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>

federationapi/federationapi.go

@@ -15,6 +15,8 @@
 package federationapi
 
 import (
+	"time"
+
 	"github.com/gorilla/mux"
 	"github.com/matrix-org/dendrite/federationapi/api"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
@@ -167,5 +169,16 @@ func NewInternalAPI(
 	if err = presenceConsumer.Start(); err != nil {
 		logrus.WithError(err).Panic("failed to start presence consumer")
 	}
+
+	var cleanExpiredEDUs func()
+	cleanExpiredEDUs = func() {
+		logrus.Infof("Cleaning expired EDUs")
+		if err := federationDB.DeleteExpiredEDUs(base.Context()); err != nil {
+			logrus.WithError(err).Error("Failed to clean expired EDUs")
+		}
+		time.AfterFunc(time.Hour, cleanExpiredEDUs)
+	}
+	time.AfterFunc(time.Minute, cleanExpiredEDUs)
+
 	return internal.NewFederationInternalAPI(federationDB, cfg, rsAPI, federation, stats, caches, queues, keyRing)
 }

federationapi/queue/destinationqueue.go

@@ -127,6 +127,7 @@ func (oq *destinationQueue) sendEDU(event *gomatrixserverlib.EDU, receipt *share
 		oq.destination, // the destination server name
 		receipt,        // NIDs from federationapi_queue_json table
 		event.Type,
+		nil, // this will use the default expireEDUTypes map
 	); err != nil {
 		logrus.WithError(err).Errorf("failed to associate EDU with destination %q", oq.destination)
 		return

federationapi/storage/interface.go

@@ -16,6 +16,7 @@ package storage
 
 import (
 	"context"
+	"time"
 
 	"github.com/matrix-org/dendrite/federationapi/storage/shared"
 	"github.com/matrix-org/dendrite/federationapi/types"
@@ -38,7 +39,7 @@ type Database interface {
 	GetPendingEDUs(ctx context.Context, serverName gomatrixserverlib.ServerName, limit int) (edus map[*shared.Receipt]*gomatrixserverlib.EDU, err error)
 
 	AssociatePDUWithDestination(ctx context.Context, transactionID gomatrixserverlib.TransactionID, serverName gomatrixserverlib.ServerName, receipt *shared.Receipt) error
-	AssociateEDUWithDestination(ctx context.Context, serverName gomatrixserverlib.ServerName, receipt *shared.Receipt, eduType string) error
+	AssociateEDUWithDestination(ctx context.Context, serverName gomatrixserverlib.ServerName, receipt *shared.Receipt, eduType string, expireEDUTypes map[string]time.Duration) error
 
 	CleanPDUs(ctx context.Context, serverName gomatrixserverlib.ServerName, receipts []*shared.Receipt) error
 	CleanEDUs(ctx context.Context, serverName gomatrixserverlib.ServerName, receipts []*shared.Receipt) error
@@ -70,4 +71,6 @@ type Database interface {
 	// Query the notary for the server keys for the given server. If `optKeyIDs` is not empty, multiple server keys may be returned (between 1 - len(optKeyIDs))
 	// such that the combination of all server keys will include all the `optKeyIDs`.
 	GetNotaryKeys(ctx context.Context, serverName gomatrixserverlib.ServerName, optKeyIDs []gomatrixserverlib.KeyID) ([]gomatrixserverlib.ServerKeys, error)
+	// DeleteExpiredEDUs cleans up expired EDUs
+	DeleteExpiredEDUs(ctx context.Context) error
 }

federationapi/storage/postgres/deltas/2022042812473400_addexpiresat.go

@@ -0,0 +1,44 @@
+// 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 ADD COLUMN IF NOT EXISTS expires_at BIGINT NOT NULL DEFAULT 0;")
+	if err != nil {
+		return fmt.Errorf("failed to execute upgrade: %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 execute downgrade: %w", err)
+	}
+	return nil
+}

federationapi/storage/postgres/queue_edus_table.go

@@ -19,9 +19,11 @@ import (
 	"database/sql"
 
