Use FillBuilder when possible

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

@@ -26,12 +26,14 @@ import (
 var ErrRoomNoExists = errors.New("Room does not exist")
 
 // FillBuilder fills the PrevEvents, AuthEvents and Depth fields of an event builder
-// using the roomserver query API client provided
+// using the roomserver query API client provided. Also fills roomserver query API
+// response (if provided) in case the function calling FillBuilder needs to use it.
 // Returns ErrRoomNoExists if the state of the room could not be retrieved because
 // the room doesn't exist
 // Returns an error if something else went wrong
 func FillBuilder(
 	builder *gomatrixserverlib.EventBuilder, queryAPI api.RoomserverQueryAPI,
+	queryRes *api.QueryLatestEventsAndStateResponse,
 ) error {
 	eventsNeeded, err := gomatrixserverlib.StateNeededForEventBuilder(builder)
 	if err != nil {
@@ -43,8 +45,10 @@ func FillBuilder(
 		RoomID:       builder.RoomID,
 		StateToFetch: eventsNeeded.Tuples(),
 	}
-	var queryRes api.QueryLatestEventsAndStateResponse
+	if queryRes == nil {
-	if queryErr := queryAPI.QueryLatestEventsAndState(&queryReq, &queryRes); queryErr != nil {
+		queryRes = &api.QueryLatestEventsAndStateResponse{}
+	}
+	if queryErr := queryAPI.QueryLatestEventsAndState(&queryReq, queryRes); queryErr != nil {
 		return err
 	}
 

src/github.com/matrix-org/dendrite/clientapi/readers/profile.go

@@ -284,36 +284,10 @@ func buildMembershipEvents(
 			return nil, err
 		}
 
-		eventsNeeded, err := gomatrixserverlib.StateNeededForEventBuilder(&builder)
+		if err := events.FillBuilder(&builder, queryAPI, nil); err != nil {
-		if err != nil {
 			return nil, err
 		}
 
-		// Ask the roomserver for information about this room
-		queryReq := api.QueryLatestEventsAndStateRequest{
-			RoomID:       membership.RoomID,
-			StateToFetch: eventsNeeded.Tuples(),
-		}
-		var queryRes api.QueryLatestEventsAndStateResponse
-		if queryErr := queryAPI.QueryLatestEventsAndState(&queryReq, &queryRes); queryErr != nil {
-			return nil, err
-		}
-
-		builder.Depth = queryRes.Depth
-		builder.PrevEvents = queryRes.LatestEvents
-
-		authEvents := gomatrixserverlib.NewAuthEvents(nil)
-
-		for i := range queryRes.StateEvents {
-			authEvents.AddEvent(&queryRes.StateEvents[i])
-		}
-
-		refs, err := eventsNeeded.AuthEventReferences(&authEvents)
-		if err != nil {
-			return nil, err
-		}
-		builder.AuthEvents = refs
-
 		eventID := fmt.Sprintf("$%s:%s", util.RandomString(16), cfg.Matrix.ServerName)
 		now := time.Now()
 		event, err := builder.Build(eventID, now, cfg.Matrix.ServerName, cfg.Matrix.KeyID, cfg.Matrix.PrivateKey)

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

@@ -77,7 +77,7 @@ func SendMembership(
 		return httputil.LogThenError(req, err)
 	}
 
-	if err = events.FillBuilder(&builder, queryAPI); err == events.ErrRoomNoExists {
+	if err = events.FillBuilder(&builder, queryAPI, nil); err == events.ErrRoomNoExists {
 		return util.JSONResponse{
 			Code: 404,
 			JSON: jsonerror.NotFound(err.Error()),

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

@@ -21,6 +21,7 @@ import (
 	"time"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
+	"github.com/matrix-org/dendrite/clientapi/events"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
 	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
@@ -64,36 +65,16 @@ func SendEvent(
 	}
 	builder.SetContent(r)
 
-	// work out what will be required in order to send this event
-	needed, err := gomatrixserverlib.StateNeededForEventBuilder(&builder)
-	if err != nil {
-		return httputil.LogThenError(req, err)
-	}
-
-	// Ask the roomserver for information about this room
-	queryReq := api.QueryLatestEventsAndStateRequest{
-		RoomID:       roomID,
-		StateToFetch: needed.Tuples(),
-	}
 	var queryRes api.QueryLatestEventsAndStateResponse
-	if queryErr := queryAPI.QueryLatestEventsAndState(&queryReq, &queryRes); queryErr != nil {
+	if err := events.FillBuilder(&builder, queryAPI, &queryRes); err == events.ErrRoomNoExists {
-		return httputil.LogThenError(req, queryErr)
-	}
-	if !queryRes.RoomExists {
 		return util.JSONResponse{
 			Code: 404,
 			JSON: jsonerror.NotFound("Room does not exist"),
 		}
+	} else if err != nil {
+		return httputil.LogThenError(req, err)
 	}
 
-	// set the fields we previously couldn't do and build the event
-	builder.PrevEvents = queryRes.LatestEvents // the current events will be the prev events of the new event
-	var refs []gomatrixserverlib.EventReference
-	for _, e := range queryRes.StateEvents {
-		refs = append(refs, e.EventReference())
-	}
-	builder.AuthEvents = refs
-	builder.Depth = queryRes.Depth
 	eventID := fmt.Sprintf("$%s:%s", util.RandomString(16), cfg.Matrix.ServerName)
 	e, err := builder.Build(
 		eventID, time.Now(), cfg.Matrix.ServerName, cfg.Matrix.KeyID, cfg.Matrix.PrivateKey,