Merge branch 'main' into contributing-links

appservice/appservice_test.go

@@ -14,6 +14,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/stretchr/testify/assert"
 
 	"github.com/matrix-org/dendrite/appservice"
@@ -32,6 +33,10 @@ import (
 	"github.com/matrix-org/dendrite/test/testrig"
 )
 
+var testIsBlacklistedOrBackingOff = func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+	return &statistics.ServerStatistics{}, nil
+}
+
 func TestAppserviceInternalAPI(t *testing.T) {
 
 	// Set expected results
@@ -144,7 +149,7 @@ func TestAppserviceInternalAPI(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(ctx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(ctx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		usrAPI := userapi.NewInternalAPI(ctx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		usrAPI := userapi.NewInternalAPI(ctx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		asAPI := appservice.NewInternalAPI(ctx, cfg, &natsInstance, usrAPI, rsAPI)
 
 		runCases(t, asAPI)
@@ -239,7 +244,7 @@ func TestAppserviceInternalAPI_UnixSocket_Simple(t *testing.T) {
 	cm := sqlutil.NewConnectionManager(ctx, cfg.Global.DatabaseOptions)
 	rsAPI := roomserver.NewInternalAPI(ctx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 	rsAPI.SetFederationAPI(nil, nil)
-	usrAPI := userapi.NewInternalAPI(ctx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+	usrAPI := userapi.NewInternalAPI(ctx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 	asAPI := appservice.NewInternalAPI(ctx, cfg, &natsInstance, usrAPI, rsAPI)
 
 	t.Run("UserIDExists", func(t *testing.T) {
@@ -378,7 +383,7 @@ func TestRoomserverConsumerOneInvite(t *testing.T) {
 		// Create required internal APIs
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		usrAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics)
+		usrAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		// start the consumer
 		appservice.NewInternalAPI(processCtx, cfg, natsInstance, usrAPI, rsAPI)
 

build/dendritejs-pinecone/main.go

@@ -191,13 +191,13 @@ func startup() {
 	serverKeyAPI := &signing.YggdrasilKeys{}
 	keyRing := serverKeyAPI.KeyRing()
 
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics)
+	fedSenderAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, federation, rsAPI, caches, keyRing, true)
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics, fedSenderAPI.IsBlacklistedOrBackingOff)
 
 	asQuery := appservice.NewInternalAPI(
 		processCtx, cfg, &natsInstance, userAPI, rsAPI,
 	)
 	rsAPI.SetAppserviceAPI(asQuery)
-	fedSenderAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, federation, rsAPI, caches, keyRing, true)
 	rsAPI.SetFederationAPI(fedSenderAPI, keyRing)
 
 	monolith := setup.Monolith{

build/gobind-yggdrasil/monolith.go

@@ -216,7 +216,7 @@ func (m *DendriteMonolith) Start() {
 		processCtx, cfg, cm, &natsInstance, federation, rsAPI, caches, keyRing, true,
 	)
 
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics)
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics, fsAPI.IsBlacklistedOrBackingOff)
 
 	asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
 	rsAPI.SetAppserviceAPI(asAPI)

clientapi/admin_test.go

@@ -45,7 +45,7 @@ func TestAdminCreateToken(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 		accessTokens := map[*test.User]userDevice{
 			aliceAdmin: {},
@@ -196,7 +196,7 @@ func TestAdminListRegistrationTokens(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 		accessTokens := map[*test.User]userDevice{
 			aliceAdmin: {},
@@ -314,7 +314,7 @@ func TestAdminGetRegistrationToken(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 		accessTokens := map[*test.User]userDevice{
 			aliceAdmin: {},
@@ -415,7 +415,7 @@ func TestAdminDeleteRegistrationToken(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 		accessTokens := map[*test.User]userDevice{
 			aliceAdmin: {},
@@ -509,7 +509,7 @@ func TestAdminUpdateRegistrationToken(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 		accessTokens := map[*test.User]userDevice{
 			aliceAdmin: {},
@@ -693,7 +693,7 @@ func TestAdminResetPassword(t *testing.T) {
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
 		// Needed for changing the password/login
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		// We mostly need the userAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 
@@ -791,7 +791,7 @@ func TestPurgeRoom(t *testing.T) {
 		fsAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, rsAPI, caches, nil, true)
 		rsAPI.SetFederationAPI(fsAPI, nil)
 
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		syncapi.AddPublicRoutes(processCtx, routers, cfg, cm, &natsInstance, userAPI, rsAPI, caches, caching.DisableMetrics)
 
 		// Create the room
@@ -863,7 +863,7 @@ func TestAdminEvacuateRoom(t *testing.T) {
 		fsAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, rsAPI, caches, nil, true)
 		rsAPI.SetFederationAPI(fsAPI, nil)
 
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// Create the room
 		if err := api.SendEvents(ctx, rsAPI, api.KindNew, room.Events(), "test", "test", api.DoNotSendToOtherServers, nil, false); err != nil {
@@ -964,7 +964,7 @@ func TestAdminEvacuateUser(t *testing.T) {
 		fsAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, basepkg.CreateFederationClient(cfg, nil), rsAPI, caches, nil, true)
 		rsAPI.SetFederationAPI(fsAPI, nil)
 
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// Create the room
 		if err := api.SendEvents(ctx, rsAPI, api.KindNew, room.Events(), "test", "test", api.DoNotSendToOtherServers, nil, false); err != nil {
@@ -1055,7 +1055,7 @@ func TestAdminMarkAsStale(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)

clientapi/clientapi_test.go

@@ -17,6 +17,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/routing"
 	"github.com/matrix-org/dendrite/clientapi/threepid"
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/httputil"
 	"github.com/matrix-org/dendrite/internal/pushrules"
@@ -49,6 +50,10 @@ type userDevice struct {
 	password    string
 }
 
+var testIsBlacklistedOrBackingOff = func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+	return &statistics.ServerStatistics{}, nil
+}
+
 func TestGetPutDevices(t *testing.T) {
 	alice := test.NewUser(t)
 	bob := test.NewUser(t)
@@ -121,7 +126,7 @@ func TestGetPutDevices(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -170,7 +175,7 @@ func TestDeleteDevice(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI/ for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -275,7 +280,7 @@ func TestDeleteDevices(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI/ for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -442,7 +447,7 @@ func TestSetDisplayname(t *testing.T) {
 
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		asPI := appservice.NewInternalAPI(processCtx, cfg, natsInstance, userAPI, rsAPI)
 
 		AddPublicRoutes(processCtx, routers, cfg, natsInstance, base.CreateFederationClient(cfg, nil), rsAPI, asPI, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -554,7 +559,7 @@ func TestSetAvatarURL(t *testing.T) {
 
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		asPI := appservice.NewInternalAPI(processCtx, cfg, natsInstance, userAPI, rsAPI)
 
 		AddPublicRoutes(processCtx, routers, cfg, natsInstance, base.CreateFederationClient(cfg, nil), rsAPI, asPI, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -632,7 +637,7 @@ func TestTyping(t *testing.T) {
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
 		// Needed to create accounts
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		// We mostly need the rsAPI/userAPI for this test, so nil for other APIs etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 
@@ -716,7 +721,7 @@ func TestMembership(t *testing.T) {
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
 		// Needed to create accounts
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		rsAPI.SetUserAPI(userAPI)
 		// We mostly need the rsAPI/userAPI for this test, so nil for other APIs etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -955,7 +960,7 @@ func TestCapabilities(t *testing.T) {
 		// Needed to create accounts
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		// We mostly need the rsAPI/userAPI for this test, so nil for other APIs etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 
@@ -1002,7 +1007,7 @@ func TestTurnserver(t *testing.T) {
 	// Needed to create accounts
 	rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, caching.DisableMetrics)
 	rsAPI.SetFederationAPI(nil, nil)
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 	//rsAPI.SetUserAPI(userAPI)
 	// We mostly need the rsAPI/userAPI for this test, so nil for other APIs etc.
 	AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -1100,7 +1105,7 @@ func Test3PID(t *testing.T) {
 		// Needed to create accounts
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		// We mostly need the rsAPI/userAPI for this test, so nil for other APIs etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
 