 	"github.com/lib/pq"
+	"github.com/matrix-org/gomatrixserverlib"
+
+	"github.com/matrix-org/dendrite/federationapi/storage/postgres/deltas"
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
-	"github.com/matrix-org/gomatrixserverlib"
 )
 
 const queueEDUsSchema = `
@@ -31,7 +33,9 @@ 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
@@ -43,8 +47,8 @@ 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 deleteQueueEDUSQL = "" +
 	"DELETE FROM federationsender_queue_edus WHERE server_name = $1 AND json_nid = ANY($2)"
@@ -65,6 +69,12 @@ 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
@@ -73,6 +83,8 @@ type queueEDUsStatements struct {
 	selectQueueEDUReferenceJSONCountStmt *sql.Stmt
 	selectQueueEDUCountStmt              *sql.Stmt
 	selectQueueEDUServerNamesStmt        *sql.Stmt
+	selectExpiredEDUsStmt                *sql.Stmt
+	deleteExpiredEDUsStmt                *sql.Stmt
 }
 
 func NewPostgresQueueEDUsTable(db *sql.DB) (s *queueEDUsStatements, err error) {
@@ -81,27 +93,34 @@ func NewPostgresQueueEDUsTable(db *sql.DB) (s *queueEDUsStatements, err error) {
 	}
 	_, err = s.db.Exec(queueEDUsSchema)
 	if err != nil {
-		return
+		return s, err
 	}
-	if s.insertQueueEDUStmt, err = s.db.Prepare(insertQueueEDUSQL); 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
 	}
-	if s.deleteQueueEDUStmt, err = s.db.Prepare(deleteQueueEDUSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUStmt, err = s.db.Prepare(selectQueueEDUSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUReferenceJSONCountStmt, err = s.db.Prepare(selectQueueEDUReferenceJSONCountSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUCountStmt, err = s.db.Prepare(selectQueueEDUCountSQL); err != nil {
-		return
-	}
-	if s.selectQueueEDUServerNamesStmt, err = s.db.Prepare(selectQueueServerNamesSQL); err != nil {
-		return
-	}
-	return
+
+	return s, nil
+}
+
+func (s *queueEDUsStatements) Prepare() error {
+	return sqlutil.StatementList{
+		{&s.insertQueueEDUStmt, insertQueueEDUSQL},
+		{&s.deleteQueueEDUStmt, deleteQueueEDUSQL},
+		{&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(
@@ -110,6 +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(
@@ -117,6 +137,7 @@ func (s *queueEDUsStatements) InsertQueueEDU(
 		eduType,    // the EDU type
 		serverName, // destination server name
 		nid,        // JSON blob NID
+		expiresAt,  // timestamp of expiry
 	)
 	return err
 }
@@ -150,7 +171,7 @@ func (s *queueEDUsStatements) SelectQueueEDUs(
 		}
 		result = append(result, nid)
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *queueEDUsStatements) SelectQueueEDUReferenceJSONCount(
@@ -200,3 +221,33 @@ 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
+}

federationapi/storage/postgres/storage.go

@@ -91,6 +91,9 @@ 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,

federationapi/storage/shared/storage_edus.go

@@ -20,10 +20,21 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"time"
 
 	"github.com/matrix-org/gomatrixserverlib"
 )
 
