Support the since and limit parameters

src/github.com/matrix-org/dendrite/clientapi/routing/routing.go

@@ -278,7 +278,7 @@ func Setup(
 			// TODO: Return a list of public rooms
 			return writers.GetPublicRooms(req, publicRoomAPI)
 		}),
-	)
+	).Methods("GET", "POST", "OPTIONS")
 
 	unstableMux.Handle("/thirdparty/protocols",
 		common.MakeAPI("thirdparty_protocols", func(req *http.Request) util.JSONResponse {

src/github.com/matrix-org/dendrite/clientapi/writers/room_directory.go

@@ -16,6 +16,7 @@ package writers
 
 import (
 	"net/http"
+	"strconv"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
@@ -69,11 +70,14 @@ func SetVisibility(
 	}
 }
 
-// GetPublicRooms implements GET /publicRooms
+// GetPublicRooms implements GET and POST /publicRooms
 func GetPublicRooms(
 	req *http.Request, publicRoomAPI api.RoomserverPublicRoomAPI,
 ) util.JSONResponse {
 	queryReq := api.GetPublicRoomsRequest{}
+	if fillErr := fillPublicRoomsReq(req, &queryReq); fillErr != nil {
+		return *fillErr
+	}
 	var queryRes api.GetPublicRoomsResponse
 	if err := publicRoomAPI.GetPublicRooms(&queryReq, &queryRes); err != nil {
 		return httputil.LogThenError(req, err)
@@ -84,3 +88,23 @@ func GetPublicRooms(
 		JSON: queryRes,
 	}
 }
+
+func fillPublicRoomsReq(httpReq *http.Request, queryReq *api.GetPublicRoomsRequest) *util.JSONResponse {
+	if httpReq.Method == "GET" {
+		limit, err := strconv.Atoi(httpReq.FormValue("limit"))
+		// Atoi returns 0 and an error when trying to parse an empty string
+		// In that case, we want to assign 0 so we ignore the error
+		if err != nil && len(httpReq.FormValue("limit")) > 0 {
+			reqErr := httputil.LogThenError(httpReq, err)
+			return &reqErr
+		}
+		queryReq.Limit = int16(limit)
+		queryReq.Since = httpReq.FormValue("since")
+	} else if httpReq.Method == "POST" {
+		if reqErr := httputil.UnmarshalJSONRequest(httpReq, queryReq); reqErr != nil {
+			return reqErr
+		}
+	}
+
+	return nil
+}

src/github.com/matrix-org/dendrite/roomserver/api/public_room.go

@@ -42,9 +42,16 @@ type GetRoomVisibilityResponse struct {
 }
 
 // GetPublicRoomsRequest is a request to GetPublicRooms
+// TODO: Support the "server" request parameter
 type GetPublicRoomsRequest struct {
-	Limit int16  `json:"limit"`
-	Since string `json:"since"`
+	Limit  int16  `json:"limit"`
+	Since  string `json:"since"`
+	Filter Filter `json:"filter"`
+}
+
+// Filter implements the Filter structure from the Matrix spec
+type Filter struct {
+	SearchTerm string `json:"generic_search_term"`
 }
 
 // GetPublicRoomsResponse is a response to GetPublicRooms

src/github.com/matrix-org/dendrite/roomserver/publicroom/public_room.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"errors"
 	"net/http"
+	"strconv"
 
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -108,7 +109,18 @@ func (r *RoomserverPublicRoomAPI) GetPublicRooms(
 	req *api.GetPublicRoomsRequest,
 	response *api.GetPublicRoomsResponse,
 ) error {
-	// TODO: Limit by req.Limit and offset by req.Since
+	var limit int16
+	var offset int64
+
+	limit = req.Limit
+	ofst, err := strconv.Atoi(req.Since)
+	// Atoi returns 0 and an error when trying to parse an empty string
+	// In that case, we want to assign 0 so we ignore the error
+	if err != nil && len(req.Since) > 0 {
+		return err
+	}
+	offset = int64(ofst)
+
 	roomIDs, err := r.DB.GetPublicRoomIDs()
 	if err != nil {
 		return err
@@ -133,7 +145,13 @@ func (r *RoomserverPublicRoomAPI) GetPublicRooms(
 		chunks = append(chunks, chunk)
 	}
 
-	response.Chunks = chunks
+	if limit == 0 {
+		// If limit is 0, don't limit the results
+		response.Chunks = chunks[offset:]
+	} else {
+		response.Chunks = chunks[offset:limit]
+	}
+
 	return nil
 }