Add tests around federationapi's txnReq (#1010)

* Add necessary stubs for testing txnReq

* Add basic tests

federationapi/routing/send.go

@@ -103,8 +103,17 @@ type txnReq struct {
 	rsAPI       api.RoomserverInternalAPI
 	producer    *producers.RoomserverProducer
 	eduProducer *producers.EDUServerProducer
-	keys        gomatrixserverlib.KeyRing
+	keys        gomatrixserverlib.JSONVerifier
-	federation  *gomatrixserverlib.FederationClient
+	federation  txnFederationClient
+}
+
+// A subset of FederationClient functionality that txn requires. Useful for testing.
+type txnFederationClient interface {
+	LookupState(ctx context.Context, s gomatrixserverlib.ServerName, roomID string, eventID string, roomVersion gomatrixserverlib.RoomVersion) (
+		res gomatrixserverlib.RespState, err error,
+	)
+	LookupStateIDs(ctx context.Context, s gomatrixserverlib.ServerName, roomID string, eventID string) (res gomatrixserverlib.RespStateIDs, err error)
+	GetEvent(ctx context.Context, s gomatrixserverlib.ServerName, eventID string) (res gomatrixserverlib.Transaction, err error)
 }
 
 func (t *txnReq) processTransaction() (*gomatrixserverlib.RespSend, error) {

federationapi/routing/send_test.go

@@ -0,0 +1,399 @@
+package routing
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/matrix-org/dendrite/clientapi/producers"
+	eduAPI "github.com/matrix-org/dendrite/eduserver/api"
+	fsAPI "github.com/matrix-org/dendrite/federationsender/api"
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/gomatrixserverlib"
+)
+
+const (
+	testOrigin      = gomatrixserverlib.ServerName("kaer.morhen")
+	testDestination = gomatrixserverlib.ServerName("white.orchard")
+)
+
+var (
+	testRoomVersion = gomatrixserverlib.RoomVersionV1
+	testData        = []json.RawMessage{
+		[]byte(`{"auth_events":[],"content":{"creator":"@userid:kaer.morhen"},"depth":0,"event_id":"$0ok8ynDp7kjc95e3:kaer.morhen","hashes":{"sha256":"17kPoH+h0Dk4Omn7Sus0qMb6+oGcf+CZFEgDhv7UKWs"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[],"prev_state":[],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"jP4a04f5/F10Pw95FPpdCyKAO44JOwUQ/MZOOeA/RTU1Dn+AHPMzGSaZnuGjRr/xQuADt+I3ctb5ZQfLKNzHDw"}},"state_key":"","type":"m.room.create"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}]],"content":{"membership":"join"},"depth":1,"event_id":"$LEwEu0kxrtu5fOiS:kaer.morhen","hashes":{"sha256":"B7M88PhXf3vd1LaFtjQutFu4x/w7fHD28XKZ4sAsJTo"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}]],"prev_state":[],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"p2vqmuJn7ZBRImctSaKbXCAxCcBlIjPH9JHte1ouIUGy84gpu4eLipOvSBCLL26hXfC0Zrm4WUto6Hr+ohdrCg"}},"state_key":"@userid:kaer.morhen","type":"m.room.member"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"join_rule":"public"},"depth":2,"event_id":"$SMHlqUrNhhBBRLeN:kaer.morhen","hashes":{"sha256":"vIuJQvmMjrGxshAkj1SXe0C4RqvMbv4ZADDw9pFCWqQ"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"prev_state":[],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"hBMsb3Qppo3RaqqAl4JyTgaiWEbW5hlckATky6PrHun+F3YM203TzG7w9clwuQU5F5pZoB1a6nw+to0hN90FAw"}},"state_key":"","type":"m.room.join_rules"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"history_visibility":"shared"},"depth":3,"event_id":"$6F1yGIbO0J7TM93h:kaer.morhen","hashes":{"sha256":"Mr23GKSlZW7UCCYLgOWawI2Sg6KIoMjUWO2TDenuOgw"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$SMHlqUrNhhBBRLeN:kaer.morhen",{"sha256":"SylzE8U02I+6eyEHgL+FlU0L5YdqrVp8OOlxKS9VQW0"}]],"prev_state":[],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