Add config key for default room version (#3171)

This PR adds a config key `room_server.default_config_key` to set the
default room version for the room server.

Signed-off-by: `Sam Wedgwood <sam@wedgwood.dev>`

1 files changed, 16 insertions, 0 deletions

diff --git a/setup/config/config_roomserver.go b/setup/config/config_roomserver.go
index 319c2419..06e7757f 100644
--- a/setup/config/config_roomserver.go
+++ b/setup/config/config_roomserver.go
@@ -1,12 +1,22 @@
 package config
 
+import (
+	"fmt"
+
+	"github.com/matrix-org/gomatrixserverlib"
+	log "github.com/sirupsen/logrus"
+)
+
 type RoomServer struct {
 	Matrix *Global `yaml:"-"`
 
+	DefaultRoomVersion gomatrixserverlib.RoomVersion `yaml:"default_room_version,omitempty"`
+
 	Database DatabaseOptions `yaml:"database,omitempty"`
 }
 
 func (c *RoomServer) Defaults(opts DefaultOpts) {
+	c.DefaultRoomVersion = gomatrixserverlib.RoomVersionV10
 	if opts.Generate {
 		if !opts.SingleDatabase {
 			c.Database.ConnectionString = "file:roomserver.db"
@@ -18,4 +28,10 @@ func (c *RoomServer) Verify(configErrs *ConfigErrors) {
 	if c.Matrix.DatabaseOptions.ConnectionString == "" {
 		checkNotEmpty(configErrs, "room_server.database.connection_string", string(c.Database.ConnectionString))
 	}
+
+	if !gomatrixserverlib.KnownRoomVersion(c.DefaultRoomVersion) {
+		configErrs.Add(fmt.Sprintf("invalid value for config key 'room_server.default_room_version': unsupported room version: %q", c.DefaultRoomVersion))
+	} else if !gomatrixserverlib.StableRoomVersion(c.DefaultRoomVersion) {
+		log.Warnf("WARNING: Provided default room version %q is unstable", c.DefaultRoomVersion)
+	}
 }