Added /upgrade endpoint (#2307)

* Added /upgrade endpoint

* fix

* Fix lints

* More lint lifex

* Move room upgrading to the roomserver

* Remove extraneous arg

* Fix HTTP API for `PerformUpgrade`

* Reduce number of API calls in `generateInitialEvents`, preserve membership fields

* Refactor `generateInitialEvents` to preserve old state events for all but the essential room setup events

* Handle ban events in the state transfer

* Refactor and comment `createTemporaryPowerLevels`

* Only send two power levels if we needed to override the levels, preserve miscellaneous fields in the create event

* Fix copyrights

* Review comments @S7evinK

* Update sytest whitelist

* Specify empty state keys, use `EventLevel`, remove unnecessary check on state copy

* Add comment to `restrictOldRoomPowerLevels`

* Ensure canonical aliases exist before clearing

* Copy invites as well as bans

* Fix return error on `m.room.tombstone` handling in client API

* Relax checks for well-formedness of join rules, membership event etc

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

clientapi/routing/routing.go

@@ -957,6 +957,16 @@ func Setup(
 		}),
 	).Methods(http.MethodPost, http.MethodOptions)
 
+	v3mux.Handle("/rooms/{roomID}/upgrade",
+		httputil.MakeAuthAPI("rooms_upgrade", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return UpgradeRoom(req, device, cfg, vars["roomID"], userAPI, rsAPI, asAPI)
+		}),
+	).Methods(http.MethodPost, http.MethodOptions)
+
 	v3mux.Handle("/devices",
 		httputil.MakeAuthAPI("get_devices", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return GetDevicesByLocalpart(req, userAPI, device)

clientapi/routing/sendevent.go

@@ -272,5 +272,24 @@ func generateSendEvent(
 			JSON: jsonerror.Forbidden(err.Error()), // TODO: Is this error string comprehensible to the client?
 		}
 	}
+
+	// User should not be able to send a tombstone event to the same room.
+	if e.Type() == "m.room.tombstone" {
+		content := make(map[string]interface{})
+		if err = json.Unmarshal(e.Content(), &content); err != nil {
+			util.GetLogger(ctx).WithError(err).Error("Cannot unmarshal the event content.")
+			return nil, &util.JSONResponse{
+				Code: http.StatusBadRequest,
+				JSON: jsonerror.BadJSON("Cannot unmarshal the event content."),
+			}
+		}
+		if content["replacement_room"] == e.RoomID() {
+			return nil, &util.JSONResponse{
+				Code: http.StatusBadRequest,
+				JSON: jsonerror.InvalidParam("Cannot send tombstone event that points to the same room."),
+			}
+		}
+	}
+
 	return e.Event, nil
 }

clientapi/routing/upgrade_room.go

@@ -0,0 +1,92 @@
+// Copyright 2022 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package routing
+
+import (
+	"net/http"
+
+	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
+	"github.com/matrix-org/dendrite/clientapi/httputil"
+	"github.com/matrix-org/dendrite/clientapi/jsonerror"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/dendrite/roomserver/version"
+	"github.com/matrix-org/dendrite/setup/config"
+	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+)
+
+type upgradeRoomRequest struct {
+	NewVersion string `json:"new_version"`
+}
+
+type upgradeRoomResponse struct {
+	ReplacementRoom string `json:"replacement_room"`
+}
+
+// UpgradeRoom implements /upgrade
+func UpgradeRoom(
+	req *http.Request, device *userapi.Device,
+	cfg *config.ClientAPI,
+	roomID string, profileAPI userapi.UserProfileAPI,
+	rsAPI roomserverAPI.RoomserverInternalAPI,
+	asAPI appserviceAPI.AppServiceQueryAPI,
+) util.JSONResponse {
+	var r upgradeRoomRequest
+	if rErr := httputil.UnmarshalJSONRequest(req, &r); rErr != nil {
+		return *rErr
+	}
+
+	// Validate that the room version is supported
+	if _, err := version.SupportedRoomVersion(gomatrixserverlib.RoomVersion(r.NewVersion)); err != nil {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.UnsupportedRoomVersion("This server does not support that room version"),
+		}
+	}
+
+	upgradeReq := roomserverAPI.PerformRoomUpgradeRequest{
+		UserID:      device.UserID,
+		RoomID:      roomID,
+		RoomVersion: gomatrixserverlib.RoomVersion(r.NewVersion),
+	}
+	upgradeResp := roomserverAPI.PerformRoomUpgradeResponse{}
+
+	rsAPI.PerformRoomUpgrade(req.Context(), &upgradeReq, &upgradeResp)
+
+	if upgradeResp.Error != nil {
+		if upgradeResp.Error.Code == roomserverAPI.PerformErrorNoRoom {
+			return util.JSONResponse{
+				Code: http.StatusNotFound,
+				JSON: jsonerror.NotFound("Room does not exist"),
+			}
+		} else if upgradeResp.Error.Code == roomserverAPI.PerformErrorNotAllowed {
+			return util.JSONResponse{
+				Code: http.StatusForbidden,
+				JSON: jsonerror.Forbidden(upgradeResp.Error.Msg),
+			}
+		} else {
+			return jsonerror.InternalServerError()
+		}
+
+	}
+
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: upgradeRoomResponse{
+			ReplacementRoom: upgradeResp.NewRoomID,
+		},
+	}
+}