"sHLKrFI3hKGrEJfpMVZSDS3LvLasQsy50CTsOwru9XTVxgRsPo6wozNtRVjxo1J3Rk18RC9JppovmQ5VR5EcDw"}},"state_key":"","type":"m.room.history_visibility"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"ban":50,"events":null,"events_default":0,"invite":0,"kick":50,"redact":50,"state_default":50,"users":null,"users_default":0},"depth":4,"event_id":"$UKNe10XzYzG0TeA9:kaer.morhen","hashes":{"sha256":"ngbP3yja9U5dlckKerUs/fSOhtKxZMCVvsfhPURSS28"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$6F1yGIbO0J7TM93h:kaer.morhen",{"sha256":"A4CucrKSoWX4IaJXhq02mBg1sxIyZEftbC+5p3fZAvk"}]],"prev_state":[],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"zOmwlP01QL3yFchzuR9WHvogOoBZA3oVtNIF3lM0ZfDnqlSYZB9sns27G/4HVq0k7alaK7ZE3oGoCrVnMkPNCw"}},"state_key":"","type":"m.room.power_levels"}`),
+		// messages
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"body":"Test Message"},"depth":5,"event_id":"$gl2T9l3qm0kUbiIJ:kaer.morhen","hashes":{"sha256":"Qx3nRMHLDPSL5hBAzuX84FiSSP0K0Kju2iFoBWH4Za8"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$UKNe10XzYzG0TeA9:kaer.morhen",{"sha256":"KtSRyMjt0ZSjsv2koixTRCxIRCGoOp6QrKscsW97XRo"}]],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"sqDgv3EG7ml5VREzmT9aZeBpS4gAPNIaIeJOwqjDhY0GPU/BcpX5wY4R7hYLrNe5cChgV+eFy/GWm1Zfg5FfDg"}},"type":"m.room.message"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"body":"Test Message"},"depth":6,"event_id":"$MYSbs8m4rEbsCWXD:kaer.morhen","hashes":{"sha256":"kgbYM7v4Ud2YaBsjBTolM4ySg6rHcJNYI6nWhMSdFUA"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$gl2T9l3qm0kUbiIJ:kaer.morhen",{"sha256":"C/rD04h9wGxRdN2G/IBfrgoE1UovzLZ+uskwaKZ37/Q"}]],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"x0UoKh968jj/F5l1/R7Ew0T6CTKuew3PLNHASNxqck/bkNe8yYQiDHXRr+kZxObeqPZZTpaF1+EI+bLU9W8GDQ"}},"type":"m.room.message"}`),
+		[]byte(`{"auth_events":[["$0ok8ynDp7kjc95e3:kaer.morhen",{"sha256":"sWCi6Ckp9rDimQON+MrUlNRkyfZ2tjbPbWfg2NMB18Q"}],["$LEwEu0kxrtu5fOiS:kaer.morhen",{"sha256":"1aKajq6DWHru1R1HJjvdWMEavkJJHGaTmPvfuERUXaA"}]],"content":{"body":"Test Message"},"depth":7,"event_id":"$N5x9WJkl9ClPrAEg:kaer.morhen","hashes":{"sha256":"FWM8oz4yquTunRZ67qlW2gzPDzdWfBP6RPHXhK1I/x8"},"origin":"kaer.morhen","origin_server_ts":0,"prev_events":[["$MYSbs8m4rEbsCWXD:kaer.morhen",{"sha256":"fatqgW+SE8mb2wFn3UN+drmluoD4UJ/EcSrL6Ur9q1M"}]],"room_id":"!roomid:kaer.morhen","sender":"@userid:kaer.morhen","signatures":{"kaer.morhen":{"ed25519:auto":"Y+LX/xcyufoXMOIoqQBNOzy6lZfUGB1ffgXIrSugk6obMiyAsiRejHQN/pciZXsHKxMJLYRFAz4zSJoS/LGPAA"}},"type":"m.room.message"}`),
+	}
+	testEvents      = []gomatrixserverlib.HeaderedEvent{}
+	testStateEvents = make(map[gomatrixserverlib.StateKeyTuple]gomatrixserverlib.HeaderedEvent)
+)
+
+func init() {
+	for _, j := range testData {
+		e, err := gomatrixserverlib.NewEventFromTrustedJSON(j, false, testRoomVersion)
+		if err != nil {
+			panic("cannot load test data: " + err.Error())
+		}
+		h := e.Headered(testRoomVersion)
+		testEvents = append(testEvents, h)
+		if e.StateKey() != nil {
+			testStateEvents[gomatrixserverlib.StateKeyTuple{
+				EventType: e.Type(),
+				StateKey:  *e.StateKey(),
+			}] = h
+		}
+	}
+}
+
+type testNopJSONVerifier struct {
+	// this verifier verifies nothing
+}
+
+func (t *testNopJSONVerifier) VerifyJSONs(ctx context.Context, requests []gomatrixserverlib.VerifyJSONRequest) ([]gomatrixserverlib.VerifyJSONResult, error) {
+	result := make([]gomatrixserverlib.VerifyJSONResult, len(requests))
+	return result, nil
+}
+
+type testEDUProducer struct {
