use go module for dependencies (#594)

federationapi/routing/backfill.go

@@ -0,0 +1,102 @@
+// Copyright 2018 New Vector Ltd
+//
+// 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"
+	"strconv"
+
+	"github.com/matrix-org/dendrite/clientapi/httputil"
+	"github.com/matrix-org/dendrite/clientapi/jsonerror"
+	"github.com/matrix-org/dendrite/common/config"
+	"github.com/matrix-org/dendrite/federationapi/types"
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+)
+
+// Backfill implements the /backfill federation endpoint.
+// https://matrix.org/docs/spec/server_server/unstable.html#get-matrix-federation-v1-backfill-roomid
+func Backfill(
+	httpReq *http.Request,
+	request *gomatrixserverlib.FederationRequest,
+	query api.RoomserverQueryAPI,
+	roomID string,
+	cfg config.Dendrite,
+) util.JSONResponse {
+	var res api.QueryBackfillResponse
+	var eIDs []string
+	var limit string
+	var exists bool
+	var err error
+
+	// Check the room ID's format.
+	if _, _, err = gomatrixserverlib.SplitID('!', roomID); err != nil {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.MissingArgument("Bad room ID: " + err.Error()),
+		}
+	}
+
+	// Check if all of the required parameters are there.
+	eIDs, exists = httpReq.URL.Query()["v"]
+	if !exists {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.MissingArgument("v is missing"),
+		}
+	}
+	limit = httpReq.URL.Query().Get("limit")
+	if len(limit) == 0 {
+		return util.JSONResponse{
+			Code: http.StatusBadRequest,
+			JSON: jsonerror.MissingArgument("limit is missing"),
+		}
+	}
+
+	// Populate the request.
+	req := api.QueryBackfillRequest{
+		EarliestEventsIDs: eIDs,
+		ServerName:        request.Origin(),
+	}
+	if req.Limit, err = strconv.Atoi(limit); err != nil {
+		return httputil.LogThenError(httpReq, err)
+	}
+
+	// Query the roomserver.
+	if err = query.QueryBackfill(httpReq.Context(), &req, &res); err != nil {
+		return httputil.LogThenError(httpReq, err)
+	}
+
+	// Filter any event that's not from the requested room out.
+	evs := make([]gomatrixserverlib.Event, 0)
+
+	var ev gomatrixserverlib.Event
+	for _, ev = range res.Events {
+		if ev.RoomID() == roomID {
+			evs = append(evs, ev)
+		}
+	}
+
+	txn := types.NewTransaction()
+	txn.Origin = cfg.Matrix.ServerName
+	txn.PDUs = evs
+
+	// Send the events to the client.
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: txn,
+	}
+}