Add housekeeping function to delete old/expired EDUs (#2399)

* Add housekeeping function to delete old/expired EDUs

* Add migrations

* Evict EDUs from cache

* Fix queries

* Fix upgrade

* Use map[string]time.Duration to specify different expiry times

* Fix copy & paste mistake

* Set expires_at to tomorrow

* Don't allow NULL

* Add comment

* Add tests

* Use new testrig package

* Fix migrations

* Never expire m.direct_to_device

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>
Co-authored-by: kegsay <kegan@matrix.org>

3 files changed, 148 insertions, 23 deletions

diff --git a/federationapi/storage/sqlite3/deltas/2022042812473400_addexpiresat.go b/federationapi/storage/sqlite3/deltas/2022042812473400_addexpiresat.go
new file mode 100644
index 00000000..c5030163
--- /dev/null
+++ b/federationapi/storage/sqlite3/deltas/2022042812473400_addexpiresat.go
@@ -0,0 +1,68 @@
+// Copyright 2022 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package deltas
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"time"
+
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+func UpAddexpiresat(ctx context.Context, tx *sql.Tx) error {
+	_, err := tx.ExecContext(ctx, "ALTER TABLE federationsender_queue_edus RENAME TO federationsender_queue_edus_old;")
+	if err != nil {
+		return fmt.Errorf("failed to rename table: %w", err)
+	}
+
+	_, err = tx.ExecContext(ctx, `
+CREATE TABLE IF NOT EXISTS federationsender_queue_edus (
+	edu_type TEXT NOT NULL,
+	server_name TEXT NOT NULL,
+	json_nid BIGINT NOT NULL,
+	expires_at BIGINT NOT NULL DEFAULT 0
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS federationsender_queue_edus_json_nid_idx
+    ON federationsender_queue_edus (json_nid, server_name);
+`)
+	if err != nil {
+		return fmt.Errorf("failed to create new table: %w", err)
+	}
+	_, err = tx.ExecContext(ctx, `
+INSERT
+    INTO federationsender_queue_edus (
+        edu_type, server_name, json_nid, expires_at
+    )  SELECT edu_type, server_name, json_nid, 0 FROM federationsender_queue_edus_old;
+`)
+	if err != nil {
+		return fmt.Errorf("failed to update queue_edus: %w", err)
+	}
+	_, err = tx.ExecContext(ctx, "UPDATE federationsender_queue_edus SET expires_at = $1 WHERE edu_type != 'm.direct_to_device'", gomatrixserverlib.AsTimestamp(time.Now().Add(time.Hour*24)))
+	if err != nil {
+		return fmt.Errorf("failed to update queue_edus: %w", err)
+	}
+	return nil
+}
+
+func DownAddexpiresat(ctx context.Context, tx *sql.Tx) error {
+	_, err := tx.ExecContext(ctx, "ALTER TABLE federationsender_queue_edus DROP COLUMN expires_at;")
+	if err != nil {
+		return fmt.Errorf("failed to rename table: %w", err)
+	}
+	return nil
+}
diff --git a/federationapi/storage/sqlite3/queue_edus_table.go b/federationapi/storage/sqlite3/queue_edus_table.go
index f4c84f09..8e7e7901 100644
--- a/federationapi/storage/sqlite3/queue_edus_table.go
+++ b/federationapi/storage/sqlite3/queue_edus_table.go
@@ -20,9 +20,11 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/matrix-org/gomatrixserverlib"
+
+	"github.com/matrix-org/dendrite/federationapi/storage/sqlite3/deltas"
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
-	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const queueEDUsSchema = `
@@ -32,7 +34,9 @@ CREATE TABLE IF NOT EXISTS federationsender_queue_edus (
     -- The domain part of the user ID the EDU event is for.
 	server_name TEXT NOT NULL,
 	-- The JSON NID from the federationsender_queue_edus_json table.
-	json_nid BIGINT NOT NULL
+	json_nid BIGINT NOT NULL,
+	-- The expiry time of this edu, if any.
+	expires_at BIGINT NOT NULL DEFAULT 0
 );
 
 CREATE UNIQUE INDEX IF NOT EXISTS federationsender_queue_edus_json_nid_idx
@@ -44,8 +48,8 @@ CREATE INDEX IF NOT EXISTS federationsender_queue_edus_server_name_idx
 `
 
 const insertQueueEDUSQL = "" +
-	"INSERT INTO federationsender_queue_edus (edu_type, server_name, json_nid)" +
-	" VALUES ($1, $2, $3)"
+	"INSERT INTO federationsender_queue_edus (edu_type, server_name, json_nid, expires_at)" +
+	" VALUES ($1, $2, $3, $4)"
 
 const deleteQueueEDUsSQL = "" +
 	"DELETE FROM federationsender_queue_edus WHERE server_name = $1 AND json_nid IN ($2)"
@@ -66,13 +70,22 @@ const selectQueueEDUCountSQL = "" +
 const selectQueueServerNamesSQL = "" +
 	"SELECT DISTINCT server_name FROM federationsender_queue_edus"
 