+// defaultExpiry for EDUs if not listed below
+var defaultExpiry = time.Hour * 24
+
+// defaultExpireEDUTypes contains EDUs which can/should be expired after a given time
+// if the target server isn't reachable for some reason.
+var defaultExpireEDUTypes = map[string]time.Duration{
+	gomatrixserverlib.MTyping:   time.Minute,
+	gomatrixserverlib.MPresence: time.Minute * 10,
+}
+
 // AssociateEDUWithDestination creates an association that the
 // destination queues will use to determine which JSON blobs to send
 // to which servers.
@@ -32,7 +43,21 @@ func (d *Database) AssociateEDUWithDestination(
 	serverName gomatrixserverlib.ServerName,
 	receipt *Receipt,
 	eduType string,
+	expireEDUTypes map[string]time.Duration,
 ) error {
+	if expireEDUTypes == nil {
+		expireEDUTypes = defaultExpireEDUTypes
+	}
+	expiresAt := gomatrixserverlib.AsTimestamp(time.Now().Add(defaultExpiry))
+	if duration, ok := expireEDUTypes[eduType]; ok {
+		// Keep EDUs for at least x minutes before deleting them
+		expiresAt = gomatrixserverlib.AsTimestamp(time.Now().Add(duration))
+	}
+	// We forcibly set m.direct_to_device events to 0, as we always want them
+	// to be delivered. (required for E2EE)
+	if eduType == gomatrixserverlib.MDirectToDevice {
+		expiresAt = 0
+	}
 	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
 		if err := d.FederationQueueEDUs.InsertQueueEDU(
 			ctx,         // context
@@ -40,6 +65,7 @@ func (d *Database) AssociateEDUWithDestination(
 			eduType,     // EDU type for coalescing
 			serverName,  // destination server name
 			receipt.nid, // NID from the federationapi_queue_json table
+			expiresAt,   // The timestamp this EDU will expire
 		); err != nil {
 			return fmt.Errorf("InsertQueueEDU: %w", err)
 		}
@@ -150,3 +176,26 @@ func (d *Database) GetPendingEDUServerNames(
 ) ([]gomatrixserverlib.ServerName, error) {
 	return d.FederationQueueEDUs.SelectQueueEDUServerNames(ctx, nil)
 }
+
+// DeleteExpiredEDUs deletes expired EDUs
+func (d *Database) DeleteExpiredEDUs(ctx context.Context) error {
+	return d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
+		expiredBefore := gomatrixserverlib.AsTimestamp(time.Now())
+		jsonNIDs, err := d.FederationQueueEDUs.SelectExpiredEDUs(ctx, txn, expiredBefore)
+		if err != nil {
+			return err
+		}
+		if len(jsonNIDs) == 0 {
+			return nil
+		}
+		for i := range jsonNIDs {
+			d.Cache.EvictFederationQueuedEDU(jsonNIDs[i])
+		}
+
+		if err = d.FederationQueueJSON.DeleteQueueJSON(ctx, txn, jsonNIDs); err != nil {
+			return err
+		}
+
+		return d.FederationQueueEDUs.DeleteExpiredEDUs(ctx, txn, expiredBefore)
+	})
+}

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
+}

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
+	// 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
+		return s, err
 	}
-	if s.insertQueueEDUStmt, err = db.Prepare(insertQueueEDUSQL); 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
 	}
-	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
-	}
-	if s.selectQueueEDUServerNamesStmt, err = db.Prepare(selectQueueServerNamesSQL); err != nil {
-		return
-	}
-	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
+}