@@ -1276,7 +1281,7 @@ func TestPushRules(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -1663,7 +1668,7 @@ func TestKeys(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)
@@ -2125,7 +2130,7 @@ func TestKeyBackup(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the rsAPI for this test, so nil for other APIs/caches etc.
 		AddPublicRoutes(processCtx, routers, cfg, &natsInstance, nil, rsAPI, nil, nil, nil, userAPI, nil, nil, caching.DisableMetrics)

clientapi/routing/joinroom_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/setup/jetstream"
@@ -21,6 +22,10 @@ import (
 	uapi "github.com/matrix-org/dendrite/userapi/api"
 )
 
+var testIsBlacklistedOrBackingOff = func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+	return &statistics.ServerStatistics{}, nil
+}
+
 func TestJoinRoomByIDOrAlias(t *testing.T) {
 	alice := test.NewUser(t)
 	bob := test.NewUser(t)
@@ -36,7 +41,7 @@ func TestJoinRoomByIDOrAlias(t *testing.T) {
 		natsInstance := jetstream.NATSInstance{}
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil) // creates the rs.Inputer etc
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
 
 		// Create the users in the userapi

clientapi/routing/login_test.go

@@ -49,7 +49,7 @@ func TestLogin(t *testing.T) {
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
 		// Needed for /login
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		// We mostly need the userAPI for this test, so nil for other APIs/caches etc.
 		Setup(routers, cfg, nil, nil, userAPI, nil, nil, nil, nil, nil, nil, nil, caching.DisableMetrics)

clientapi/routing/register_test.go

@@ -416,7 +416,7 @@ func Test_register(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		for _, tc := range testCases {
 			t.Run(tc.name, func(t *testing.T) {
@@ -596,7 +596,7 @@ func TestRegisterUserWithDisplayName(t *testing.T) {
 		cm := sqlutil.NewConnectionManager(processCtx, cfg.Global.DatabaseOptions)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		deviceName, deviceID := "deviceName", "deviceID"
 		expectedDisplayName := "DisplayName"
 		response := completeRegistration(
@@ -637,7 +637,7 @@ func TestRegisterAdminUsingSharedSecret(t *testing.T) {
 		caches := caching.NewRistrettoCache(128*1024*1024, time.Hour, caching.DisableMetrics)
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 
 		expectedDisplayName := "rabbit"
 		jsonStr := []byte(`{"admin":true,"mac":"24dca3bba410e43fe64b9b5c28306693bf3baa9f","nonce":"759f047f312b99ff428b21d581256f8592b8976e58bc1b543972dc6147e529a79657605b52d7becd160ff5137f3de11975684319187e06901955f79e5a6c5a79","password":"wonderland","username":"alice","displayname":"rabbit"}`)

cmd/dendrite-demo-pinecone/monolith/monolith.go

@@ -145,7 +145,7 @@ func (p *P2PMonolith) SetupDendrite(
 	)
 	rsAPI.SetFederationAPI(fsAPI, keyRing)
 
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, enableMetrics)
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, enableMetrics, fsAPI.IsBlacklistedOrBackingOff)
 
 	asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
 

cmd/dendrite-demo-yggdrasil/main.go

@@ -213,14 +213,15 @@ func main() {
 	natsInstance := jetstream.NATSInstance{}
 	rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.EnableMetrics)
 
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics)
-
-	asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
-	rsAPI.SetAppserviceAPI(asAPI)
 	fsAPI := federationapi.NewInternalAPI(
 		processCtx, cfg, cm, &natsInstance, federation, rsAPI, caches, keyRing, true,
 	)
 
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federation, caching.EnableMetrics, fsAPI.IsBlacklistedOrBackingOff)
+
+	asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
+	rsAPI.SetAppserviceAPI(asAPI)
+
 	rsAPI.SetFederationAPI(fsAPI, keyRing)
 
 	monolith := setup.Monolith{

cmd/dendrite/main.go

@@ -162,7 +162,7 @@ func main() {
 	// dependency. Other components also need updating after their dependencies are up.
 	rsAPI.SetFederationAPI(fsAPI, keyRing)
 
-	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federationClient, caching.EnableMetrics)
+	userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, federationClient, caching.EnableMetrics, fsAPI.IsBlacklistedOrBackingOff)
 	asAPI := appservice.NewInternalAPI(processCtx, cfg, &natsInstance, userAPI, rsAPI)
 
 	rsAPI.SetAppserviceAPI(asAPI)

federationapi/federationapi.go

@@ -24,7 +24,6 @@ import (
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/federationapi/api"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/federationapi/consumers"
 	"github.com/matrix-org/dendrite/federationapi/internal"
@@ -102,7 +101,7 @@ func NewInternalAPI(
 	caches *caching.Caches,
 	keyRing *gomatrixserverlib.KeyRing,
 	resetBlacklist bool,
-) api.FederationInternalAPI {
+) *internal.FederationInternalAPI {
 	cfg := &dendriteCfg.FederationAPI
 
 	federationDB, err := storage.NewDatabase(processContext.Context(), cm, &cfg.Database, caches, dendriteCfg.Global.IsLocalServerName)

federationapi/internal/api.go

@@ -112,7 +112,7 @@ func NewFederationInternalAPI(
 	}
 }
 
-func (a *FederationInternalAPI) isBlacklistedOrBackingOff(s spec.ServerName) (*statistics.ServerStatistics, error) {
+func (a *FederationInternalAPI) IsBlacklistedOrBackingOff(s spec.ServerName) (*statistics.ServerStatistics, error) {
 	stats := a.statistics.ForServer(s)
 	if stats.Blacklisted() {
 		return stats, &api.FederationClientError{
@@ -151,7 +151,7 @@ func failBlacklistableError(err error, stats *statistics.ServerStatistics) (unti
 func (a *FederationInternalAPI) doRequestIfNotBackingOffOrBlacklisted(
 	s spec.ServerName, request func() (interface{}, error),
 ) (interface{}, error) {
-	stats, err := a.isBlacklistedOrBackingOff(s)
+	stats, err := a.IsBlacklistedOrBackingOff(s)
 	if err != nil {
 		return nil, err
 	}

federationapi/routing/profile_test.go

@@ -26,7 +26,6 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/cmd/dendrite-demo-yggdrasil/signing"
 	fedAPI "github.com/matrix-org/dendrite/federationapi"
-	fedInternal "github.com/matrix-org/dendrite/federationapi/internal"
 	"github.com/matrix-org/dendrite/federationapi/routing"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -67,11 +66,8 @@ func TestHandleQueryProfile(t *testing.T) {
 		keyRing := serverKeyAPI.KeyRing()
 		fedapi := fedAPI.NewInternalAPI(processCtx, cfg, cm, &natsInstance, &fedClient, nil, nil, keyRing, true)
 		userapi := fakeUserAPI{}
-		r, ok := fedapi.(*fedInternal.FederationInternalAPI)
+
-		if !ok {
+		routing.Setup(routers, cfg, nil, fedapi, keyRing, &fedClient, &userapi, &cfg.MSCs, nil, caching.DisableMetrics)
-			panic("This is a programming error.")
-		}
-		routing.Setup(routers, cfg, nil, r, keyRing, &fedClient, &userapi, &cfg.MSCs, nil, caching.DisableMetrics)
 
 		handler := fedMux.Get(routing.QueryProfileRouteName).GetHandler().ServeHTTP
 		_, sk, _ := ed25519.GenerateKey(nil)