+const selectExpiredEDUsSQL = "" +
+	"SELECT DISTINCT json_nid FROM federationsender_queue_edus WHERE expires_at > 0 AND expires_at <= $1"
+
+const deleteExpiredEDUsSQL = "" +
+	"DELETE FROM federationsender_queue_edus WHERE expires_at > 0 AND expires_at <= $1"
+
 type queueEDUsStatements struct {
-	db                                   *sql.DB
-	insertQueueEDUStmt                   *sql.Stmt
+	db                 *sql.DB
+	insertQueueEDUStmt *sql.Stmt
+	// deleteQueueEDUStmt                *sql.Stmt - prepared at runtime due to variadic
 	selectQueueEDUStmt                   *sql.Stmt
 	selectQueueEDUReferenceJSONCountStmt *sql.Stmt
 	selectQueueEDUCountStmt              *sql.Stmt
 	selectQueueEDUServerNamesStmt        *sql.Stmt
+	selectExpiredEDUsStmt                *sql.Stmt
+	deleteExpiredEDUsStmt                *sql.Stmt
 }
 
 func NewSQLiteQueueEDUsTable(db *sql.DB) (s *queueEDUsStatements, err error) {
@@ -81,24 +94,33 @@ func NewSQLiteQueueEDUsTable(db *sql.DB) (s *queueEDUsStatements, err error) {
 	}
 	_, err = db.Exec(queueEDUsSchema)
 	if err != nil {
-		return
-	}
-	if s.insertQueueEDUStmt, err = db.Prepare(insertQueueEDUSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUStmt, err = db.Prepare(selectQueueEDUSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUReferenceJSONCountStmt, err = db.Prepare(selectQueueEDUReferenceJSONCountSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUCountStmt, err = db.Prepare(selectQueueEDUCountSQL); err != nil {
-		return
+		return s, err
 	}
-	if s.selectQueueEDUServerNamesStmt, err = db.Prepare(selectQueueServerNamesSQL); err != nil {
-		return
+
+	m := sqlutil.NewMigrator(db)
+	m.AddMigrations(
+		sqlutil.Migration{
+			Version: "federationapi: add expiresat column",
+			Up:      deltas.UpAddexpiresat,
+		},
+	)
+	if err := m.Up(context.Background()); err != nil {
+		return s, err
 	}
-	return
+
+	return s, nil
+}
+
+func (s *queueEDUsStatements) Prepare() error {
+	return sqlutil.StatementList{
+		{&s.insertQueueEDUStmt, insertQueueEDUSQL},
+		{&s.selectQueueEDUStmt, selectQueueEDUSQL},
+		{&s.selectQueueEDUReferenceJSONCountStmt, selectQueueEDUReferenceJSONCountSQL},
+		{&s.selectQueueEDUCountStmt, selectQueueEDUCountSQL},
+		{&s.selectQueueEDUServerNamesStmt, selectQueueServerNamesSQL},
+		{&s.selectExpiredEDUsStmt, selectExpiredEDUsSQL},
+		{&s.deleteExpiredEDUsStmt, deleteExpiredEDUsSQL},
+	}.Prepare(s.db)
 }
 
 func (s *queueEDUsStatements) InsertQueueEDU(
@@ -107,6 +129,7 @@ func (s *queueEDUsStatements) InsertQueueEDU(
 	eduType string,
 	serverName gomatrixserverlib.ServerName,
 	nid int64,
+	expiresAt gomatrixserverlib.Timestamp,
 ) error {
 	stmt := sqlutil.TxStmt(txn, s.insertQueueEDUStmt)
 	_, err := stmt.ExecContext(
@@ -114,6 +137,7 @@ func (s *queueEDUsStatements) InsertQueueEDU(
 		eduType,    // the EDU type
 		serverName, // destination server name
 		nid,        // JSON blob NID
+		expiresAt,  // timestamp of expiry
 	)
 	return err
 }
@@ -159,7 +183,7 @@ func (s *queueEDUsStatements) SelectQueueEDUs(
 		}
 		result = append(result, nid)
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *queueEDUsStatements) SelectQueueEDUReferenceJSONCount(
@@ -209,3 +233,33 @@ func (s *queueEDUsStatements) SelectQueueEDUServerNames(
 
 	return result, rows.Err()
 }
+
+func (s *queueEDUsStatements) SelectExpiredEDUs(
+	ctx context.Context, txn *sql.Tx,
+	expiredBefore gomatrixserverlib.Timestamp,
+) ([]int64, error) {
+	stmt := sqlutil.TxStmt(txn, s.selectExpiredEDUsStmt)
+	rows, err := stmt.QueryContext(ctx, expiredBefore)
+	if err != nil {
+		return nil, err
+	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectExpiredEDUs: rows.close() failed")
+	var result []int64
+	var nid int64
+	for rows.Next() {
+		if err = rows.Scan(&nid); err != nil {
+			return nil, err
+		}
+		result = append(result, nid)
+	}
+	return result, rows.Err()
+}
+
+func (s *queueEDUsStatements) DeleteExpiredEDUs(
+	ctx context.Context, txn *sql.Tx,
+	expiredBefore gomatrixserverlib.Timestamp,
+) error {
+	stmt := sqlutil.TxStmt(txn, s.deleteExpiredEDUsStmt)
+	_, err := stmt.ExecContext(ctx, expiredBefore)
+	return err
+}
diff --git a/federationapi/storage/sqlite3/storage.go b/federationapi/storage/sqlite3/storage.go
index 9594aaec..c89cb6be 100644
--- a/federationapi/storage/sqlite3/storage.go
+++ b/federationapi/storage/sqlite3/storage.go
@@ -90,6 +90,9 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 	if err != nil {
 		return nil, err
 	}
+	if err = queueEDUs.Prepare(); err != nil {
+		return nil, err
+	}
 	d.Database = shared.Database{
 		DB:                       d.db,
 		ServerName:               serverName,