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,

federationapi/storage/storage_test.go

@@ -0,0 +1,81 @@
+package storage_test
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/stretchr/testify/assert"
+
+	"github.com/matrix-org/dendrite/federationapi/storage"
+	"github.com/matrix-org/dendrite/setup/config"
+	"github.com/matrix-org/dendrite/test"
+	"github.com/matrix-org/dendrite/test/testrig"
+)
+
+func mustCreateFederationDatabase(t *testing.T, dbType test.DBType) (storage.Database, func()) {
+	b, baseClose := testrig.CreateBaseDendrite(t, dbType)
+	connStr, dbClose := test.PrepareDBConnectionString(t, dbType)
+	db, err := storage.NewDatabase(b, &config.DatabaseOptions{
+		ConnectionString: config.DataSource(connStr),
+	}, b.Caches, b.Cfg.Global.ServerName)
+	if err != nil {
+		t.Fatalf("NewDatabase returned %s", err)
+	}
+	return db, func() {
+		dbClose()
+		baseClose()
+	}
+}
+
+func TestExpireEDUs(t *testing.T) {
+	var expireEDUTypes = map[string]time.Duration{
+		gomatrixserverlib.MReceipt: time.Millisecond,
+	}
+
+	ctx := context.Background()
+	test.WithAllDatabases(t, func(t *testing.T, dbType test.DBType) {
+		db, close := mustCreateFederationDatabase(t, dbType)
+		defer close()
+		// insert some data
+		for i := 0; i < 100; i++ {
+			receipt, err := db.StoreJSON(ctx, "{}")
+			assert.NoError(t, err)
+
+			err = db.AssociateEDUWithDestination(ctx, "localhost", receipt, gomatrixserverlib.MReceipt, expireEDUTypes)
+			assert.NoError(t, err)
+		}
+		// add data without expiry
+		receipt, err := db.StoreJSON(ctx, "{}")
+		assert.NoError(t, err)
+
+		// m.read_marker gets the default expiry of 24h, so won't be deleted further down in this test
+		err = db.AssociateEDUWithDestination(ctx, "localhost", receipt, "m.read_marker", expireEDUTypes)
+		assert.NoError(t, err)
+
+		// Delete expired EDUs
+		err = db.DeleteExpiredEDUs(ctx)
+		assert.NoError(t, err)
+
+		// verify the data is gone
+		data, err := db.GetPendingEDUs(ctx, "localhost", 100)
+		assert.NoError(t, err)
+		assert.Equal(t, 1, len(data))
+
+		// check that m.direct_to_device is never expired
+		receipt, err = db.StoreJSON(ctx, "{}")
+		assert.NoError(t, err)
+
+		err = db.AssociateEDUWithDestination(ctx, "localhost", receipt, gomatrixserverlib.MDirectToDevice, expireEDUTypes)
+		assert.NoError(t, err)
+
+		err = db.DeleteExpiredEDUs(ctx)
+		assert.NoError(t, err)
+
+		// We should get two EDUs, the m.read_marker and the m.direct_to_device
+		data, err = db.GetPendingEDUs(ctx, "localhost", 100)
+		assert.NoError(t, err)
+		assert.Equal(t, 2, len(data))
+	})
+}

federationapi/storage/tables/interface.go

@@ -34,12 +34,15 @@ type FederationQueuePDUs interface {
 }
 
 type FederationQueueEDUs interface {
-	InsertQueueEDU(ctx context.Context, txn *sql.Tx, eduType string, serverName gomatrixserverlib.ServerName, nid int64) error
+	InsertQueueEDU(ctx context.Context, txn *sql.Tx, eduType string, serverName gomatrixserverlib.ServerName, nid int64, expiresAt gomatrixserverlib.Timestamp) error
 	DeleteQueueEDUs(ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName, jsonNIDs []int64) error
 	SelectQueueEDUs(ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName, limit int) ([]int64, error)
 	SelectQueueEDUReferenceJSONCount(ctx context.Context, txn *sql.Tx, jsonNID int64) (int64, error)
 	SelectQueueEDUCount(ctx context.Context, txn *sql.Tx, serverName gomatrixserverlib.ServerName) (int64, error)
 	SelectQueueEDUServerNames(ctx context.Context, txn *sql.Tx) ([]gomatrixserverlib.ServerName, error)
+	SelectExpiredEDUs(ctx context.Context, txn *sql.Tx, expiredBefore gomatrixserverlib.Timestamp) ([]int64, error)
+	DeleteExpiredEDUs(ctx context.Context, txn *sql.Tx, expiredBefore gomatrixserverlib.Timestamp) error
+	Prepare() error
 }
 
 type FederationQueueJSON interface {