federationapi/routing/query_test.go

@@ -25,7 +25,6 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/matrix-org/dendrite/cmd/dendrite-demo-yggdrasil/signing"
 	fedAPI "github.com/matrix-org/dendrite/federationapi"
-	fedInternal "github.com/matrix-org/dendrite/federationapi/internal"
 	"github.com/matrix-org/dendrite/federationapi/routing"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -65,11 +64,8 @@ func TestHandleQueryDirectory(t *testing.T) {
 		keyRing := serverKeyAPI.KeyRing()
 		fedapi := fedAPI.NewInternalAPI(processCtx, cfg, cm, &natsInstance, &fedClient, nil, nil, keyRing, true)
 		userapi := fakeUserAPI{}
-		r, ok := fedapi.(*fedInternal.FederationInternalAPI)
+
-		if !ok {
+		routing.Setup(routers, cfg, nil, fedapi, keyRing, &fedClient, &userapi, &cfg.MSCs, nil, caching.DisableMetrics)
-			panic("This is a programming error.")
-		}
-		routing.Setup(routers, cfg, nil, r, keyRing, &fedClient, &userapi, &cfg.MSCs, nil, caching.DisableMetrics)
 
 		handler := fedMux.Get(routing.QueryDirectoryRouteName).GetHandler().ServeHTTP
 		_, sk, _ := ed25519.GenerateKey(nil)

federationapi/routing/send_test.go

@@ -23,7 +23,6 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/matrix-org/dendrite/cmd/dendrite-demo-yggdrasil/signing"
 	fedAPI "github.com/matrix-org/dendrite/federationapi"
-	fedInternal "github.com/matrix-org/dendrite/federationapi/internal"
 	"github.com/matrix-org/dendrite/federationapi/routing"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -62,11 +61,8 @@ func TestHandleSend(t *testing.T) {
 		fedapi := fedAPI.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, nil, nil, nil, true)
 		serverKeyAPI := &signing.YggdrasilKeys{}
 		keyRing := serverKeyAPI.KeyRing()
-		r, ok := fedapi.(*fedInternal.FederationInternalAPI)
+
-		if !ok {
+		routing.Setup(routers, cfg, nil, fedapi, keyRing, nil, nil, &cfg.MSCs, nil, caching.DisableMetrics)
-			panic("This is a programming error.")
-		}
-		routing.Setup(routers, cfg, nil, r, keyRing, nil, nil, &cfg.MSCs, nil, caching.DisableMetrics)
 
 		handler := fedMux.Get(routing.SendRouteName).GetHandler().ServeHTTP
 		_, sk, _ := ed25519.GenerateKey(nil)

federationapi/storage/postgres/notary_server_keys_metadata_table.go

@@ -151,7 +151,7 @@ func (s *notaryServerKeysMetadataStatements) SelectKeys(ctx context.Context, txn
 		}
 		results = append(results, sk)
 	}
-	return results, nil
+	return results, rows.Err()
 }
 
 func (s *notaryServerKeysMetadataStatements) DeleteOldJSONResponses(ctx context.Context, txn *sql.Tx) error {

federationapi/storage/postgres/queue_json_table.go

@@ -109,5 +109,5 @@ func (s *queueJSONStatements) SelectQueueJSON(
 		}
 		blobs[nid] = blob
 	}
-	return blobs, err
+	return blobs, rows.Err()
 }

federationapi/storage/postgres/relay_servers_table.go

@@ -110,7 +110,7 @@ func (s *relayServersStatements) SelectRelayServers(
 		}
 		result = append(result, spec.ServerName(relayServer))
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *relayServersStatements) DeleteRelayServers(

federationapi/storage/sqlite3/joined_hosts_table.go

@@ -216,5 +216,5 @@ func joinedHostsFromStmt(
 		})
 	}
 
-	return result, nil
+	return result, rows.Err()
 }

federationapi/storage/sqlite3/notary_server_keys_metadata_table.go

@@ -154,7 +154,7 @@ func (s *notaryServerKeysMetadataStatements) SelectKeys(ctx context.Context, txn
 		}
 		results = append(results, sk)
 	}
-	return results, nil
+	return results, rows.Err()
 }
 
 func (s *notaryServerKeysMetadataStatements) DeleteOldJSONResponses(ctx context.Context, txn *sql.Tx) error {

federationapi/storage/sqlite3/queue_json_table.go

@@ -135,5 +135,5 @@ func (s *queueJSONStatements) SelectQueueJSON(
 		}
 		blobs[nid] = blob
 	}
-	return blobs, err
+	return blobs, rows.Err()
 }

federationapi/storage/sqlite3/relay_servers_table.go

@@ -109,7 +109,7 @@ func (s *relayServersStatements) SelectRelayServers(
 		}
 		result = append(result, spec.ServerName(relayServer))
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *relayServersStatements) DeleteRelayServers(

relayapi/storage/postgres/relay_queue_json_table.go

@@ -109,5 +109,5 @@ func (s *relayQueueJSONStatements) SelectQueueJSON(
 		}
 		blobs[nid] = blob
 	}
-	return blobs, err
+	return blobs, rows.Err()
 }

relayapi/storage/sqlite3/relay_queue_json_table.go

@@ -133,5 +133,5 @@ func (s *relayQueueJSONStatements) SelectQueueJSON(
 		}
 		blobs[nid] = blob
 	}
-	return blobs, err
+	return blobs, rows.Err()
 }

roomserver/internal/query/query_room_hierarchy.go

@@ -17,6 +17,7 @@ package query
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"sort"
 
@@ -56,6 +57,12 @@ func (querier *Queryer) QueryNextRoomHierarchyPage(ctx context.Context, walker r
 			break
 		}
 
+		// If the context is canceled, we might still have discovered rooms
+		// return them to the client and let the client know there _may_ be more rooms.
+		if errors.Is(ctx.Err(), context.Canceled) {
+			break
+		}
+
 		// pop the stack
 		queuedRoom := unvisited[len(unvisited)-1]
 		unvisited = unvisited[:len(unvisited)-1]
@@ -112,6 +119,11 @@ func (querier *Queryer) QueryNextRoomHierarchyPage(ctx context.Context, walker r
 
 			pubRoom := publicRoomsChunk(ctx, querier, queuedRoom.RoomID)
 
+			if pubRoom == nil {
+				util.GetLogger(ctx).WithField("room_id", queuedRoom.RoomID).Debug("unable to get publicRoomsChunk")
+				continue
+			}
+
 			discoveredRooms = append(discoveredRooms, fclient.RoomHierarchyRoom{
 				PublicRoom:    *pubRoom,
 				RoomType:      roomType,

roomserver/roomserver_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -34,6 +35,10 @@ import (
 	"github.com/matrix-org/dendrite/test/testrig"
 )
 
+var testIsBlacklistedOrBackingOff = func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+	return &statistics.ServerStatistics{}, nil
+}
+
 type FakeQuerier struct {
 	api.QuerySenderIDAPI
 }
@@ -58,7 +63,7 @@ func TestUsers(t *testing.T) {
 		})
 
 		t.Run("kick users", func(t *testing.T) {
-			usrAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+			usrAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 			rsAPI.SetUserAPI(usrAPI)
 			testKickUsers(t, rsAPI, usrAPI)
 		})
@@ -258,7 +263,7 @@ func TestPurgeRoom(t *testing.T) {
 		fsAPI := federationapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, nil, rsAPI, caches, nil, true)
 		rsAPI.SetFederationAPI(fsAPI, nil)
 
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, fsAPI.IsBlacklistedOrBackingOff)
 		syncapi.AddPublicRoutes(processCtx, routers, cfg, cm, &natsInstance, userAPI, rsAPI, caches, caching.DisableMetrics)
 
