {
 	_, err := q.Check()

base/database/storage/interface.go

@@ -46,3 +46,8 @@ type Batcher interface {
 type Purger interface {
 	Purge(ctx context.Context, q *query.Query, local, internal, shadowDelete bool) (int, error)
 }
+
+// PurgeOlderThan defines the database storage API for backends that support the PurgeOlderThan operation.
+type PurgeOlderThan interface {
+	PurgeOlderThan(ctx context.Context, prefix string, purgeBefore time.Time, local, internal, shadowDelete bool) (int, error)
+}

base/database/storage/sqlite/sqlite.go

@@ -401,24 +401,62 @@ func (db *SQLite) Purge(ctx context.Context, q *query.Query, local, internal, sh
 	}
 
 	// Otherwise, iterate over all entries and delete matching ones.
+
+	// TODO: Non-local, non-internal or content matching queries are not supported at the moment.
 	return 0, storage.ErrNotImplemented
+}
 
-	// Create iterator to check all matching records.
+// PurgeOlderThan deletes all records last updated before the given time. It returns the number of successful deletes and an error.
+func (db *SQLite) PurgeOlderThan(ctx context.Context, prefix string, purgeBefore time.Time, local, internal, shadowDelete bool) (int, error) {
+	db.wg.Add(1)
+	defer db.wg.Done()
 
-	// TODO: This is untested and also needs handling of shadowDelete.
-	// For now: Use only without where condition and with a local and internal db interface.
-	// queryIter := iterator.New()
-	// defer queryIter.Cancel()
-	// go db.queryExecutor(queryIter, q, local, internal)
+	purgeBeforeInt := purgeBefore.Unix()
 
-	// // Delete all matching records.
-	// var deleted int
-	// for r := range queryIter.Next {
-	// 	db.Delete(r.DatabaseKey())
-	// 	deleted++
-	// }
+	// Optimize for local and internal queries without where clause and without shadow delete.
+	if local && internal && !shadowDelete {
+		// First count entries (SQLite does not support affected rows)
+		n, err := models.Records.Query(
+			models.SelectWhere.Records.Key.Like(prefix+"%"),
+			models.SelectWhere.Records.Modified.LT(purgeBeforeInt),
+		).Count(db.ctx, db.bob)
+		if err != nil || n == 0 {
+			return int(n), err
+		}
 
-	// return deleted, nil
+		// Delete entries.
+		_, err = models.Records.Delete(
+			models.DeleteWhere.Records.Key.Like(prefix+"%"),
+			models.DeleteWhere.Records.Modified.LT(purgeBeforeInt),
+		).Exec(db.ctx, db.bob)
+		return int(n), err
+	}
+
+	// Optimize for local and internal queries without where clause, but with shadow delete.
+	if local && internal && shadowDelete {
+		// First count entries (SQLite does not support affected rows)
+		n, err := models.Records.Query(
+			models.SelectWhere.Records.Key.Like(prefix+"%"),
+			models.SelectWhere.Records.Modified.LT(purgeBeforeInt),
+		).Count(db.ctx, db.bob)
+		if err != nil || n == 0 {
+			return int(n), err
+		}
+
+		// Mark purged records as deleted.
+		now := time.Now().Unix()
+		_, err = models.Records.Update(
+			um.SetCol("format").ToArg(nil),
+			um.SetCol("value").ToArg(nil),
+			um.SetCol("deleted").ToArg(now),
+			models.UpdateWhere.Records.Key.Like(prefix+"%"),
+			models.UpdateWhere.Records.Modified.LT(purgeBeforeInt),
+		).Exec(db.ctx, db.bob)
+		return int(n), err
+	}
+
+	// TODO: Non-local or non-internal queries are not supported at the moment.
+	return 0, storage.ErrNotImplemented
 }
 
 // ReadOnly returns whether the database is read only.

base/database/storage/sqlite/sqlite_test.go

@@ -98,17 +98,24 @@ func TestSQLite(t *testing.T) {
 	qA := &TestRecord{}
 	qA.SetKey("test:path/to/A")
 	qA.UpdateMeta()
+
 	qB := &TestRecord{}
 	qB.SetKey("test:path/to/B")
 	qB.UpdateMeta()
+	// Set creation/modification in the past.
+	qB.Meta().Created = time.Now().Add(-time.Hour).Unix()
+	qB.Meta().Modified = time.Now().Add(-time.Hour).Unix()
+
 	qC := &TestRecord{}
 	qC.SetKey("test:path/to/C")
 	qC.UpdateMeta()
 	// Set expiry in the past.
 	qC.Meta().Expires = time.Now().Add(-time.Hour).Unix()
+
 	qZ := &TestRecord{}
 	qZ.SetKey("test:z")
 	qZ.UpdateMeta()
+
 	put, errs := db.PutMany(false)
 	put <- qA
 	put <- qB
@@ -150,6 +157,15 @@ func TestSQLite(t *testing.T) {
 		t.Fatal("should fail")
 	}
 
+	// purge older than
+	n, err := db.PurgeOlderThan(t.Context(), "path/to/", time.Now().Add(-30*time.Minute), true, true, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 1 {
+		t.Fatalf("unexpected purge older than delete count: %d", n)
+	}
+
 	// maintenance
 	err = db.MaintainRecordStates(t.Context(), time.Now().Add(-time.Minute), true)
 	if err != nil {
@@ -162,12 +178,12 @@ func TestSQLite(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	// purging
-	n, err := db.Purge(t.Context(), query.New("test:path/to/").MustBeValid(), true, true, true)
+	// purge
+	n, err = db.Purge(t.Context(), query.New("test:path/to/").MustBeValid(), true, true, true)
 	if err != nil {
 		t.Fatal(err)
 	}
-	if n != 2 {
+	if n != 1 {
 		t.Fatalf("unexpected purge delete count: %d", n)
 	}
 

service/intel/filterlists/updater.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/safing/portmaster/base/database"
 	"github.com/safing/portmaster/base/database/query"
+	"github.com/safing/portmaster/base/database/storage"
 	"github.com/safing/portmaster/base/log"
 	"github.com/safing/portmaster/base/updater"
 	"github.com/safing/portmaster/service/mgr"
@@ -158,9 +159,25 @@ func performUpdate(ctx context.Context) error {
 
 func removeAllObsoleteFilterEntries(wc *mgr.WorkerCtx) error {
 	log.Debugf("intel/filterlists: cleanup task started, removing obsolete filter list entries ...")
-	n, err := cache.Purge(wc.Ctx(), query.New(filterListKeyPrefix).Where(
-		// TODO(ppacher): remember the timestamp we started the last update
-		// and use that rather than "one hour ago"
+
+	// TODO: Remember the timestamp we started the last update and use that rather than "one hour ago".
+
+	// First try to purge with PurgeOlderThan.
+	n, err := cache.PurgeOlderThan(wc.Ctx(), filterListKeyPrefix, time.Now().Add(-time.Hour))
+	switch {
+	case err == nil:
+		// Success!
+		log.Debugf("intel/filterlists: successfully removed %d obsolete entries", n)
+		return nil
+	case errors.Is(err, database.ErrNotImplemented) || errors.Is(err, storage.ErrNotImplemented):
+		// Try next method.
+	default:
+		// Return error.
+		return err
+	}
+
+	// Try with regular purge.
+	n, err = cache.Purge(wc.Ctx(), query.New(filterListKeyPrefix).Where(
 		query.Where("UpdatedAt", query.LessThan, time.Now().Add(-time.Hour).Unix()),
 	))
 	if err != nil {