From dfa845efb433c799d01831968cd7d7207e87460b Mon Sep 17 00:00:00 2001
From: Helder Ferreira <me@helderferreira.io>
Date: Wed, 29 Dec 2021 12:19:16 +0000
Subject: [PATCH] Fix concurrency issues creating/getting the space

---
 main.go |  4 +++-
 user.go | 60 +++++++++++++++++++++++++++++++--------------------------
 2 files changed, 36 insertions(+), 28 deletions(-)

diff --git a/main.go b/main.go
index 2bd520d..e210ec6 100644
--- a/main.go
+++ b/main.go
@@ -180,8 +180,9 @@ type Bridge struct {
 	usersByUsername     map[string]*User
 	usersLock           sync.Mutex
 	spaceRooms          map[id.RoomID]*User
-	managementRoomsLock sync.Mutex
+	spaceRoomsLock      sync.Mutex
 	managementRooms     map[id.RoomID]*User
+	managementRoomsLock sync.Mutex
 	portalsByMXID       map[id.RoomID]*Portal
 	portalsByJID        map[database.PortalKey]*Portal
 	portalsLock         sync.Mutex
@@ -480,6 +481,7 @@ func main() {
 	(&Bridge{
 		usersByMXID:         make(map[id.UserID]*User),
 		usersByUsername:     make(map[string]*User),
+		spaceRooms:          make(map[id.RoomID]*User),
 		managementRooms:     make(map[id.RoomID]*User),
 		portalsByMXID:       make(map[id.RoomID]*Portal),
 		portalsByJID:        make(map[database.PortalKey]*Portal),
diff --git a/user.go b/user.go
index eae77cc..ec7da6f 100644
--- a/user.go
+++ b/user.go
@@ -57,8 +57,9 @@ type User struct {
 	Whitelisted      bool
 	RelayWhitelisted bool
 
-	mgmtCreateLock sync.Mutex
-	connLock       sync.Mutex
+	mgmtCreateLock  sync.Mutex
+	spaceCreateLock sync.Mutex
+	connLock        sync.Mutex
 
 	historySyncs     chan *events.HistorySync
 	prevBridgeStatus *BridgeState
@@ -182,45 +183,50 @@ func (bridge *Bridge) NewUser(dbUser *database.User) *User {
 func (user *User) getSpaceRoom() id.RoomID {
 	var roomID id.RoomID
 
-	user.log.Debugln("getSpaceRoom called")
-
 	if len(user.SpaceRoom) == 0 {
 		//TODO check if Spaces creation is enabled by config
-		creationContent := make(map[string]interface{})
-		creationContent["type"] = "m.space"
 
-		user.log.Debugln("Creating a new space for the user")
+		//Create Space
+		user.log.Debugln("Locking to create space.")
+		user.spaceCreateLock.Lock()
+		defer user.spaceCreateLock.Unlock()
 
-		user.log.Debugln("Inviting user " + user.MXID)
-		var invite []id.UserID
-		invite = append(invite, user.MXID)
-
-		resp, err := user.bridge.Bot.CreateRoom(&mautrix.ReqCreateRoom{
-			Visibility:      "private",
-			Name:            "WhatsApp",
-			Topic:           "WhatsApp bridge Space",
-			Invite:          invite,
-			CreationContent: creationContent,
-		})
-		if err != nil {
-			user.log.Errorln("Failed to auto-create space room:", err)
+		if len(user.SpaceRoom) != 0 {
+			roomID = user.SpaceRoom
+			user.log.Debugln("Returning space after lock" + user.SpaceRoom)
 		} else {
-			user.setSpaceRoom(resp.RoomID)
+			creationContent := make(map[string]interface{})
+			creationContent["type"] = "m.space"
+
+			user.log.Debugln("Creating a new space for the user")
+
+			user.log.Debugln("Inviting user " + user.MXID)
+			var invite []id.UserID
+			invite = append(invite, user.MXID)
+
+			resp, err := user.bridge.Bot.CreateRoom(&mautrix.ReqCreateRoom{
+				Visibility:      "private",
+				Name:            "WhatsApp",
+				Topic:           "WhatsApp bridge Space",
+				Invite:          invite,
+				CreationContent: creationContent,
+			})
+			if err != nil {
+				user.log.Errorln("Failed to auto-create space room:", err)
+			} else {
+				user.setSpaceRoom(resp.RoomID)
+				roomID = resp.RoomID
+			}
 		}
 	} else {
 		user.log.Debugln("Space found" + user.SpaceRoom)
 		roomID = user.SpaceRoom
 	}
+
 	return roomID
 }
 
 func (user *User) setSpaceRoom(spaceID id.RoomID) {
-	existingUser, ok := user.bridge.spaceRooms[spaceID]
-	if ok {
-		existingUser.SpaceRoom = ""
-		existingUser.Update()
-	}
-
 	user.SpaceRoom = spaceID
 	user.bridge.spaceRooms[user.SpaceRoom] = user
 	user.Update()