+	// this producer keeps track of calls to InputTypingEvent
+	invocations []eduAPI.InputTypingEventRequest
+}
+
+func (p *testEDUProducer) InputTypingEvent(
+	ctx context.Context,
+	request *eduAPI.InputTypingEventRequest,
+	response *eduAPI.InputTypingEventResponse,
+) error {
+	p.invocations = append(p.invocations, *request)
+	return nil
+}
+
+type testRoomserverAPI struct {
+	inputRoomEvents       []api.InputRoomEvent
+	queryStateAfterEvents func(*api.QueryStateAfterEventsRequest) api.QueryStateAfterEventsResponse
+}
+
+func (t *testRoomserverAPI) SetFederationSenderAPI(fsAPI fsAPI.FederationSenderInternalAPI) {}
+
+func (t *testRoomserverAPI) InputRoomEvents(
+	ctx context.Context,
+	request *api.InputRoomEventsRequest,
+	response *api.InputRoomEventsResponse,
+) error {
+	t.inputRoomEvents = append(t.inputRoomEvents, request.InputRoomEvents...)
+	return nil
+}
+
+func (t *testRoomserverAPI) PerformJoin(
+	ctx context.Context,
+	req *api.PerformJoinRequest,
+	res *api.PerformJoinResponse,
+) error {
+	return nil
+}
+
+func (t *testRoomserverAPI) PerformLeave(
+	ctx context.Context,
+	req *api.PerformLeaveRequest,
+	res *api.PerformLeaveResponse,
+) error {
+	return nil
+}
+
+// Query the latest events and state for a room from the room server.
+func (t *testRoomserverAPI) QueryLatestEventsAndState(
+	ctx context.Context,
+	request *api.QueryLatestEventsAndStateRequest,
+	response *api.QueryLatestEventsAndStateResponse,
+) error {
+	return nil
+}
+
+// Query the state after a list of events in a room from the room server.
+func (t *testRoomserverAPI) QueryStateAfterEvents(
+	ctx context.Context,
+	request *api.QueryStateAfterEventsRequest,
+	response *api.QueryStateAfterEventsResponse,
+) error {
+	response.RoomVersion = testRoomVersion
+	response.QueryStateAfterEventsRequest = *request
+	res := t.queryStateAfterEvents(request)
+	response.PrevEventsExist = res.PrevEventsExist
+	response.RoomExists = res.RoomExists
+	response.StateEvents = res.StateEvents
+	return nil
+}
+
+// Query a list of events by event ID.
+func (t *testRoomserverAPI) QueryEventsByID(
+	ctx context.Context,
+	request *api.QueryEventsByIDRequest,
+	response *api.QueryEventsByIDResponse,
+) error {
+	return nil
+}
+
+// Query the membership event for an user for a room.
+func (t *testRoomserverAPI) QueryMembershipForUser(
+	ctx context.Context,
+	request *api.QueryMembershipForUserRequest,
+	response *api.QueryMembershipForUserResponse,
+) error {
+	return nil
+}
+
+// Query a list of membership events for a room
+func (t *testRoomserverAPI) QueryMembershipsForRoom(
+	ctx context.Context,
+	request *api.QueryMembershipsForRoomRequest,
+	response *api.QueryMembershipsForRoomResponse,
+) error {
+	return nil
+}
+
+// Query a list of invite event senders for a user in a room.
+func (t *testRoomserverAPI) QueryInvitesForUser(
+	ctx context.Context,
+	request *api.QueryInvitesForUserRequest,
+	response *api.QueryInvitesForUserResponse,
+) error {
+	return nil
+}
+
+// Query whether a server is allowed to see an event
+func (t *testRoomserverAPI) QueryServerAllowedToSeeEvent(
+	ctx context.Context,
+	request *api.QueryServerAllowedToSeeEventRequest,
+	response *api.QueryServerAllowedToSeeEventResponse,
+) error {
+	return nil
+}
+
+// Query missing events for a room from roomserver
+func (t *testRoomserverAPI) QueryMissingEvents(
+	ctx context.Context,
+	request *api.QueryMissingEventsRequest,
+	response *api.QueryMissingEventsResponse,
+) error {
+	return nil
+}
+
+// Query to get state and auth chain for a (potentially hypothetical) event.