 		// Create the room
@@ -1050,7 +1055,7 @@ func TestUpgrade(t *testing.T) {
 
 		rsAPI := roomserver.NewInternalAPI(processCtx, cfg, cm, &natsInstance, caches, caching.DisableMetrics)
 		rsAPI.SetFederationAPI(nil, nil)
-		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics)
+		userAPI := userapi.NewInternalAPI(processCtx, cfg, cm, &natsInstance, rsAPI, nil, caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		rsAPI.SetUserAPI(userAPI)
 
 		for _, tc := range testCases {

roomserver/storage/postgres/events_table.go

@@ -249,6 +249,7 @@ func (s *eventStatements) BulkSelectSnapshotsFromEventIDs(
 	if err != nil {
 		return nil, err
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "BulkSelectSnapshotsFromEventIDs: rows.close() failed")
 
 	var eventID string
 	var stateNID types.StateSnapshotNID
@@ -563,7 +564,7 @@ func (s *eventStatements) SelectRoomNIDsForEventNIDs(
 		}
 		result[eventNID] = roomNID
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func eventNIDsAsArray(eventNIDs []types.EventNID) pq.Int64Array {

roomserver/storage/postgres/membership_table.go

@@ -363,7 +363,7 @@ func (s *membershipStatements) SelectRoomsWithMembership(
 		}
 		roomNIDs = append(roomNIDs, roomNID)
 	}
-	return roomNIDs, nil
+	return roomNIDs, rows.Err()
 }
 
 func (s *membershipStatements) SelectJoinedUsersSetForRooms(

roomserver/storage/postgres/rooms_table.go

@@ -137,7 +137,7 @@ func (s *roomStatements) SelectRoomIDsWithEvents(ctx context.Context, txn *sql.T
 		}
 		roomIDs = append(roomIDs, roomID)
 	}
-	return roomIDs, nil
+	return roomIDs, rows.Err()
 }
 func (s *roomStatements) InsertRoomNID(
 	ctx context.Context, txn *sql.Tx,
@@ -255,7 +255,7 @@ func (s *roomStatements) SelectRoomVersionsForRoomNIDs(
 		}
 		result[roomNID] = roomVersion
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *roomStatements) BulkSelectRoomIDs(ctx context.Context, txn *sql.Tx, roomNIDs []types.RoomNID) ([]string, error) {
@@ -277,7 +277,7 @@ func (s *roomStatements) BulkSelectRoomIDs(ctx context.Context, txn *sql.Tx, roo
 		}
 		roomIDs = append(roomIDs, roomID)
 	}
-	return roomIDs, nil
+	return roomIDs, rows.Err()
 }
 
 func (s *roomStatements) BulkSelectRoomNIDs(ctx context.Context, txn *sql.Tx, roomIDs []string) ([]types.RoomNID, error) {
@@ -299,7 +299,7 @@ func (s *roomStatements) BulkSelectRoomNIDs(ctx context.Context, txn *sql.Tx, ro
 		}
 		roomNIDs = append(roomNIDs, roomNID)
 	}
-	return roomNIDs, nil
+	return roomNIDs, rows.Err()
 }
 
 func roomNIDsAsArray(roomNIDs []types.RoomNID) pq.Int64Array {

roomserver/storage/postgres/user_room_keys_table.go

@@ -162,6 +162,7 @@ func (s *userRoomKeysStatements) SelectAllPublicKeysForUser(ctx context.Context,
 	if errors.Is(err, sql.ErrNoRows) {
 		return nil, nil
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectAllPublicKeysForUser: failed to close rows")
 
 	resultMap := make(map[types.RoomNID]ed25519.PublicKey)
 
@@ -173,5 +174,5 @@ func (s *userRoomKeysStatements) SelectAllPublicKeysForUser(ctx context.Context,
 		}
 		resultMap[roomNID] = pubkey
 	}
-	return resultMap, err
+	return resultMap, rows.Err()
 }

roomserver/storage/sqlite3/event_json_table.go

@@ -109,5 +109,5 @@ func (s *eventJSONStatements) BulkSelectEventJSON(
 		}
 		result.EventNID = types.EventNID(eventNID)
 	}
-	return results[:i], nil
+	return results[:i], rows.Err()
 }

roomserver/storage/sqlite3/event_state_keys_table.go

@@ -136,7 +136,7 @@ func (s *eventStateKeyStatements) BulkSelectEventStateKeyNID(
 		}
 		result[stateKey] = types.EventStateKeyNID(stateKeyNID)
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *eventStateKeyStatements) BulkSelectEventStateKey(
@@ -167,5 +167,5 @@ func (s *eventStateKeyStatements) BulkSelectEventStateKey(
 		}
 		result[types.EventStateKeyNID(stateKeyNID)] = stateKey
 	}
-	return result, nil
+	return result, rows.Err()
 }

roomserver/storage/sqlite3/event_types_table.go

@@ -147,5 +147,5 @@ func (s *eventTypeStatements) BulkSelectEventTypeNID(
 		}
 		result[eventType] = types.EventTypeNID(eventTypeNID)
 	}
-	return result, nil
+	return result, rows.Err()
 }

roomserver/storage/sqlite3/events_table.go

@@ -310,6 +310,9 @@ func (s *eventStatements) BulkSelectStateEventByID(
 		}
 		results = append(results, result)
 	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
 	if !excludeRejected && i != len(eventIDs) {
 		// If there are fewer rows returned than IDs then we were asked to lookup event IDs we don't have.
 		// We don't know which ones were missing because we don't return the string IDs in the query.
@@ -377,7 +380,7 @@ func (s *eventStatements) BulkSelectStateEventByNID(
 			return nil, err
 		}
 	}
-	return results[:i], err
+	return results[:i], rows.Err()
 }
 
 // bulkSelectStateAtEventByID lookups the state at a list of events by event ID.
@@ -425,6 +428,9 @@ func (s *eventStatements) BulkSelectStateAtEventByID(
 			)
 		}
 	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
 	if i != len(eventIDs) {
 		return nil, types.MissingEventError(
 			fmt.Sprintf("storage: event IDs missing from the database (%d != %d)", i, len(eventIDs)),
@@ -507,6 +513,9 @@ func (s *eventStatements) BulkSelectStateAtEventAndReference(
 		result.BeforeStateSnapshotNID = types.StateSnapshotNID(stateSnapshotNID)
 		result.EventID = eventID
 	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
 	if i != len(eventNIDs) {
 		return nil, fmt.Errorf("storage: event NIDs missing from the database (%d != %d)", i, len(eventNIDs))
 	}
@@ -544,6 +553,9 @@ func (s *eventStatements) BulkSelectEventID(ctx context.Context, txn *sql.Tx, ev
 		}
 		results[types.EventNID(eventNID)] = eventID
 	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
 	if i != len(eventNIDs) {
 		return nil, fmt.Errorf("storage: event NIDs missing from the database (%d != %d)", i, len(eventNIDs))
 	}
@@ -602,7 +614,7 @@ func (s *eventStatements) bulkSelectEventNID(ctx context.Context, txn *sql.Tx, e
 			RoomNID:  types.RoomNID(roomNID),
 		}
 	}
-	return results, nil
+	return results, rows.Err()
 }
 
 func (s *eventStatements) SelectMaxEventDepth(ctx context.Context, txn *sql.Tx, eventNIDs []types.EventNID) (int64, error) {
@@ -652,7 +664,7 @@ func (s *eventStatements) SelectRoomNIDsForEventNIDs(
 		}
 		result[eventNID] = roomNID
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func eventNIDsAsArray(eventNIDs []types.EventNID) string {

roomserver/storage/sqlite3/invite_table.go

@@ -126,6 +126,9 @@ func (s *inviteStatements) UpdateInviteRetired(
 		}
 		eventIDs = append(eventIDs, inviteEventID)
 	}
+	if err = rows.Err(); err != nil {
+		return
+	}
 	// now retire the invites
 	stmt = sqlutil.TxStmt(txn, s.updateInviteRetiredStmt)
 	_, err = stmt.ExecContext(ctx, roomNID, targetUserNID)
@@ -157,5 +160,5 @@ func (s *inviteStatements) SelectInviteActiveForUserInRoom(
 		result = append(result, types.EventStateKeyNID(senderUserNID))
 		eventIDs = append(eventIDs, eventID)
 	}
-	return result, eventIDs, eventJSON, nil
+	return result, eventIDs, eventJSON, rows.Err()
 }

roomserver/storage/sqlite3/membership_table.go

@@ -250,6 +250,7 @@ func (s *membershipStatements) SelectMembershipsFromRoom(
 		}
 		eventNIDs = append(eventNIDs, eNID)
 	}
+	err = rows.Err()
 	return
 }
 
@@ -277,6 +278,7 @@ func (s *membershipStatements) SelectMembershipsFromRoomAndMembership(
 		}
 		eventNIDs = append(eventNIDs, eNID)
 	}
+	err = rows.Err()
 	return
 }
 