+// Takes lists of PrevEventIDs and AuthEventsIDs and uses them to calculate
+// the state and auth chain to return.
+func (t *testRoomserverAPI) QueryStateAndAuthChain(
+	ctx context.Context,
+	request *api.QueryStateAndAuthChainRequest,
+	response *api.QueryStateAndAuthChainResponse,
+) error {
+	return nil
+}
+
+// Query a given amount (or less) of events prior to a given set of events.
+func (t *testRoomserverAPI) QueryBackfill(
+	ctx context.Context,
+	request *api.QueryBackfillRequest,
+	response *api.QueryBackfillResponse,
+) error {
+	return nil
+}
+
+// Asks for the default room version as preferred by the server.
+func (t *testRoomserverAPI) QueryRoomVersionCapabilities(
+	ctx context.Context,
+	request *api.QueryRoomVersionCapabilitiesRequest,
+	response *api.QueryRoomVersionCapabilitiesResponse,
+) error {
+	return nil
+}
+
+// Asks for the room version for a given room.
+func (t *testRoomserverAPI) QueryRoomVersionForRoom(
+	ctx context.Context,
+	request *api.QueryRoomVersionForRoomRequest,
+	response *api.QueryRoomVersionForRoomResponse,
+) error {
+	response.RoomVersion = testRoomVersion
+	return nil
+}
+
+// Set a room alias
+func (t *testRoomserverAPI) SetRoomAlias(
+	ctx context.Context,
+	req *api.SetRoomAliasRequest,
+	response *api.SetRoomAliasResponse,
+) error {
+	return nil
+}
+
+// Get the room ID for an alias
+func (t *testRoomserverAPI) GetRoomIDForAlias(
+	ctx context.Context,
+	req *api.GetRoomIDForAliasRequest,
+	response *api.GetRoomIDForAliasResponse,
+) error {
+	return nil
+}
+
+// Get all known aliases for a room ID
+func (t *testRoomserverAPI) GetAliasesForRoomID(
+	ctx context.Context,
+	req *api.GetAliasesForRoomIDRequest,
+	response *api.GetAliasesForRoomIDResponse,
+) error {
+	return nil
+}
+
+// Get the user ID of the creator of an alias
+func (t *testRoomserverAPI) GetCreatorIDForAlias(
+	ctx context.Context,
+	req *api.GetCreatorIDForAliasRequest,
+	response *api.GetCreatorIDForAliasResponse,
+) error {
+	return nil
+}
+
+// Remove a room alias
+func (t *testRoomserverAPI) RemoveRoomAlias(
+	ctx context.Context,
+	req *api.RemoveRoomAliasRequest,
+	response *api.RemoveRoomAliasResponse,
+) error {
+	return nil
+}
+
+type txnFedClient struct{}
+
+func (c *txnFedClient) LookupState(ctx context.Context, s gomatrixserverlib.ServerName, roomID string, eventID string, roomVersion gomatrixserverlib.RoomVersion) (
+	res gomatrixserverlib.RespState, err error,
+) {
+	return
+}
+func (c *txnFedClient) LookupStateIDs(ctx context.Context, s gomatrixserverlib.ServerName, roomID string, eventID string) (res gomatrixserverlib.RespStateIDs, err error) {
+	return
+}
+func (c *txnFedClient) GetEvent(ctx context.Context, s gomatrixserverlib.ServerName, eventID string) (res gomatrixserverlib.Transaction, err error) {
+	return
+}
+
+func mustCreateTransaction(rsAPI api.RoomserverInternalAPI, fedClient txnFederationClient, pdus []json.RawMessage, edus []gomatrixserverlib.EDU) *txnReq {
+	t := &txnReq{
+		context:     context.Background(),
+		rsAPI:       rsAPI,
+		producer:    producers.NewRoomserverProducer(rsAPI),
+		eduProducer: producers.NewEDUServerProducer(&testEDUProducer{}),
+		keys:        &testNopJSONVerifier{},
+		federation:  fedClient,
+	}
+	t.PDUs = pdus
+	t.EDUs = edus
+	t.Origin = testOrigin
+	t.TransactionID = gomatrixserverlib.TransactionID(fmt.Sprintf("%d", time.Now().UnixNano()))
+	t.Destination = testDestination