@@ -313,7 +315,7 @@ func (s *membershipStatements) SelectRoomsWithMembership(
 		}
 		roomNIDs = append(roomNIDs, roomNID)
 	}
-	return roomNIDs, nil
+	return roomNIDs, rows.Err()
 }
 
 func (s *membershipStatements) SelectJoinedUsersSetForRooms(ctx context.Context, txn *sql.Tx, roomNIDs []types.RoomNID, userNIDs []types.EventStateKeyNID, localOnly bool) (map[types.EventStateKeyNID]int, error) {

roomserver/storage/sqlite3/room_aliases_table.go

@@ -121,7 +121,7 @@ func (s *roomAliasesStatements) SelectAliasesFromRoomID(
 
 		aliases = append(aliases, alias)
 	}
-
+	err = rows.Err()
 	return
 }
 

roomserver/storage/sqlite3/rooms_table.go

@@ -128,7 +128,7 @@ func (s *roomStatements) SelectRoomIDsWithEvents(ctx context.Context, txn *sql.T
 		}
 		roomIDs = append(roomIDs, roomID)
 	}
-	return roomIDs, nil
+	return roomIDs, rows.Err()
 }
 
 func (s *roomStatements) SelectRoomInfo(ctx context.Context, txn *sql.Tx, roomID string) (*types.RoomInfo, error) {
@@ -265,7 +265,7 @@ func (s *roomStatements) SelectRoomVersionsForRoomNIDs(
 		}
 		result[roomNID] = roomVersion
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *roomStatements) BulkSelectRoomIDs(ctx context.Context, txn *sql.Tx, roomNIDs []types.RoomNID) ([]string, error) {
@@ -293,7 +293,7 @@ func (s *roomStatements) BulkSelectRoomIDs(ctx context.Context, txn *sql.Tx, roo
 		}
 		roomIDs = append(roomIDs, roomID)
 	}
-	return roomIDs, nil
+	return roomIDs, rows.Err()
 }
 
 func (s *roomStatements) BulkSelectRoomNIDs(ctx context.Context, txn *sql.Tx, roomIDs []string) ([]types.RoomNID, error) {
@@ -321,5 +321,5 @@ func (s *roomStatements) BulkSelectRoomNIDs(ctx context.Context, txn *sql.Tx, ro
 		}
 		roomNIDs = append(roomNIDs, roomNID)
 	}
-	return roomNIDs, nil
+	return roomNIDs, rows.Err()
 }

roomserver/storage/sqlite3/state_snapshot_table.go

@@ -133,13 +133,16 @@ func (s *stateSnapshotStatements) BulkSelectStateBlockNIDs(
 	var stateBlockNIDsJSON string
 	for ; rows.Next(); i++ {
 		result := &results[i]
-		if err := rows.Scan(&result.StateSnapshotNID, &stateBlockNIDsJSON); err != nil {
+		if err = rows.Scan(&result.StateSnapshotNID, &stateBlockNIDsJSON); err != nil {
 			return nil, err
 		}
-		if err := json.Unmarshal([]byte(stateBlockNIDsJSON), &result.StateBlockNIDs); err != nil {
+		if err = json.Unmarshal([]byte(stateBlockNIDsJSON), &result.StateBlockNIDs); err != nil {
 			return nil, err
 		}
 	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
 	if i != len(stateNIDs) {
 		return nil, types.MissingStateError(fmt.Sprintf("storage: state NIDs missing from the database (%d != %d)", i, len(stateNIDs)))
 	}

roomserver/storage/sqlite3/user_room_keys_table.go

@@ -177,6 +177,7 @@ func (s *userRoomKeysStatements) SelectAllPublicKeysForUser(ctx context.Context,
 	if errors.Is(err, sql.ErrNoRows) {
 		return nil, nil
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectAllPublicKeysForUser: failed to close rows")
 
 	resultMap := make(map[types.RoomNID]ed25519.PublicKey)
 
@@ -188,5 +189,5 @@ func (s *userRoomKeysStatements) SelectAllPublicKeysForUser(ctx context.Context,
 		}
 		resultMap[roomNID] = pubkey
 	}
-	return resultMap, err
+	return resultMap, rows.Err()
 }

setup/mscs/msc2836/storage.go

@@ -301,7 +301,7 @@ func (p *DB) ChildrenForParent(ctx context.Context, eventID, relType string, rec
 		}
 		children = append(children, evInfo)
 	}
-	return children, nil
+	return children, rows.Err()
 }
 
 func (p *DB) ParentForChild(ctx context.Context, eventID, relType string) (*eventInfo, error) {

syncapi/routing/getevent.go

@@ -44,7 +44,7 @@ func GetEvent(
 	rsAPI api.SyncRoomserverAPI,
 ) util.JSONResponse {
 	ctx := req.Context()
-	db, err := syncDB.NewDatabaseTransaction(ctx)
+	db, err := syncDB.NewDatabaseSnapshot(ctx)
 	logger := util.GetLogger(ctx).WithFields(logrus.Fields{
 		"event_id": eventID,
 		"room_id":  rawRoomID,
@@ -56,6 +56,7 @@ func GetEvent(
 			JSON: spec.InternalServerError{},
 		}
 	}
+	defer db.Rollback() // nolint: errcheck
 
 	roomID, err := spec.NewRoomID(rawRoomID)
 	if err != nil {

syncapi/storage/postgres/current_room_state_table.go

@@ -392,7 +392,7 @@ func currentRoomStateRowsToStreamEvents(rows *sql.Rows) ([]types.StreamEvent, er
 		})
 	}
 
-	return events, nil
+	return events, rows.Err()
 }
 
 func rowsToEvents(rows *sql.Rows) ([]*rstypes.HeaderedEvent, error) {

syncapi/storage/postgres/memberships_table.go

@@ -19,6 +19,7 @@ import (
 	"database/sql"
 	"fmt"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	rstypes "github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/syncapi/storage/tables"
@@ -160,6 +161,7 @@ func (s *membershipsStatements) SelectMemberships(
 	if err != nil {
 		return
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectMemberships: failed to close rows")
 	var (
 		eventID string
 	)

syncapi/storage/postgres/peeks_table.go

@@ -164,7 +164,7 @@ func (s *peekStatements) SelectPeekingDevices(
 		devices = append(devices, types.PeekingDevice{UserID: userID, DeviceID: deviceID})
 		result[roomID] = devices
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *peekStatements) SelectMaxPeekID(

syncapi/storage/postgres/presence_table.go

@@ -144,7 +144,7 @@ func (p *presenceStatements) GetPresenceForUsers(
 		presence.ClientFields.Presence = presence.Presence.String()
 		result = append(result, presence)
 	}
-	return result, err
+	return result, rows.Err()
 }
 
 func (p *presenceStatements) GetMaxPresenceID(ctx context.Context, txn *sql.Tx) (pos types.StreamPosition, err error) {

syncapi/storage/sqlite3/current_room_state_table.go

@@ -177,7 +177,7 @@ func (s *currentRoomStateStatements) SelectJoinedUsers(
 		users = append(users, userID)
 		result[roomID] = users
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 // SelectJoinedUsersInRoom returns a map of room ID to a list of joined user IDs for a given room.
@@ -236,7 +236,7 @@ func (s *currentRoomStateStatements) SelectRoomIDsWithMembership(
 		}
 		result = append(result, roomID)
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 // SelectRoomIDsWithAnyMembership returns a map of all memberships for the given user.
@@ -419,7 +419,7 @@ func currentRoomStateRowsToStreamEvents(rows *sql.Rows) ([]types.StreamEvent, er
 		})
 	}
 
-	return events, nil
+	return events, rows.Err()
 }
 
 func rowsToEvents(rows *sql.Rows) ([]*rstypes.HeaderedEvent, error) {

syncapi/storage/sqlite3/invites_table.go

@@ -176,7 +176,7 @@ func (s *inviteEventsStatements) SelectInviteEventsInRange(
 	if lastPos == 0 {
 		lastPos = r.To
 	}
-	return result, retired, lastPos, nil
+	return result, retired, lastPos, rows.Err()
 }
 
 func (s *inviteEventsStatements) SelectMaxInviteID(

syncapi/storage/sqlite3/memberships_table.go

@@ -19,6 +19,7 @@ import (
 	"database/sql"
 	"fmt"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	rstypes "github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/syncapi/storage/tables"
@@ -163,6 +164,7 @@ func (s *membershipsStatements) SelectMemberships(
 	if err != nil {
 		return
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectMemberships: failed to close rows")
 	var eventID string
 	for rows.Next() {
 		if err = rows.Scan(&eventID); err != nil {

syncapi/storage/sqlite3/output_room_events_table.go

@@ -274,7 +274,7 @@ func (s *outputRoomEventsStatements) SelectStateInRange(
 		}
 	}
 
-	return stateNeeded, eventIDToEvent, nil
+	return stateNeeded, eventIDToEvent, rows.Err()
 }
 
 // MaxID returns the ID of the last inserted event in this table. 'txn' is optional. If it is not supplied,
@@ -520,7 +520,7 @@ func rowsToStreamEvents(rows *sql.Rows) ([]types.StreamEvent, error) {
 			ExcludeFromSync: excludeFromSync,
 		})
 	}
-	return result, nil
+	return result, rows.Err()
 }
 func (s *outputRoomEventsStatements) SelectContextEvent(
 	ctx context.Context, txn *sql.Tx, roomID, eventID string,

syncapi/storage/sqlite3/output_room_events_topology_table.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"database/sql"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	rstypes "github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/syncapi/storage/tables"
@@ -137,6 +138,7 @@ func (s *outputRoomEventsTopologyStatements) SelectEventIDsInRange(
 	} else if err != nil {
 		return
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectEventIDsInRange: failed to close rows")
 
 	// Return the IDs.
 	var eventID string
@@ -155,7 +157,7 @@ func (s *outputRoomEventsTopologyStatements) SelectEventIDsInRange(
 		start = tokens[0]
 		end = tokens[len(tokens)-1]
 	}
-
+	err = rows.Err()
 	return
 }
 

syncapi/storage/sqlite3/peeks_table.go

@@ -184,7 +184,7 @@ func (s *peekStatements) SelectPeekingDevices(
 		devices = append(devices, types.PeekingDevice{UserID: userID, DeviceID: deviceID})
 		result[roomID] = devices
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *peekStatements) SelectMaxPeekID(

syncapi/storage/sqlite3/presence_table.go

@@ -169,7 +169,7 @@ func (p *presenceStatements) GetPresenceForUsers(
 		presence.ClientFields.Presence = presence.Presence.String()
 		result = append(result, presence)
 	}
-	return result, err
+	return result, rows.Err()
 }
 
 func (p *presenceStatements) GetMaxPresenceID(ctx context.Context, txn *sql.Tx) (pos types.StreamPosition, err error) {

userapi/internal/device_list_update.go

@@ -25,6 +25,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	rsapi "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
@@ -108,6 +109,8 @@ type DeviceListUpdater struct {
 	userIDToChan   map[string]chan bool
 	userIDToChanMu *sync.Mutex
 	rsAPI          rsapi.KeyserverRoomserverAPI
+
+	isBlacklistedOrBackingOffFn func(s spec.ServerName) (*statistics.ServerStatistics, error)
 }
 
 // DeviceListUpdaterDatabase is the subset of functionality from storage.Database required for the updater.
@@ -167,25 +170,28 @@ func NewDeviceListUpdater(
 	process *process.ProcessContext, db DeviceListUpdaterDatabase,
 	api DeviceListUpdaterAPI, producer KeyChangeProducer,
 	fedClient fedsenderapi.KeyserverFederationAPI, numWorkers int,
-	rsAPI rsapi.KeyserverRoomserverAPI, thisServer spec.ServerName,
+	rsAPI rsapi.KeyserverRoomserverAPI,
+	thisServer spec.ServerName,
 	enableMetrics bool,
+	isBlacklistedOrBackingOffFn func(s spec.ServerName) (*statistics.ServerStatistics, error),
 ) *DeviceListUpdater {
 	if enableMetrics {
 		prometheus.MustRegister(deviceListUpdaterBackpressure, deviceListUpdaterServersRetrying)
 	}
 	return &DeviceListUpdater{
-		process:        process,
+		process:                     process,
-		userIDToMutex:  make(map[string]*sync.Mutex),
+		userIDToMutex:               make(map[string]*sync.Mutex),
-		mu:             &sync.Mutex{},
+		mu:                          &sync.Mutex{},
-		db:             db,
+		db:                          db,
-		api:            api,
+		api:                         api,
-		producer:       producer,
+		producer:                    producer,
-		fedClient:      fedClient,
+		fedClient:                   fedClient,
-		thisServer:     thisServer,
+		thisServer:                  thisServer,
-		workerChans:    make([]chan spec.ServerName, numWorkers),
+		workerChans:                 make([]chan spec.ServerName, numWorkers),
-		userIDToChan:   make(map[string]chan bool),
+		userIDToChan:                make(map[string]chan bool),
-		userIDToChanMu: &sync.Mutex{},
+		userIDToChanMu:              &sync.Mutex{},
-		rsAPI:          rsAPI,
+		rsAPI:                       rsAPI,
+		isBlacklistedOrBackingOffFn: isBlacklistedOrBackingOffFn,
 	}
 }
 
@@ -362,13 +368,22 @@ func (u *DeviceListUpdater) notifyWorkers(userID string) {
 	if err != nil {
 		return
 	}
+	_, err = u.isBlacklistedOrBackingOffFn(remoteServer)
+	var federationClientError *fedsenderapi.FederationClientError
+	if errors.As(err, &federationClientError) {
+		if federationClientError.Blacklisted {
+			return
+		}
+	}
+
 	hash := fnv.New32a()
 	_, _ = hash.Write([]byte(remoteServer))
 	index := int(int64(hash.Sum32()) % int64(len(u.workerChans)))
 
 	ch := u.assignChannel(userID)
+	// Since workerChans are buffered, we only increment here and let the worker
+	// decrement it once it is done processing.
 	deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(index)}).Inc()
-	defer deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(index)}).Dec()
 	u.workerChans[index] <- remoteServer
 	select {
 	case <-ch:
@@ -405,24 +420,38 @@ func (u *DeviceListUpdater) worker(ch chan spec.ServerName, workerID int) {
 	go func() {
 		var serversToRetry []spec.ServerName
 		for {
-			serversToRetry = serversToRetry[:0] // reuse memory
+			// nuke serversToRetry by re-slicing it to be "empty".
-			time.Sleep(time.Second)
+			// The capacity of the slice is unchanged, which ensures we can reuse the memory.
+			serversToRetry = serversToRetry[:0]
+
+			deviceListUpdaterServersRetrying.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Set(float64(len(retries)))
+			time.Sleep(time.Second * 2)
+
+			// -2, so we have space for incoming device list updates over federation
+			maxServers := (cap(ch) - len(ch)) - 2
+			if maxServers <= 0 {
+				continue
+			}
+
 			retriesMu.Lock()
 			now := time.Now()
 			for srv, retryAt := range retries {
 				if now.After(retryAt) {
 					serversToRetry = append(serversToRetry, srv)
+					if maxServers == len(serversToRetry) {
+						break
+					}
 				}
 			}
+
 			for _, srv := range serversToRetry {
 				delete(retries, srv)
 			}
-			deviceListUpdaterServersRetrying.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Set(float64(len(retries)))
 			retriesMu.Unlock()
+
 			for _, srv := range serversToRetry {
 				deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Inc()
 				ch <- srv
-				deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Dec()
 			}
 		}
 	}()
@@ -430,8 +459,18 @@ func (u *DeviceListUpdater) worker(ch chan spec.ServerName, workerID int) {
 		retriesMu.Lock()
 		_, exists := retries[serverName]
 		retriesMu.Unlock()
-		if exists {
+
-			// Don't retry a server that we're already waiting for.
+		// If the serverName is coming from retries, maybe it was
+		// blacklisted in the meantime.
+		_, err := u.isBlacklistedOrBackingOffFn(serverName)
+		var federationClientError *fedsenderapi.FederationClientError
+		// unwrap errors and check for FederationClientError, if found, federationClientError will be not nil
+		errors.As(err, &federationClientError)
+		isBlacklisted := federationClientError != nil && federationClientError.Blacklisted
+
+		// Don't retry a server that we're already waiting for or is blacklisted by now.
+		if exists || isBlacklisted {
+			deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Dec()
 			continue
 		}
 		waitTime, shouldRetry := u.processServer(serverName)
@@ -442,6 +481,7 @@ func (u *DeviceListUpdater) worker(ch chan spec.ServerName, workerID int) {
 			}
 			retriesMu.Unlock()
 		}
+		deviceListUpdaterBackpressure.With(prometheus.Labels{"worker_id": strconv.Itoa(workerID)}).Dec()
 	}
 }
 

userapi/internal/device_list_update_test.go

@@ -27,6 +27,8 @@ import (
 	"testing"
 	"time"
 