+	return t
+}
+
+func mustProcessTransaction(t *testing.T, txn *txnReq, pdusWithErrors []string) {
+	res, err := txn.processTransaction()
+	if err != nil {
+		t.Errorf("txn.processTransaction returned an error: %s", err)
+		return
+	}
+	if len(res.PDUs) != len(txn.PDUs) {
+		t.Errorf("txn.processTransaction did not return results for all PDUs, got %d want %d", len(res.PDUs), len(txn.PDUs))
+		return
+	}
+NextPDU:
+	for eventID, result := range res.PDUs {
+		if result.Error == "" {
+			continue
+		}
+		for _, eventIDWantError := range pdusWithErrors {
+			if eventID == eventIDWantError {
+				break NextPDU
+			}
+		}
+		t.Errorf("txn.processTransaction PDU %s returned an error %s", eventID, result.Error)
+	}
+}
+
+func fromStateTuples(tuples []gomatrixserverlib.StateKeyTuple, omitTuples []gomatrixserverlib.StateKeyTuple) (result []gomatrixserverlib.HeaderedEvent) {
+NextTuple:
+	for _, t := range tuples {
+		for _, o := range omitTuples {
+			if t == o {
+				break NextTuple
+			}
+		}
+		h, ok := testStateEvents[t]
+		if ok {
+			result = append(result, h)
+		}
+	}
+	return
+}
+
+func assertInputRoomEvents(t *testing.T, got []api.InputRoomEvent, want []gomatrixserverlib.HeaderedEvent) {
+	if len(got) != len(want) {
+		t.Errorf("wrong number of InputRoomEvents: got %d want %d", len(got), len(want))
+		return
+	}
+	for i := range got {
+		if got[i].Event.EventID() != want[i].EventID() {
+			t.Errorf("InputRoomEvents[%d] got %s want %s", i, got[i].Event.EventID(), want[i].EventID())
+		}
+	}
+}
+
+// The purpose of this test is to check that receiving an event over federation for which we have the prev_events works correctly, and passes it on
+// to the roomserver. It's the most basic test possible.
+func TestBasicTransaction(t *testing.T) {
+	rsAPI := &testRoomserverAPI{
+		queryStateAfterEvents: func(req *api.QueryStateAfterEventsRequest) api.QueryStateAfterEventsResponse {
+			return api.QueryStateAfterEventsResponse{
+				PrevEventsExist: true,
+				RoomExists:      true,
+				StateEvents:     fromStateTuples(req.StateToFetch, nil),
+			}
+		},
+	}
+	pdus := []json.RawMessage{
+		testData[len(testData)-1], // a message event
+	}
+	txn := mustCreateTransaction(rsAPI, &txnFedClient{}, pdus, nil)
+	mustProcessTransaction(t, txn, nil)
+	assertInputRoomEvents(t, rsAPI.inputRoomEvents, []gomatrixserverlib.HeaderedEvent{testEvents[len(testEvents)-1]})
+}
+
+// The purpose of this test is to check that if the event received fails auth checks the transaction is failed.
+func TestTransactionFailAuthChecks(t *testing.T) {
+	rsAPI := &testRoomserverAPI{
+		queryStateAfterEvents: func(req *api.QueryStateAfterEventsRequest) api.QueryStateAfterEventsResponse {
+			return api.QueryStateAfterEventsResponse{
+				PrevEventsExist: true,
+				RoomExists:      true,
+				// omit the create event so auth checks fail
+				StateEvents: fromStateTuples(req.StateToFetch, []gomatrixserverlib.StateKeyTuple{
+					{EventType: gomatrixserverlib.MRoomCreate, StateKey: ""},
+				}),
+			}
+		},
+	}
+	pdus := []json.RawMessage{
+		testData[len(testData)-1], // a message event
+	}
+	txn := mustCreateTransaction(rsAPI, &txnFedClient{}, pdus, nil)
+	mustProcessTransaction(t, txn, []string{
+		// expect the event to have an error
+		testEvents[len(testEvents)-1].EventID(),
+	})
+	assertInputRoomEvents(t, rsAPI.inputRoomEvents, nil) // expect no messages to be sent to the roomserver
+}