+	api2 "github.com/matrix-org/dendrite/federationapi/api"
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -129,6 +131,10 @@ type mockDeviceListUpdaterAPI struct {
 func (d *mockDeviceListUpdaterAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) {
 }
 
+var testIsBlacklistedOrBackingOff = func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+	return &statistics.ServerStatistics{}, nil
+}
+
 type roundTripper struct {
 	fn func(*http.Request) (*http.Response, error)
 }
@@ -162,7 +168,7 @@ func TestUpdateHavePrevID(t *testing.T) {
 	}
 	ap := &mockDeviceListUpdaterAPI{}
 	producer := &mockKeyChangeProducer{}
-	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, nil, 1, nil, "localhost", caching.DisableMetrics)
+	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, nil, 1, nil, "localhost", caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 	event := gomatrixserverlib.DeviceListUpdateEvent{
 		DeviceDisplayName: "Foo Bar",
 		Deleted:           false,
@@ -234,7 +240,7 @@ func TestUpdateNoPrevID(t *testing.T) {
 			`)),
 		}, nil
 	})
-	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, fedClient, 2, nil, "example.test", caching.DisableMetrics)
+	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, fedClient, 2, nil, "example.test", caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 	if err := updater.Start(); err != nil {
 		t.Fatalf("failed to start updater: %s", err)
 	}
@@ -304,7 +310,7 @@ func TestDebounce(t *testing.T) {
 		close(incomingFedReq)
 		return <-fedCh, nil
 	})
-	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, fedClient, 1, nil, "localhost", caching.DisableMetrics)
+	updater := NewDeviceListUpdater(process.NewProcessContext(), db, ap, producer, fedClient, 1, nil, "localhost", caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 	if err := updater.Start(); err != nil {
 		t.Fatalf("failed to start updater: %s", err)
 	}
@@ -407,7 +413,7 @@ func TestDeviceListUpdater_CleanUp(t *testing.T) {
 
 		updater := NewDeviceListUpdater(processCtx, db, nil,
 			nil, nil,
-			0, rsAPI, "test", caching.DisableMetrics)
+			0, rsAPI, "test", caching.DisableMetrics, testIsBlacklistedOrBackingOff)
 		if err := updater.CleanUp(); err != nil {
 			t.Error(err)
 		}
@@ -475,3 +481,68 @@ func Test_dedupeStateList(t *testing.T) {
 		})
 	}
 }
+
+func TestDeviceListUpdaterIgnoreBlacklisted(t *testing.T) {
+	unreachableServer := spec.ServerName("notlocalhost")
+
+	updater := DeviceListUpdater{
+		workerChans: make([]chan spec.ServerName, 1),
+		isBlacklistedOrBackingOffFn: func(s spec.ServerName) (*statistics.ServerStatistics, error) {
+			switch s {
+			case unreachableServer:
+				return nil, &api2.FederationClientError{Blacklisted: true}
+			}
+			return nil, nil
+		},
+		mu:             &sync.Mutex{},
+		userIDToChanMu: &sync.Mutex{},
+		userIDToChan:   make(map[string]chan bool),
+		userIDToMutex:  make(map[string]*sync.Mutex),
+	}
+	workerCh := make(chan spec.ServerName)
+	defer close(workerCh)
+	updater.workerChans[0] = workerCh
+
+	// happy case
+	alice := "@alice:localhost"
+	aliceCh := updater.assignChannel(alice)
+	defer updater.clearChannel(alice)
+
+	// failing case
+	bob := "@bob:" + unreachableServer
+	bobCh := updater.assignChannel(string(bob))
+	defer updater.clearChannel(string(bob))
+
+	expectedServers := map[spec.ServerName]struct{}{
+		"localhost": {},
+	}
+	unexpectedServers := make(map[spec.ServerName]struct{})
+
+	go func() {
+		for serverName := range workerCh {
+			switch serverName {
+			case "localhost":
+				delete(expectedServers, serverName)
+				aliceCh <- true // unblock notifyWorkers
+			case unreachableServer: // this should not happen as it is "filtered" away by the blacklist
+				unexpectedServers[serverName] = struct{}{}
+				bobCh <- true
+			default:
+				unexpectedServers[serverName] = struct{}{}
+			}
+		}
+	}()
+
+	// alice is not blacklisted
+	updater.notifyWorkers(alice)
+	// bob is blacklisted
+	updater.notifyWorkers(string(bob))
+
+	for server := range expectedServers {
+		t.Errorf("Server still in expectedServers map: %s", server)
+	}
+
+	for server := range unexpectedServers {
+		t.Errorf("unexpected server in result: %s", server)
+	}
+}

userapi/storage/postgres/cross_signing_keys_table.go

@@ -77,7 +77,7 @@ func (s *crossSigningKeysStatements) SelectCrossSigningKeysForUser(
 	for rows.Next() {
 		var keyTypeInt int16
 		var keyData spec.Base64Bytes
-		if err := rows.Scan(&keyTypeInt, &keyData); err != nil {
+		if err = rows.Scan(&keyTypeInt, &keyData); err != nil {
 			return nil, err
 		}
 		keyType, ok := types.KeyTypeIntToPurpose[keyTypeInt]
@@ -86,6 +86,7 @@ func (s *crossSigningKeysStatements) SelectCrossSigningKeysForUser(
 		}
 		r[keyType] = keyData
 	}
+	err = rows.Err()
 	return
 }
 

userapi/storage/postgres/cross_signing_sigs_table.go

@@ -98,7 +98,7 @@ func (s *crossSigningSigsStatements) SelectCrossSigningSigsForTarget(
 		var userID string
 		var keyID gomatrixserverlib.KeyID
 		var signature spec.Base64Bytes
-		if err := rows.Scan(&userID, &keyID, &signature); err != nil {
+		if err = rows.Scan(&userID, &keyID, &signature); err != nil {
 			return nil, err
 		}
 		if _, ok := r[userID]; !ok {
@@ -106,6 +106,7 @@ func (s *crossSigningSigsStatements) SelectCrossSigningSigsForTarget(
 		}
 		r[userID][keyID] = signature
 	}
+	err = rows.Err()
 	return
 }
 

userapi/storage/postgres/key_backup_table.go

@@ -162,5 +162,5 @@ func unpackKeys(ctx context.Context, rows *sql.Rows) (map[string]map[string]api.
 		roomData[key.SessionID] = key.KeyBackupSession
 		result[key.RoomID] = roomData
 	}
-	return result, nil
+	return result, rows.Err()
 }

userapi/storage/postgres/key_changes_table.go

@@ -115,7 +115,7 @@ func (s *keyChangesStatements) SelectKeyChanges(
 	for rows.Next() {
 		var userID string
 		var offset int64
-		if err := rows.Scan(&userID, &offset); err != nil {
+		if err = rows.Scan(&userID, &offset); err != nil {
 			return nil, 0, err
 		}
 		if offset > latestOffset {
@@ -123,5 +123,6 @@ func (s *keyChangesStatements) SelectKeyChanges(
 		}
 		userIDs = append(userIDs, userID)
 	}
+	err = rows.Err()
 	return
 }

userapi/storage/postgres/one_time_keys_table.go

@@ -134,7 +134,7 @@ func (s *oneTimeKeysStatements) CountOneTimeKeys(ctx context.Context, userID, de
 		}
 		counts.KeyCount[algorithm] = count
 	}
-	return counts, nil
+	return counts, rows.Err()
 }
 
 func (s *oneTimeKeysStatements) InsertOneTimeKeys(ctx context.Context, txn *sql.Tx, keys api.OneTimeKeys) (*api.OneTimeKeysCount, error) {

userapi/storage/postgres/profile_table.go

@@ -165,5 +165,5 @@ func (s *profilesStatements) SelectProfilesBySearch(
 			profiles = append(profiles, profile)
 		}
 	}
-	return profiles, nil
+	return profiles, rows.Err()
 }

userapi/storage/postgres/threepid_table.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"database/sql"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
 	"github.com/matrix-org/gomatrixserverlib/spec"
@@ -94,6 +95,7 @@ func (s *threepidStatements) SelectThreePIDsForLocalpart(
 	if err != nil {
 		return
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectThreePIDsForLocalpart: failed to close rows")
 
 	threepids = []authtypes.ThreePID{}
 	for rows.Next() {
@@ -107,7 +109,7 @@ func (s *threepidStatements) SelectThreePIDsForLocalpart(
 			Medium:  medium,
 		})
 	}
-
+	err = rows.Err()
 	return
 }
 

userapi/storage/sqlite3/account_data_table.go

@@ -19,6 +19,7 @@ import (
 	"database/sql"
 	"encoding/json"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/userapi/storage/tables"
 	"github.com/matrix-org/gomatrixserverlib/spec"
@@ -95,6 +96,7 @@ func (s *accountDataStatements) SelectAccountData(
 	if err != nil {
 		return nil, nil, err
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectAccountData: failed to close rows")
 
 	global := map[string]json.RawMessage{}
 	rooms := map[string]map[string]json.RawMessage{}
@@ -118,7 +120,7 @@ func (s *accountDataStatements) SelectAccountData(
 		}
 	}
 
-	return global, rooms, nil
+	return global, rooms, rows.Err()
 }
 
 func (s *accountDataStatements) SelectAccountDataByType(

userapi/storage/sqlite3/cross_signing_keys_table.go

@@ -76,7 +76,7 @@ func (s *crossSigningKeysStatements) SelectCrossSigningKeysForUser(
 	for rows.Next() {
 		var keyTypeInt int16
 		var keyData spec.Base64Bytes
-		if err := rows.Scan(&keyTypeInt, &keyData); err != nil {
+		if err = rows.Scan(&keyTypeInt, &keyData); err != nil {
 			return nil, err
 		}
 		keyType, ok := types.KeyTypeIntToPurpose[keyTypeInt]
@@ -85,6 +85,7 @@ func (s *crossSigningKeysStatements) SelectCrossSigningKeysForUser(
 		}
 		r[keyType] = keyData
 	}
+	err = rows.Err()
 	return
 }
 

userapi/storage/sqlite3/cross_signing_sigs_table.go

@@ -96,7 +96,7 @@ func (s *crossSigningSigsStatements) SelectCrossSigningSigsForTarget(
 		var userID string
 		var keyID gomatrixserverlib.KeyID
 		var signature spec.Base64Bytes
-		if err := rows.Scan(&userID, &keyID, &signature); err != nil {
+		if err = rows.Scan(&userID, &keyID, &signature); err != nil {
 			return nil, err
 		}
 		if _, ok := r[userID]; !ok {
@@ -104,6 +104,7 @@ func (s *crossSigningSigsStatements) SelectCrossSigningSigsForTarget(
 		}
 		r[userID][keyID] = signature
 	}
+	err = rows.Err()
 	return
 }
 

userapi/storage/sqlite3/devices_table.go

@@ -296,6 +296,7 @@ func (s *devicesStatements) SelectDevicesByLocalpart(
 	if err != nil {
 		return devices, err
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectDevicesByLocalpart: failed to close rows")
 
 	var dev api.Device
 	var lastseents sql.NullInt64
@@ -325,7 +326,7 @@ func (s *devicesStatements) SelectDevicesByLocalpart(
 		devices = append(devices, dev)
 	}
 
-	return devices, nil
+	return devices, rows.Err()
 }
 
 func (s *devicesStatements) SelectDevicesByID(ctx context.Context, deviceIDs []string) ([]api.Device, error) {

userapi/storage/sqlite3/key_backup_table.go

@@ -162,5 +162,5 @@ func unpackKeys(ctx context.Context, rows *sql.Rows) (map[string]map[string]api.
 		roomData[key.SessionID] = key.KeyBackupSession
 		result[key.RoomID] = roomData
 	}
-	return result, nil
+	return result, rows.Err()
 }

userapi/storage/sqlite3/key_changes_table.go

@@ -113,7 +113,7 @@ func (s *keyChangesStatements) SelectKeyChanges(
 	for rows.Next() {
 		var userID string
 		var offset int64
-		if err := rows.Scan(&userID, &offset); err != nil {
+		if err = rows.Scan(&userID, &offset); err != nil {
 			return nil, 0, err
 		}
 		if offset > latestOffset {
@@ -121,5 +121,6 @@ func (s *keyChangesStatements) SelectKeyChanges(
 		}
 		userIDs = append(userIDs, userID)
 	}
+	err = rows.Err()
 	return
 }

userapi/storage/sqlite3/one_time_keys_table.go

@@ -140,7 +140,7 @@ func (s *oneTimeKeysStatements) CountOneTimeKeys(ctx context.Context, userID, de
 		}
 		counts.KeyCount[algorithm] = count
 	}
-	return counts, nil
+	return counts, rows.Err()
 }
 
 func (s *oneTimeKeysStatements) InsertOneTimeKeys(

userapi/storage/sqlite3/profile_table.go

@@ -173,5 +173,5 @@ func (s *profilesStatements) SelectProfilesBySearch(
 			profiles = append(profiles, profile)
 		}
 	}
-	return profiles, nil
+	return profiles, rows.Err()
 }

userapi/userapi.go

@@ -18,10 +18,12 @@ import (
 	"time"
 
 	fedsenderapi "github.com/matrix-org/dendrite/federationapi/api"
+	"github.com/matrix-org/dendrite/federationapi/statistics"
 	"github.com/matrix-org/dendrite/internal/pushgateway"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/setup/process"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/sirupsen/logrus"
 
 	rsapi "github.com/matrix-org/dendrite/roomserver/api"
@@ -47,6 +49,7 @@ func NewInternalAPI(
 	rsAPI rsapi.UserRoomserverAPI,
 	fedClient fedsenderapi.KeyserverFederationAPI,
 	enableMetrics bool,
+	blacklistedOrBackingOffFn func(s spec.ServerName) (*statistics.ServerStatistics, error),
 ) *internal.UserInternalAPI {
 	js, _ := natsInstance.Prepare(processContext, &dendriteCfg.Global.JetStream)
 	appServices := dendriteCfg.Derived.ApplicationServices
@@ -100,7 +103,7 @@ func NewInternalAPI(
 		FedClient:            fedClient,
 	}
 
-	updater := internal.NewDeviceListUpdater(processContext, keyDB, userAPI, keyChangeProducer, fedClient, dendriteCfg.UserAPI.WorkerCount, rsAPI, dendriteCfg.Global.ServerName, enableMetrics)
+	updater := internal.NewDeviceListUpdater(processContext, keyDB, userAPI, keyChangeProducer, fedClient, dendriteCfg.UserAPI.WorkerCount, rsAPI, dendriteCfg.Global.ServerName, enableMetrics, blacklistedOrBackingOffFn)
 	userAPI.Updater = updater
 	// Remove users which we don't share a room with anymore
 	if err := updater.CleanUp(); err != nil {